WO2022142898A1 - Direct current converter, electronic device, and control method for direct current converter - Google Patents

Direct current converter, electronic device, and control method for direct current converter Download PDF

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Publication number
WO2022142898A1
WO2022142898A1 PCT/CN2021/133101 CN2021133101W WO2022142898A1 WO 2022142898 A1 WO2022142898 A1 WO 2022142898A1 CN 2021133101 W CN2021133101 W CN 2021133101W WO 2022142898 A1 WO2022142898 A1 WO 2022142898A1
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Prior art keywords
voltage
circuit
output
input
converter
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PCT/CN2021/133101
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French (fr)
Chinese (zh)
Inventor
朱勇发
丁涛
曾智强
陈晓威
张敬阳
王平华
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华为技术有限公司
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Publication of WO2022142898A1 publication Critical patent/WO2022142898A1/en

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
    • H02M3/33576—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/33507—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of the output voltage or current, e.g. flyback converters
    • H02M3/33523—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of the output voltage or current, e.g. flyback converters with galvanic isolation between input and output of both the power stage and the feedback loop
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/5387—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/5387—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
    • H02M7/53871—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current

Definitions

  • the present application relates to the field of circuit technology, and in particular, to a DC converter, an electronic device and a control method of the DC converter.
  • the LLC resonant conversion circuit is a common DC-DC voltage conversion circuit, which can realize the soft switching of switch tubes and is used in voltage converters in various types of power systems.
  • voltage converters in power systems such as power management systems for electric/hybrid vehicles, photovoltaic power generation systems, communication power supply systems, and data centers often need to use LLC resonant conversion circuits to achieve voltage conversion.
  • the LLC resonant conversion circuit mainly includes: an inverter circuit, a resonant circuit, a transformer and a rectifier circuit.
  • the inverter circuit is used to convert the DC voltage received at the input end into AC power and output it to the resonant circuit.
  • the resonant circuit is used for To realize the soft switching of the inverter circuit, the transformer is used to output the alternating current output by the resonant circuit to the rectifier circuit, and the rectifier circuit is used to convert the alternating current output by the transformer into direct current and output it.
  • the input voltage of the voltage converter can fluctuate within a certain range, and the voltage conversion ratio of the voltage converter can be adjusted according to the load voltage regulation requirements.
  • LLC resonant conversion circuit In order to realize the soft switching sum of the switches in the inverter circuit to improve the conversion efficiency, the turn-on sequence of the switches of the inverter circuit is fixed, and the switching frequency of the switches is consistent with the resonant frequency of the resonant circuit. Therefore, the LLC resonance The voltage conversion ratio of the voltage conversion circuit of the conversion circuit is fixed, which makes it difficult for the LLC resonant conversion circuit to meet the voltage conversion requirements of the voltage converter.
  • the LLC resonant conversion circuit converts and outputs the voltage received at the input end of the voltage converter, and then regulates the DC voltage output by the LLC resonant conversion circuit through the voltage regulator circuit to output a voltage that meets the requirements of the voltage converter .
  • the overall efficiency of the two-stage series-connected architecture is equal to the multiplication of the two-stage efficiency. Since the conversion efficiency of the voltage regulator circuit is low, the conversion efficiency of the DC converter will be directly reduced.
  • a two-stage converter architecture with quasi-parallel conversion is proposed. As shown in Figure 2, the input terminal of the LLC resonant conversion circuit receives most of the input voltage and converts the received voltage into the voltage converter demand. The input terminal of the voltage regulation circuit receives a small part of the input voltage and converts the received voltage into the voltage required by the voltage converter.
  • the total efficiency of the voltage converter is the weighted average of the conversion efficiency of the two circuits and the ratio of the input voltage.
  • the voltage conversion ratio is fixed, which can only be achieved by increasing the voltage received at the input end of the voltage regulator circuit, which directly reduces the conversion efficiency of the voltage converter.
  • the present application provides a DC converter, an electronic device and a control method of the DC converter, which are used to improve the conversion efficiency of the DC converter.
  • the present application provides a control method for a DC converter, and the control method is applied to a DC converter.
  • the DC converter includes an LLC resonant conversion unit and a first voltage regulating circuit, the LLC resonant conversion unit has multiple voltage conversion gears, and the LLC resonant conversion unit includes a first input end, a second input end, a first output end and a first Two output terminals, the first voltage regulating circuit includes a third input terminal, a fourth input terminal, a third output terminal and a fourth output terminal, and the second input terminal is connected to the third input terminal.
  • the first output terminal is connected to the third output terminal, and the second output terminal is connected to the fourth output terminal.
  • the control method mainly includes the following steps:
  • the target transformation ratio is the transformation ratio between the input voltage of the DC converter and the output voltage of the DC converter;
  • the first transformation ratio of the LLC resonance conversion unit is determined in the voltage conversion gear;
  • the second transformation ratio of the first voltage regulating circuit is determined according to the target transformation ratio and the first transformation ratio.
  • the LLC resonant conversion unit and the input terminal of the first voltage regulating circuit are connected in series, and the output terminal is connected in parallel, and the two conversion devices respectively convert a part of the input voltage. Since the conversion efficiency of the LLC resonant conversion unit is greater than that of the first voltage regulating circuit , when the target conversion ratio of the DC converter and the minimum transformation ratio of the first voltage regulator circuit are determined, the first transformation ratio of the LLC resonant conversion circuit can be increased as much as possible. Since the input voltage of the LLC resonant conversion circuit is fixed, the first The larger the transformation ratio, the more the input voltage of the LLC can be received and the more power can be transmitted, which ensures the conversion efficiency of the entire DC converter.
  • the LLC when the first transformation ratio of the LLC resonant conversion unit is determined according to the target transformation ratio and the minimum transformation ratio of the voltage regulation circuit, the LLC is determined according to the minimum transformation ratio of the target transformation ratio and the first voltage regulation voltage.
  • the value range of the voltage conversion gear of the resonance conversion circuit; the largest voltage conversion gear within the value range of the voltage conversion gear of the LLC resonant conversion circuit is determined as the first transformation ratio.
  • the efficiency of the LLC resonant conversion unit is high, the efficiency of the switching power supply is further improved, and the maximum conversion ratio that can be achieved by the LLC resonant conversion unit can be found according to the minimum conversion ratio of the voltage regulator circuit, and the maximum conversion ratio can be used as The first transformation ratio of LLC resonant conversion enables the LLC resonant conversion unit to transmit more power.
  • using the target transformation ratio and the first transformation ratio to determine the second transformation ratio includes: calculating the target input voltage of the LLC resonance conversion unit when the LLC resonance conversion circuit is in the first transformation ratio; calculating the DC conversion The first voltage difference between the input voltage of the converter and the target input voltage is determined; the transformation ratio between the first voltage difference and the output voltage of the DC converter is determined as the second transformation ratio.
  • the first voltage regulating circuit is used to transmit when the LLC resonant conversion unit is at the maximum transformation ratio with The difference voltage of the total input voltage realizes the fine-tuning of the voltage.
  • the LLC resonant conversion unit is controlled to be at the first transformation ratio
  • the first voltage regulating circuit is controlled to be at the second transformation ratio.
  • the LLC resonance conversion unit includes: an inverter circuit, a resonance circuit, a transformer and a rectifier circuit, and the LLC resonance conversion unit is controlled to be in a first transformation ratio, including:
  • a drive signal is sent to the inverter circuit to control the LLC resonance conversion unit to be in the first transformation ratio.
  • the cycle of the AC voltage output by the inverter circuit is the same as the resonant cycle of the resonant circuit.
  • the efficiency of the LLC resonant conversion unit can be improved because the cycle of the alternating current output by the inverter circuit in the LLC resonant conversion unit is consistent with the resonant cycle of the resonant circuit.
  • the on-time sequence of the switch tube is changed by changing the drive signal, so as to expand the transformation ratio range of the LLC resonant conversion unit.
  • an embodiment of the present application provides a DC converter, where the DC converter mainly includes an LLC resonant conversion unit and a first voltage regulating circuit.
  • the LLC resonant conversion unit includes a first input end, a second input end, a first output end and a second output end, and the first voltage regulating circuit includes a third input end, a fourth input end, a third output end and a fourth output end output.
  • the second input terminal is connected to the third input terminal
  • the first output terminal is connected to the third output terminal
  • the second output terminal is connected to the fourth output terminal.
  • the LLC resonance conversion unit may include an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
  • the inverter circuit is used to convert the first input voltage received through the first input terminal and the second input terminal into an AC voltage, and the AC voltage is transmitted through the resonant circuit and the transformer to a rectifier circuit, and the rectifier circuit converts the AC voltage output by the transformer.
  • the voltage is converted into the output voltage of the DC converter, and the output voltage of the DC converter is output through the first output terminal and the second output terminal;
  • the LLC resonance conversion unit has a plurality of voltage conversion gears;
  • the first voltage regulation circuit is used to The second input voltage received by the third input terminal and the fourth input terminal is converted into the output voltage of the DC converter, and the output voltage of the DC converter is output through the third output terminal and the fourth output terminal, and the total input voltage of the conversion circuit is Including a first input voltage and a second input voltage.
  • the LLC resonant conversion unit and the input side of the first voltage regulating circuit are connected in series, and the output side is connected in parallel.
  • the efficiency of the LLC resonant conversion unit is a%
  • the efficiency of the first voltage regulator circuit is b%
  • the DC converter provided by the embodiment of the present application has a Efficiency can be expressed as (a%-b%)*(N1*Vo)/Vi+b%, since when the ratio of the LLC resonant conversion unit is larger, the efficiency of the DC converter will be higher, by adjusting the LLC resonant conversion unit
  • the highest voltage conversion gear is achieved to achieve the maximum transformation ratio, which is beneficial to improve the efficiency of the DC converter.
  • the period of the AC voltage output by the inverter circuit is the same as the resonance period of the resonant circuit, and the LLC resonant conversion The output voltage of the cell is greater than zero.
  • the voltage conversion efficiency of the LLC resonant conversion unit is greater than the voltage conversion efficiency of the first voltage regulating circuit, and the voltage conversion efficiency of the LLC resonant conversion unit is the output power of the LLC resonant conversion unit and the LLC resonant conversion unit.
  • the ratio of the input power, the voltage conversion efficiency of the first voltage regulating circuit is the ratio of the output power of the first voltage regulating circuit to the input power of the first voltage regulating circuit.
  • the controller In one possible implementation, the controller.
  • the controller is used to control the LLC resonant conversion unit to convert the first input voltage into the output voltage of the DC converter, control the first voltage regulating circuit to convert the second input voltage to the output voltage of the DC converter;
  • the target transformation ratio adjust the voltage conversion gear of the LLC resonance conversion unit.
  • the target transformation ratio is the ratio between the total input voltage and the target output voltage of the DC converter.
  • the LLC resonance conversion unit includes: an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
  • the two input ends of the inverter circuit respectively form the first input end and the second input end, one output end of the inverter circuit is connected to one end of the resonant circuit, and the other output end of the inverter circuit is connected to one end of the primary winding of the transformer
  • the other end of the resonant circuit is connected to the other end of the primary winding of the transformer; the two ends of the secondary winding of the transformer are respectively connected to the two input ends of the rectifier circuit; the two output ends of the rectifier circuit respectively form the first output end and the second output.
  • the inverter circuit has a plurality of voltage conversion ratios, and the plurality of voltage conversion ratios are one-to-one with the plurality of voltage conversion gears of the plurality of voltage conversion units of the LLC resonance conversion unit.
  • the adjustable conversion ratio of LLC resonant conversion unit can be realized by adjusting the conversion ratio of the inverter circuit, which is beneficial to control the LLC resonant conversion unit to be in a larger conversion ratio and transmit more power , further improving the efficiency of the DC converter.
  • the inverter circuit has at least the following possible implementations:
  • the inverter circuit includes: an H bridge circuit and a first capacitor.
  • the first end of the first bridge arm of the H-bridge circuit forms the first input end, the second end of the first bridge arm is connected to one end of the resonant circuit, and the first end of the second bridge arm of the H-bridge circuit forms the second end
  • the input end, the first end of the second bridge arm forms the second input end of the resonant circuit, the second end of the second bridge arm is connected with the second end of the first bridge arm, and the H bridge circuit is used to receive the first drive signal , and adjust the voltage conversion gear of the LLC resonance conversion unit according to the first driving signal;
  • the first capacitor is connected across the middle node of the first bridge arm and the middle node of the second bridge arm.
  • the on-time sequence of the switch tube in the H-bridge circuit can be controlled by the received drive signal, so as to control the charging and discharging of the first capacitor, so that the inverter circuit can output different voltage values, so as to realize the adjustment of LLC resonance conversion. unit ratio.
  • the inverter circuit includes: a flying capacitor type multi-level half-bridge inverter circuit, a first switch tube and a second switch tube.
  • the first input terminal of the flying capacitor type multilevel half-bridge inverter circuit forms the first input terminal
  • the second input terminal of the flying capacitor type multilevel inverter circuit forms the second input terminal
  • the first output terminal of the flying capacitor type multi-level half-bridge inverter circuit is connected to the first terminal of the first switch tube
  • the second output terminal of the flying capacitor type multi-level half-bridge inverter circuit is connected to the second switch tube
  • the first end of the flying capacitor type multi-level half-bridge inverter circuit is used to receive the second driving signal, and according to the second driving signal, adjust the voltage conversion gear of the LLC resonant conversion unit;
  • the two ends are connected to one end of the resonant circuit;
  • the second end of the second switch tube is connected to the second end of the first switch tube.
  • the on-time sequence of the switching tubes in the flying capacitor type multi-level half-bridge inverter circuit can be controlled by the received driving signal, so as to control the charging and discharging of multiple flying capacitors, so as to realize the output of the inverter circuit.
  • Different voltage values can be used to adjust the transformation ratio of the LLC resonant conversion unit.
  • the LLC resonant conversion unit when the transformation ratio of a single LLC resonant conversion unit is limited, in order to further improve the conversion efficiency of the DC converter, the LLC resonant conversion unit includes N LLC resonant conversion circuits. Wherein, each LLC resonant conversion circuit in the N LLC resonant conversion circuits has a plurality of voltage conversion gears. where N is an integer greater than or equal to 2.
  • the input terminals of the N LLC resonant conversion circuits are connected in series to form the first input terminal and the second input terminal, and the output terminals of the N LLC resonant conversion circuits are connected in parallel to form the first output terminal and the second output terminal.
  • the DC converter may further include: a plurality of third switch tubes, a plurality of fourth switch tubes, and a plurality of fifth switch tubes.
  • each third switch is connected across the first terminals of the input ends of two adjacent LLC resonant conversion circuits; each fourth switch is connected across the first end of the input ends of the adjacent two LLC resonant conversion circuits. between two terminals; one end of each fifth switch is connected to the second terminal of the input end of the first LLC resonant conversion unit in two adjacent LLC resonant conversion circuits, and the other end of the fifth switch is connected to two adjacent LLCs
  • the first terminal of the input end of the second LLC resonance conversion unit in the resonance conversion circuit is connected.
  • the first endpoint is the end of the LLC resonant conversion circuit that receives the high level
  • the second endpoint is the end of the LLC resonant conversion circuit that receives the low level.
  • the input sides of multiple LLC resonant conversion circuits can be changed from series to parallel, so as to adjust the LLC resonance
  • the transformation ratio of the conversion unit that is, the transformation ratio is adjusted in real time with the application scenario.
  • the DC converter further includes: a second voltage regulating circuit with higher conversion efficiency.
  • the input end of the second voltage regulating circuit is connected in series with the input end of the first voltage regulating circuit and the input end of the LLC resonant conversion unit respectively to form the first input end and the second input end, and the output end of the second voltage regulating circuit is respectively connected with the input end of the LLC resonant conversion unit.
  • the output end of the first voltage regulating circuit and the output end of the LLC resonant conversion circuit are connected in parallel to form the first output end and the second output end.
  • the first voltage regulation circuit may be a Buck circuit.
  • an embodiment of the present application provides a DC converter, where the DC converter mainly includes an LLC resonant conversion unit and a first voltage regulating circuit.
  • the LLC resonance conversion unit includes a first input end, a second input end, a first output end and a second output end.
  • the first voltage regulating circuit includes a third input terminal, a fourth input terminal, a third input terminal and a fourth output terminal.
  • the LLC resonance conversion unit includes an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
  • the second output terminal is connected to the third output terminal
  • the first input terminal is connected to the third input terminal
  • the second input terminal is connected to the fourth input terminal.
  • the inverter circuit can be used to convert the input voltage of the DC converter received through the first input terminal and the second input terminal into an AC voltage, and the AC voltage can be transmitted to the rectifier circuit through the resonant circuit and the transformer, and the rectifier circuit outputs the output of the transformer.
  • the AC voltage is converted into the first output voltage and output through the first output terminal and the second output terminal;
  • the LLC resonant conversion unit has multiple voltage conversion gears;
  • the first voltage regulating circuit is used to The input voltage of the DC converter received by the four input terminals is converted into a second output voltage and output through the third input terminal and the fourth output terminal.
  • the total output voltage of the DC converter includes the first output voltage and the second output voltage.
  • the LLC resonant conversion unit is connected in parallel with the input side of the first voltage regulator circuit, and the output side is connected in series, which is mainly used in boost application scenarios, and has similar technical effects as the second aspect.
  • the third aspect For the technical effect of the corresponding solution, reference may be made to the technical effect that can be obtained by the corresponding solution in the second aspect, and the repeated parts will not be described in detail.
  • the period of the AC voltage output by the inverter circuit is the same as the resonance period of the resonant circuit, and the LLC resonant conversion The output voltage of the cell is greater than zero.
  • the voltage conversion efficiency of the LLC resonant conversion unit is greater than that of the voltage regulator circuit, and the voltage conversion efficiency of the LLC resonant conversion unit is the difference between the output power of the LLC resonant conversion unit and the input power of the LLC resonant conversion unit
  • the voltage conversion efficiency of the voltage regulator circuit is the ratio of the output power of the voltage regulator circuit to the input power of the voltage regulator circuit.
  • the DC converter further includes: a controller.
  • the controller is used to control the LLC resonant conversion unit to convert the input voltage of the DC converter into the first output voltage, and control the voltage regulating circuit to convert the input voltage of the DC converter to the second output voltage; ratio, adjust the voltage conversion gear of the LLC resonant conversion unit.
  • the target transformation ratio is the ratio of the input voltage to the target output voltage.
  • an embodiment of the present application provides a conversion system, where the conversion system mainly includes a DC converter and a controller.
  • the DC converter mainly includes an LLC resonant conversion unit and a first voltage regulation circuit
  • the LLC resonant conversion unit has multiple voltage conversion gears
  • the LLC resonant conversion unit includes a first input end, a second input end, and a first output end and a second output terminal
  • the first voltage regulating circuit includes a second input terminal, a third input terminal, a third output terminal and a fourth output terminal.
  • the LLC resonance conversion unit includes an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
  • the second input terminal is connected to the third input terminal
  • the first output terminal is connected to the third output terminal
  • the second output terminal is connected to the fourth output terminal.
  • the controller is respectively connected with the LLC resonance conversion unit and the first voltage regulating circuit, and the controller can be used for: controlling the inverter circuit to convert the first input voltage received through the first input terminal and the second input terminal into an AC voltage , the AC voltage is transmitted to the rectifier circuit through the resonant circuit and the transformer, and the rectifier circuit converts the AC voltage output by the transformer to the output voltage of the system, and outputs the output voltage of the DC converter through the first output terminal and the second output terminal;
  • a voltage regulating circuit converts the second input voltage received through the third input terminal and the fourth input terminal into the output voltage of the conversion system, and outputs the output voltage of the DC converter through the third output terminal and the fourth output terminal, the DC
  • the total input voltage of the converter includes a first input voltage and a second input voltage.
  • the LLC resonant conversion unit can be configured with a suitable maximum transformation ratio from multiple voltage conversion gears through the controller, so that the LLC resonant conversion unit can transmit more power.
  • the efficiency of the voltage circuit is beneficial to improve the efficiency of the conversion system.
  • the embodiments of the present application provide an electronic device, and the electronic device may include a power supply and the DC converter provided in the foregoing embodiments.
  • the DC converter can be connected with the power supply, and the DC converter can convert the voltage output by the power supply into the supply voltage of the load.
  • the electronic device can be powered on and off.
  • the electronic device may be an on-board charger.
  • the efficiency of the electronic device can be improved by the aforementioned DC converter.
  • FIG. 1 is a schematic diagram 1 of a two-stage converter architecture structure
  • FIG. 2 is a schematic diagram 2 of a two-stage converter architecture structure
  • FIG. 3 is a schematic structural diagram of an LLC resonant conversion unit
  • FIG. 4 is a schematic structural diagram 1 of a DC converter provided by an embodiment of the present application.
  • FIG. 5 is a second structural schematic diagram of a DC converter provided by an embodiment of the present application.
  • FIG. 6 is a schematic flowchart of a method for adjusting the transformation ratio of a DC converter provided by an embodiment of the present application
  • FIG. 7 is a schematic flowchart of a specific method for adjusting the transformation ratio of a DC converter provided by an embodiment of the present application.
  • FIG. 8 is a schematic diagram of a process for determining a variable ratio change provided by an embodiment of the present application.
  • FIG. 9 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the present application.
  • FIG. 10 is a schematic diagram of a driving signal provided by an embodiment of the present application.
  • FIG. 11 is a schematic diagram of a switching state of an LLC resonant conversion unit provided by an embodiment of the application.
  • FIG. 12 is a schematic diagram of an equivalent circuit of an LLC resonant conversion unit provided by an embodiment of the application.
  • FIG. 13 is a schematic diagram of a switching state of an LLC resonant conversion unit provided by an embodiment of the application.
  • 15 is a schematic diagram of a switching state of an LLC resonant conversion unit provided by an embodiment of the application.
  • 16 is a schematic diagram of an equivalent circuit of an LLC resonant conversion unit provided by an embodiment of the application.
  • FIG. 17 is a schematic diagram of a driving signal provided by an embodiment of the present application.
  • FIG. 18 is a schematic diagram of a switching state of an LLC resonant conversion unit provided by an embodiment of the application.
  • 19 is a schematic diagram of an equivalent circuit of an LLC resonant conversion unit provided by an embodiment of the application.
  • 20 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application.
  • 21 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application.
  • FIG. 22 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application.
  • FIG. 23 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application.
  • FIG. 24 is a schematic diagram of a driving signal provided by an embodiment of the application.
  • 25 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application.
  • FIG. 26 is a schematic structural diagram of a first voltage regulation circuit provided by an embodiment of the application.
  • FIG. 27 is a schematic structural diagram of a first voltage regulating circuit provided by an embodiment of the application.
  • 29 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application.
  • FIG. 30 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application.
  • FIG. 31 is a schematic structural diagram of another DC converter according to an embodiment of the present application.
  • connection in the embodiments of the present application refers to an electrical connection, and the connection of two electrical elements may be a direct or indirect connection between the two electrical elements.
  • connection between A and B can be either a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components, such as the connection between A and B, or the direct connection between A and C, C and B are directly connected, and A and B are connected through C.
  • the "transformation ratio" of the conversion circuit in the embodiments of the present application refers to the ratio between the larger voltage of the input voltage and the output voltage of the conversion circuit and the smaller voltage of the input voltage and the output voltage. If the conversion circuit performs step-down conversion, the output voltage of the conversion circuit is smaller than the input voltage of the conversion circuit, and the transformation ratio of the conversion circuit is input voltage/output voltage. If the conversion circuit performs boost conversion, the output voltage of the conversion circuit is greater than the input voltage of the conversion circuit, and the conversion ratio of the conversion circuit is output voltage/input voltage.
  • switch-mode converters With the development of the power electronics field, switch-mode converters have been widely used. Accordingly, the design of switch-mode converters also faces the requirements of comprehensive performance such as high power density, high efficiency and fast dynamic characteristics. In order to achieve higher power density, the method of increasing the switching frequency is usually used to reduce the volume of magnetic components such as capacitors, inductors, and transformers in the converter. efficiency of the device.
  • the LLC resonant converter mainly includes: an inverter circuit, a resonant circuit, a transformer and a rectifier circuit.
  • the first output end of the inverter circuit is connected to one end of the resonant circuit, the other output end of the inverter circuit is connected to one end of the primary winding of the transformer; the other end of the resonant circuit is connected to the other end of the primary winding of the transformer; the transformer Two ends of the secondary winding are respectively connected with two input ends of the rectifier circuit.
  • the switching tube in the inverter circuit usually works at a switching frequency of 50% duty cycle, and the transformation ratio of the entire LLC resonant converter can be controlled by adjusting the switching frequency of the switching tube.
  • the LLC resonant converter can achieve soft switching and low conduction losses when operating at the resonant frequency of the resonant circuit, where it has maximum efficiency.
  • the LLC resonant converter is less efficient as the switching frequency deviates further from the resonant frequency.
  • the conduction sequence and switching frequency of the switch tube in the inverter circuit are fixed, so that the switching frequency of the switch tube in the inverter is consistent with the resonant frequency of the resonant circuit, so as to achieve the maximum efficiency, in this case the ratio of the LLC resonant conversion circuit is fixed.
  • the converter needs to output different transformation ratios to meet the operation of the power supply at different transformation ratios.
  • Single-stage LLC The transformation ratio of the resonant conversion converter has been difficult to meet the power supply requirements of the power supply. Based on this, the power supply architecture of the two-stage converter is set up.
  • the LLC resonant converter has a fixed voltage conversion gear, and the Buck circuit is used to convert the voltage that the LLC resonant converter cannot convert to realize voltage adjustment.
  • the efficiency of the LLC resonant converter is 97%
  • the efficiency of the Buck circuit is 88%
  • the transformation ratio of the LLC resonant converter is 30,
  • the input voltage of the two-stage converter power supply architecture shown in Figure 2 is [40-60]V
  • the output voltage varies within the range of [0.6-1.2]V.
  • the total efficiency of the two-level converter power supply architecture is 36/40*97%+4/40*88% ⁇ 96%; when the input voltage under the two-level converter power supply architecture is 60V, and the output voltage is 0.6 At V, the output voltage of the LLC resonant converter is 18V, the output voltage is 0.6V, the input voltage of the Buck circuit is 42V, and the output voltage is 0.6V, at this time, the total efficiency of the two-stage converter power supply architecture is 18/60*97 %+42/60*88% ⁇ 91%. Therefore, in the converter structure shown in FIG. 2 , when the ratio of the input voltage borne by the LLC resonant converter to the input voltage of the two-stage converter power supply structure is smaller, the
  • the present application provides a DC converter, which can be applied to a switching power supply, which can not only meet the transformation ratio requirements of the switching power supply, but also help improve the efficiency of the switching power supply.
  • the DC converter 400 provided by the embodiment of the present application mainly includes an LLC resonant conversion unit 401 and a first voltage regulation circuit 402 .
  • the LLC resonance conversion unit 401 includes a first input end 11 , a second input end 12 , a first output end 13 and a second output end 14 .
  • the first voltage regulating circuit 402 includes a third input terminal 21 , a fourth input terminal 22 , a third output terminal 23 and a fourth output terminal 24 .
  • the first input terminal 11 and the second input terminal 12 of the LLC resonant conversion unit 401 are used to receive the first input voltage Vi1 of the DC converter 400
  • the third input terminal 21 and the fourth input terminal of the first voltage regulating circuit 402 22 is used for receiving the second input terminal voltage Vi2 of the DC converter 400
  • the first input voltage Vi1 and the second output voltage Vi2 constitute the total input voltage Vi of the DC converter 400 . That is, the input side (the first input terminal 11 and the second input terminal 12 ) of the LLC resonance conversion unit 401 is connected in series with the input side (the third input terminal 21 and the fourth input terminal 22 ) of the first voltage regulating circuit 402 .
  • the LLC resonant conversion unit 401 and the input side of the first voltage regulator circuit 402 have the same input current. Meanwhile, as shown in FIG. 4 , the voltage between the input terminals 11 and 12 is Vi1, the voltage between the input terminal 21 and the input terminal 22 is Vi2, and the sum of the input voltage Vi1 and the input voltage Vi2 is the total of the DC converter 400. Input voltage Vi.
  • both the LLC resonance conversion unit 401 and the first voltage regulation circuit 402 can implement a voltage conversion function.
  • the LLC resonance conversion unit 401 can convert the input voltage Vi1 and output the converted voltage through the output terminal 13 and the output terminal 14 .
  • the first voltage regulating circuit 402 can convert the input voltage Vi2 and output the converted voltage through the output terminal 23 and the output terminal 24 .
  • the LLC resonance conversion unit 401 includes an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
  • the inverter circuit converts the input voltage Vi1 received through the input terminals 11 and 12 into an AC voltage, and transmits the AC voltage to the rectifier circuit through the resonant circuit and the transformer.
  • the AC power output by the transformer is converted into DC voltage and then output.
  • the output terminal of the LLC resonant conversion unit 401 is connected to the output terminal of the first voltage regulator circuit 402
  • the output terminal 13 of the LLC resonant conversion unit 401 is connected to the output terminal 23 of the first voltage regulator circuit 402
  • the LLC resonates
  • the output terminal 14 of the conversion unit 401 is connected to the output terminal 24 of the first voltage regulating circuit 402 , that is, the output side (the first output terminal 13 and the second output terminal 14 ) of the LLC resonance conversion unit 401 is connected to the first voltage regulating circuit 402
  • the output side (the third output terminal 23 and the fourth output terminal 24 ) of the DC converter are connected in parallel, so the output voltage Vo of the LLC resonant conversion unit 401 and the first voltage regulating circuit 402 is the same, and the output voltage Vo is the output voltage of the DC converter 400 .
  • the DC converter 400 provided by the embodiments of the present application has high conversion efficiency.
  • the input current of the DC converter 400 is Ii and the output current is Io.
  • the output current of the LLC resonant conversion unit 401 is Io1
  • the efficiency a% of the LLC resonant conversion unit 401 can be understood as the ratio of the output power of the LLC resonant conversion unit 401 to the input power of the LLC resonant conversion unit 401 (mostly expressed in the form of a percentage). ), a can be any value greater than or equal to 0 and less than or equal to 100.
  • the efficiency of the LLC resonant conversion unit satisfies the following formula 1:
  • the efficiency b% of the first voltage regulating circuit 402 can be understood as the ratio of the output power of the first voltage regulating circuit 402 to the input power of the first voltage regulating circuit 402 (more than In the form of percentage), b can be any value greater than or equal to 0 and less than or equal to 100.
  • the efficiency of the first voltage regulating circuit satisfies the following formula 2:
  • ⁇ represents the efficiency of the DC converter 400 .
  • formula three the following formula four can be obtained:
  • the period of the AC voltage output by the inverter circuit and the resonance period of the resonant circuit are The same, and the output voltage of the LLC resonant conversion unit is greater than zero.
  • the LLC resonant conversion unit 401 and the first voltage regulating circuit 402 may be composed of devices such as switch tubes, diodes, inductors, and capacitors.
  • the working states of the LLC resonant conversion unit 401 and the first voltage regulator circuit 402 can be adjusted by adjusting the work states of these devices (eg, switches) to adjust the transformation ratio of the LLC resonant conversion unit 401 and the first voltage regulator circuit 402 .
  • the DC converter 400 may further include a controller 403.
  • the controller 403 is respectively connected to the LLC resonant conversion unit 401 and the first voltage regulating circuit 402, and can be used to control the LLC resonant conversion unit 401 to convert the An input voltage Vi1 is converted into the output voltage V0 of the DC converter 400, the first voltage regulation voltage 402 is controlled to convert the second input voltage Vi2 into the output voltage Vo of the DC converter 400, and according to the target transformation ratio of the DC converter, the adjustment The voltage conversion gear of the LLC resonance conversion unit 401 .
  • the target transformation ratio is the ratio between the total input voltage and the target output voltage of the DC converter.
  • the controller 403 can be connected to the gate of the MOS transistor to control the on-off of the MOS transistor.
  • MOS metal oxide semiconductor
  • the controller 403 can be connected to the base of the BJT, from the control The on-off of the BJT enables the DC converter 400 to realize voltage conversion.
  • the controller 403 may be any one of a microcontroller unit (microcontroller unit, MCU), a central processing unit (central processing unit, CPU), and a digital signal processor (digital signal processor, DSP).
  • MCU microcontroller unit
  • CPU central processing unit
  • DSP digital signal processor
  • the specific form of the controller 403 is not limited to the above examples.
  • the switching frequencies of the LLC resonant conversion unit 401 and the first voltage regulator circuit 402 do not need to be consistent.
  • the efficiency a% of the LLC resonant conversion unit 401 is greater than the efficiency b% of the first voltage regulating circuit 402, and the larger the value of the first transformation ratio N1, the higher the efficiency of the DC converter 400.
  • the controller 403 can make the LLC resonant conversion unit 401 have a larger transformation ratio, and make the first voltage regulation circuit 402 have a higher transformation ratio. Small ratio.
  • the loss of the first voltage regulating circuit 402 is mainly generated during the voltage conversion process, so when the second transformation ratio N2 is 1, it can be considered that the first voltage regulating circuit 402 has the smallest loss and transmits less power.
  • the voltage regulating range of the first voltage regulating circuit can be increased.
  • the transformation ratio N2 of the first voltage regulating circuit 402 can be made smaller than 1 and close to 0, that is to say, the smaller the input voltage Vi2 of the first voltage regulating circuit 402 is, the less power the first voltage regulating circuit 402 transmits .
  • the efficiency a% of the LLC resonant conversion unit 401 is greater than the efficiency b% of the first voltage regulating circuit 402, configuring a larger transformation ratio for the LLC resonant conversion unit 402 can make the LLC resonant conversion unit 401 Transmitting more power is beneficial to further improve the efficiency of the DC converter 400 .
  • the transformation ratio of the LLC resonant conversion unit 401 often needs to be dynamically changed with changes in the application scenarios.
  • the first transformation ratio N1 and the second transformation ratio N2 are adjustable.
  • the controller 403 may also detect the current total input voltage Vi and the target output voltage Va of DC conversion.
  • the current total input voltage Vi may be the output voltage of the battery connected to the DC converter 400
  • the target output voltage Va of the DC converter 400 may be the operating voltage currently required by the load.
  • the battery voltage will gradually decrease during the discharge of the connected battery.
  • the loads connected to the output terminal 13 and the output terminal 14 may have various working states, and the required working voltages are different in different working states.
  • the load may be a GPU or a battery, and during the charging process of the battery, the voltage at both ends of the battery gradually increases.
  • the output voltage Vo of the DC converter 400 may be the same as the target output voltage Va, or may be different from the target output voltage Va.
  • the controller can adjust the transformation ratio of the DC converter, so as to adjust the output voltage Vo of the DC converter to the desired target output voltage Va.
  • the target output voltage is the voltage actually required by the load.
  • the controller 403 may detect the current output voltage Vo and the total input voltage Vi.
  • the controller 403 can adjust the transformation ratio of the LLC resonant conversion unit 401 and the first voltage regulating circuit 402 according to the total input voltage Vi, so as to convert the DC converter
  • the output voltage Vo of 400 is adjusted to the target output voltage Va.
  • the controller 403 can execute the control method shown in FIG. 6 to adjust the transformation ratio of the LLC resonant conversion unit 401 and the first voltage regulation circuit 402 in FIG. 4 to improve the conversion efficiency of the DC converter 400 , which mainly includes the following: step:
  • S601 Calculate a target transformation ratio, where the target transformation ratio is the transformation ratio between the input voltage of the DC converter 400 and the target output voltage of the DC converter.
  • S602 According to the target transformation ratio and the minimum transformation ratio of the first voltage regulating circuit, determine the first transformation ratio of the LLC resonance transformation unit from a plurality of voltage transformation gears of the LLC resonance transformation unit.
  • the first transformation ratio N1 is less than or equal to the difference between the target transformation ratio Na and the minimum transformation ratio of the first voltage regulating circuit 402 , and is less than or equal to the maximum transformation ratio of the LLC resonance conversion unit 401 .
  • the controller 403 can change the voltage conversion gear of the LLC resonant conversion unit 401 by controlling the timing and switching frequency of the driving signal of the switch tube in the inverter circuit of the LLC resonant conversion unit 401 , so as to adjust the first transformation ratio N1.
  • the specific value of N1 determined by the controller is related to the structure of the LLC resonant conversion unit, and the controller can flexibly select an implementation manner of setting the transformation ratio of the LLC resonant conversion unit according to the specific structure of the LLC resonant conversion unit.
  • S603 Determine the second transformation ratio N2 of the first voltage regulating circuit 402 according to the first transformation ratio N1 and the target transformation ratio.
  • the controller may flexibly select an implementation manner of setting the transformation ratio of the first voltage regulating circuit 402 according to the specific structure of the first voltage regulating circuit 402 .
  • the embodiments of the present application describe the control method shown in FIG. 6 by taking the case where the efficiency of the LLC resonant conversion unit is a% and the efficiency of the first voltage regulating circuit is b% as an example.
  • the first transformation ratio N1 has a plurality of non-continuously adjustable transformation ratios, and each transformation ratio corresponds to the first voltage transformation gear of the LLC resonant conversion unit 401 .
  • the first transformation ratio N1 may be a ratio smaller than the target transformation ratio Na and the first variable ratio N1 among the multiple adjustable ratios in the LLC resonance transformation unit The difference of the minimum transformation ratio of the voltage regulating circuit 402 and the adjustable transformation ratio closest to the target transformation ratio Na.
  • the controller 403 can use the variable ratio shown in FIG. 7 . method, adjust the first transformation ratio N1 and the second transformation ratio N2. As shown in Figure 7, it mainly includes the following steps:
  • the controller calculates the target transformation ratio Na.
  • S703 Detect whether the first voltage regulating circuit has a boosting function, if yes, go to 704 , otherwise go to 705 .
  • each voltage conversion gear corresponds to a first voltage transformation ratio N1.
  • the second transformation ratio N2 of the first voltage regulating circuit can be close to 0, at this time.
  • the first transformation ratio N1 (Vi ⁇ Vi2)/Va ⁇ Na. That is to say, in an ideal situation, the second transformation ratio N2 ⁇ 0. Therefore, the value range of the first transformation ratio N1 is N1 ⁇ Na, and N1 is smaller than or the maximum voltage conversion gear of the LLC resonance conversion unit.
  • the second transformation ratio N2 of the first voltage regulating circuit can reach 1 under ideal conditions.
  • Vi2 Va
  • S706 Determine the largest voltage conversion gear within the value range of the voltage conversion gears of the LLC resonance conversion unit as the first transformation ratio.
  • the LLC resonant conversion unit has three voltage conversion gears of 3, 2, and 1.
  • the total input voltage Vi is 3.4V
  • the target output voltage Va is 1V.
  • the target transformation ratio Na is 3.4.
  • S707 Calculate the target input voltage of the LLC resonance conversion unit when the LLC resonance conversion unit is in the first transformation ratio.
  • S708 Calculate a first voltage difference between the input voltage of the DC converter and the target input voltage.
  • S709 Determine a transformation ratio between the first voltage difference and the output voltage of the DC converter as the second transformation ratio.
  • the controller 403 can flexibly adjust the LLC resonant conversion unit 401 and the first voltage regulation according to the total input voltage Vi and the target output voltage Va of the DC converter
  • the transformation ratio of the circuit enables the LLC resonant conversion unit 401 to receive a larger input voltage Vi1 as much as possible while adapting to the application scenarios under different application scenarios of the total input voltage Vi and the target output voltage Va.
  • the method of setting the first transformation ratio N1 and the second transformation ratio N2 shown in FIG. 6 and FIG. 8 can be used to reconfigure the transformation ratios of the LLC resonant conversion unit 401 and the first voltage regulating circuit.
  • the output voltage Vo and the target output voltage Va can be achieved by adjusting the transformation ratio of the first voltage regulating circuit 402 .
  • the DC converter provided by the embodiment of the present application when used to supply power to the load, if the load connected to the output terminals 13 and 14 of the DC converter increases, the output voltage Vo of the DC converter is smaller than the target output voltage Va.
  • the duty ratio of the switch tube in the first voltage regulation circuit 402 can be adjusted to adjust the transformation ratio N2 of the first voltage regulation voltage 402 , so as to adjust the output voltage Vo until the output voltage Vo is equal to the target output voltage Va.
  • the DC converter provided in the embodiment of the present application when used to supply power to the load, if a battery is connected to the input side of the DC converter, the voltage of the battery is gradually reduced during the process of supplying power to the load, resulting in the voltage of the DC converter. If the output voltage Vo of the variable ratio deviates from the target output voltage Va, the duty cycle of the switch tube in the first voltage regulation circuit 402 can be adjusted to realize the adjustment of the transformation ratio N2 of the first voltage regulation voltage 402, so as to realize the adjustment of the output voltage Vo until the output is The voltage Vo is equal to the target output voltage Va.
  • the LLC resonant conversion unit 401 has various possible implementation structures.
  • the embodiments of the present application further illustrate the DC converter 400 provided by the embodiments of the present application by using the following examples.
  • the inverter circuit in the LLC resonance conversion unit 401 includes: a first capacitor C1 and a first H-bridge circuit composed of four switch tubes S1, S2, S3, and S4.
  • the resonant circuit mainly includes: the resonant inductor includes Lr and the resonant capacitor Cr.
  • the primary winding of the transformer is connected in series with the resonant inductor Lr and the resonant capacitor Cr, and the secondary winding of the transformer is connected with the rectifier circuit composed of the second H-bridge circuit.
  • the second H-bridge circuit mainly includes switch tubes S5, S6, S7 and S8.
  • the resonant inductance Lr may be an independent inductance, or may be the leakage inductance of the primary winding of the transformer, or the resonant inductance Lr is composed of a part of the independent inductance and a part of the leakage inductance of the primary winding of the transformer.
  • Lm is the excitation winding of the transformer.
  • S1 and S2 are connected in series to form the first bridge arm of the first H-bridge circuit
  • S3 and S4 are connected in series to form the second bridge arm of the first H-bridge circuit
  • C1 is connected between the middle node of the first bridge arm and the second bridge arm. between intermediate nodes. That is, the second end of S2 is connected to the first end of S1 and one end of C1 respectively, and the second end of S4 is connected to the first end of S3 and the other end of C2 respectively.
  • the first end of S1 is connected to the input end 11
  • the first end of S3 is connected to the input end 12 .
  • S5 and S6 are connected in series to form the first bridge arm of the second H-bridge circuit
  • S7 and S8 are connected in series to form the second bridge arm of the second H-bridge circuit. That is, the second end of S6 is connected to the first end of S5, the second end of S8 is connected to the first end of S7, the first end of S5 is respectively connected to the first end of S7 and one end of the secondary winding of the transformer, and the first end of S6
  • the second ends are respectively connected with the second end of S8 and the other end of the secondary winding of the transformer.
  • the middle node of the first bridge arm and the middle node of the second bridge arm of the second H-bridge circuit are respectively connected to the output end 12 and the output end 14 . That is, the second end of S5 is connected to the output end 13 , and the second end of S7 is connected to the output end 14 .
  • the second end of S2 and the second end of S4 are both connected to one end of the resonant capacitor Cr, the other end of Cr is connected to one end of the resonant inductor Lr, the other end of Lr is connected to one end of the primary winding of the transformer, and the primary winding of the transformer is connected.
  • the other end is connected to the input end 12 .
  • the first H-bridge circuit has a plurality of voltage conversion ratios, the plurality of voltage conversion ratios and the plurality of voltage conversion gears of the LLC resonance conversion unit 401 are one-to-one, and the plurality of voltage conversion ratios are one-to-one with the plurality of driving signals to one.
  • the driving signal is used to control the turn-on sequence of the switches S1 , S2 , S3 and S4 in the first H-bridge circuit.
  • the voltage conversion gear represents a ratio relationship between the input voltage of the LLC resonant conversion unit and the output voltage of the LLC resonant conversion unit, and the ratio relationship is the first transformation ratio N1 in the embodiment of the present application.
  • the LLC resonant conversion unit has multiple voltage conversion gears, which means that there are multiple voltages between the input voltage of the LLC resonant conversion unit and the output voltage of the LLC resonant conversion unit.
  • the ratio relationship for example, the plurality of ratio relationships are 1:1, 1.2:1, 1.5:1, and 2:1. Then under different voltage conversion gears, facing the same input voltage, the output voltage of the LLC resonant conversion unit is different.
  • the DC converter 400 may further include an input capacitor Cin1 and an input capacitor Cin2 .
  • One end of the input capacitor Cin1 is connected to the input end 11
  • the other end of the input capacitor Cin1 is connected to the input end 12
  • the input capacitor Cin1 can filter the first input voltage Vi1 .
  • One end of the input voltage Cin2 is connected to the input end 21
  • the other end of the input voltage Cin2 is connected to the input end 22
  • the Cin2 can filter the second input voltage Vi2 .
  • the DC converter 400 may further include an output capacitor Cout.
  • One end of the output capacitor Cout is connected to the output end 13 of the LLC resonance conversion unit 401 , and the other end of the output capacitor Cout is connected to the output end 14 of the LLC resonance conversion unit 401 .
  • the output capacitor Cout can filter the output voltage Vo to reduce the fluctuation of the output voltage Vo.
  • N1 2N h *N L (Formula 5)
  • Vh is the peak-to-peak value of the output voltage of the inverter circuit.
  • N h represents the transformation ratio between the input voltage Vi1 and the peak-to-peak value of the output voltage of the inverter circuit, and NL is the transformation ratio of the turns of the primary winding and the secondary winding of the transformer.
  • the LLC resonant conversion circuit When the switches S1 , S2 , S3 and S4 in the LLC resonant conversion circuit shown in FIG. 9 receive different driving signals, the LLC resonant conversion circuit is in different states and has different transformation ratios.
  • S1 , S2 , S3 and S4 receive different driving signals, the corresponding relationship between the driving signals and the output voltage of the first H-bridge circuit may be as shown in Table 1.
  • the LLC resonant conversion unit 401 shown in FIG. 9 uses the driving signals shown in Table 1 to drive the states of the switches S1 , S2 , S3 and S4 , the LLC resonant conversion unit has at least two adjustable ratios of 4 and 2.
  • the adjustable transformation ratio is the transformation ratio that the LLC resonant conversion unit 401 can theoretically achieve. Due to the parasitic resistance, parasitic inductance and other reasons, the difference between the actual transformation ratio of the LLC resonant transformation unit 401 and the adjustable transformation ratio is There may be some deviations, but it does not affect the realization of the technical solution of the present application.
  • the first implementation method the first transformation ratio N1 is 4.
  • each switch in the LLC resonant conversion unit 401 is turned on at high voltage and turned off at low voltage.
  • the controller 403 provides the drive signals as shown in FIG. 10 for each switch tube in the LLC resonant conversion unit 401 , the first transformation ratio N1 is 4. Among them, the controller sends drive signals in the order of states 2131 to control the switch tube to switch states.
  • the cycle of the alternating current is T, and the switches S1 , S2 , S3 and S4 correspond to different driving signals respectively.
  • each switch tube In the time period from 0 to T/2, the state of each switch tube can be as shown in FIG. 11 .
  • the switch S1 and the switch S3 are turned on, and the switches S2 and S4 are turned off.
  • the switch tube S1, the capacitor C1, the switch tube S3, Cr, Lr and Lm form a path, and the equivalent circuit can be shown in FIG. 12 .
  • V h is 1/2Vi1.
  • each switch tube In the time period from T/2 to T, the states of each switch tube may be as shown in FIG. 13 . Among them, the switch tubes S3 and S4 are turned on, and the switch tubes S1 and S2 are turned off.
  • each switch tube may be as shown in FIG. 15 .
  • the switch tubes S2 and S4 are turned on, and the switch tubes S1 and S3 are turned off.
  • the switches S4, Cr, S2, Lr, and Lm form a path, and the equivalent circuit can be shown in Figure 16.
  • the capacitor C1 discharges, because in the time period from 0 to T/2, C1 Both ends have been charged to 1/2Vi1, therefore, V h is 1/2Vi1, which will not be repeated here.
  • each switch tube In the time period from 3/2T to 2T, the state of each switch tube may be as shown in FIG. 13 . Among them, the switch tubes S1 and S2 are turned on, and the switch tubes S3 and S4 are turned off.
  • the switch tube S3, the switch tube S4, Cr, Lr and Lm form a path, and the equivalent circuit can be shown in FIG. 14 . Since the output terminal of the first H-bridge circuit is directly connected to the input terminal 12 , Vh is zero.
  • the switch is switched in the order of 2131.
  • the switching period of the switch two cycles of alternating current are output, that is, the switching period of the switch is twice the resonant period of the resonant circuit.
  • the second implementation mode the first transformation ratio N1 is 2.
  • each switch in the LLC resonant conversion unit is turned on at high voltage and turned off at low voltage.
  • the controller 403 provides the drive signals as shown in FIG. 17 for each switch tube in the LLC resonant conversion unit 401 , the first transformation ratio N1 is 2. Among them, the controller sends drive signals in the order of states 41, thereby controlling the switch tube to switch states.
  • each switch tube can be as shown in FIG. 18 .
  • the switch S1 and the switch S2 are turned on, and the switches S3 and S4 are turned off.
  • each switch tube In the time period from T/2 to T, the states of each switch tube may be as shown in FIG. 13 . Among them, the switch tubes S3 and S4 are turned on, and the switch tubes S1 and S2 are turned off.
  • the switch tube is switched in the order of 41, and in each switching cycle of the switch tube, one cycle of alternating current is output, that is, the switching cycle of the switch tube is the same as the resonant cycle of the resonant circuit.
  • the states of other driving signals in Table 1 can also be combined to obtain other adjustable ratios of the LLC resonant conversion unit, which are described in detail here in this application. It should be noted that, when the states of other driving signals are used for combination, the number of times of charging and discharging of the first capacitor C1 in each combination is the same.
  • the rectifier circuit may also adopt other circuit structures.
  • the rectifier circuit uses a half-bridge rectifier circuit with a center tap to supply power to the load, and the DC conversion circuit can use the circuit structure shown in FIG. 20 at this time.
  • a diode in order to solve the cost and volume of the device, can be used to replace the switch in the second H-bridge circuit.
  • the resonant capacitor in the resonant circuit can be split into two resonant capacitors C2 and C3 to achieve resonance with the resonant inductor Lr.
  • the sum of the capacitances of C1 and C2 is the capacitance of Cr.
  • the inverter circuit in the LLC resonant conversion unit 401 mainly includes a first switch tube S1, a second switch tube S2, a flying transistor composed of N first switch tubes, N second switch tubes and N flying capacitors.
  • Transcapacitive multi-level half-bridge inverter circuit The resonant circuit mainly includes the resonant inductor Lr and the resonant capacitor Cr. The primary winding of the transformer is connected in series with the resonant inductor Lr and the resonant capacitor Cr, and the secondary winding of the transformer is connected with the rectifier circuit composed of the H bridge.
  • the H-bridge circuit mainly includes switch tubes S3, S4, S5 and S6.
  • N is an integer greater than 1.
  • the first transfer switch tube is connected in series between the input end 11 and the first end of the switch tube S1 in sequence. That is, the second end of the i-th first transfer switch tube Si1 is connected to the first end of the i+1-th first transfer switch tube S(i+1)1, and the i-th first transfer switch tube Si1 The first end is connected to the second end of the i-1th first transfer switch tube S(i-1)1, and i takes values from 2 to N in sequence. Similarly, the first to the Nth second transfer switch tubes are connected in series between the input end 11 and the first end of the switch tube S2 in sequence. The first end of the first transfer switch S11 is connected to the input end 11 , and the first end of the first second transfer switch S12 is connected to the input end 12 .
  • the second end of S2 and the second end of S1 are both connected to one end of the resonant capacitor Cr, the other end of Cr is connected to one end of the resonant inductor Lr, the other end of Lr is connected to one end of the primary winding of the transformer, and the primary winding of the transformer is connected. The other end is connected to the input end 12.
  • S3 and S4 are connected in series to form the first bridge arm of the H bridge circuit
  • S5 and S6 are connected in series to form the second bridge arm of the H bridge circuit. That is, the second end of S4 is connected to the first end of S3, the second end of S6 is connected to the first end of S5, and the first end of S3 is respectively connected to the first end of S5 and one end of the secondary winding of the transformer, and the first end of S4
  • the second ends are respectively connected to the second end of S6 and the other end of the secondary winding of the transformer.
  • the middle node of the first bridge arm and the middle node of the second bridge arm of the H-bridge circuit are respectively connected to the output end 12 and the output end 14 . That is, the second end of S3 is connected to the output end 13 , and the second end of S5 is connected to the output end 14 .
  • the i-th first transfer switch tube Si1 and the i-th second transfer switch tube Si2 in the inverter circuit form a switch combination, and the inverter circuit may include N switch combinations. Wherein, the complementary conduction of the two switch tubes in each switch combination is conducted.
  • the flying capacitor mainly includes C1 and C2, the first transfer switch tubes S11 and S21, and the second transfer switch tubes S12 and S22.
  • the switch tube S21 and the output switch tube S22 belong to the same switch combination, S11 and S12 both belong to the same switch combination, and S1 and S2 both belong to the same output combination.
  • the switches in the LLC resonant conversion circuit shown in FIG. 23 receive different driving signals, the switches in the LLC resonant conversion unit are in different states and have different transformation ratios.
  • the corresponding relationship between the driving signal and the output voltage of the flying capacitor type multi-level half-bridge inverter circuit can be shown in Table 2.
  • the LLC resonant conversion unit shown in FIG. 23 uses the driving signal shown in Table 2 to drive the switches in the flying capacitor type multi-level half-bridge inverter circuit, the LLC resonant conversion unit has at least three types of 6, 3 and 2 Adjustable ratio.
  • the first implementation method the first transformation ratio N1 is 6.
  • each switch in the LLC resonant conversion unit is turned on at high voltage and turned off at low voltage.
  • the controller 403 provides the driving signals as shown in FIG. 24 for each switch tube in the LLC resonant conversion unit 401, the first transformation ratio N1 is 6. Among them, the driving signals are switched in the order of states 243756.
  • the flying capacitor type multi-level half-bridge inverter circuit uses the driving signal shown in Figure 24 to drive the switch, in the three cycles of the alternating current, the output of the inverter circuit in the three cycles of the alternating current output by the inverter circuit
  • the voltages are switched between 2Vi1/3 and Vi1/3, then the peak-to-peak value of the output voltage of the inverter circuit is Vi1/3, and the formula 5 and formula 6 are entered to obtain the transformation ratio N1 of the LLC resonant conversion unit 401 at this time as 6 .
  • the switch tube is switched in the order of 243756, and in each switching cycle of the switch tube, three cycles of alternating current are output, that is, the switching cycle of the switch tube is three times the resonant period of the resonant circuit.
  • the second implementation method the first transformation ratio N1 is 3.
  • each switch in the LLC resonant conversion unit is turned on at high voltage and turned off at low voltage.
  • the controller 403 switches the states of the respective switches in the LLC resonance conversion unit 401 in the order of states 416171, the LLC resonance conversion unit has a transformation ratio of 3.
  • the flying capacitor type multi-level half-bridge inverter circuit uses the above method to drive the signal to drive the switch, in the three cycles of the alternating current, the output voltage of the inverter circuit in the three cycles of the alternating current output by the inverter circuit is all within 2Vi1 /3 to 0, the peak-to-peak value of the output voltage of the inverter circuit is 2Vi1/3;
  • the switch is switched in the order of 416171.
  • the switching period of the switch is three times the resonant frequency period of the resonant circuit. .
  • the third implementation manner the first transformation ratio N1 is 2.
  • each switch in the LLC resonant conversion unit is turned on at high voltage and turned off at low voltage.
  • the controller 403 switches the states of the respective switches in the LLC resonance conversion unit 401 in the sequence of states 81, the LLC resonance conversion unit has a transformation ratio of 2.
  • the flying capacitor type multi-level half-bridge inverter circuit uses the above-mentioned driving signal to drive the switch, the output voltage of the inverter circuit is converted between 0 and Vi1 in the whole cycle of the alternating current, then the inverter circuit outputs The peak-to-peak value of the voltage is Vi1, and into formula 5 and formula 6, it is obtained that the transformation ratio of the LLC resonant conversion unit 401 is 2 at this time.
  • the switch tube is switched in the order of 81, and in each switching cycle of the switch tube, one cycle of alternating current is output, that is, the switching cycle of the switch tube is the same as the resonant frequency cycle of the resonant circuit.
  • the inverter circuit may include a first flying capacitor type multi-level half-bridge inverter circuit and a second flying capacitor type multi-level half-bridge inverter circuit. Ratio type used to increase the LLC resonant conversion unit.
  • the first transfer switch tube is connected in series between the input terminal 11 and the first end of the switch tube S1 in sequence, and the second transfer switch tube is connected in series. They are connected in series between the input end 12 and the first end of the switch tube S2 in sequence, and the second end of S1 and the second end of S2 are both connected to one end of the resonant circuit.
  • the first transfer switch is connected in series between the input end 11 and the first end of the switch S7, and the second transfer switch is connected in series with the input end 12.
  • the second end of S1 and the second end of S2 are both connected to the other end of the resonant circuit.
  • the process of changing the ratio of the LLC resonant conversion unit 401 by using the driving signal is the same as the process of Example 2 of the LLC resonant conversion unit of the present application, which will not be repeated in this application.
  • the first voltage regulating circuit 402 also has various possible implementation manners. Generally speaking, when the efficiency of the first voltage regulating circuit 402 is low, the first voltage regulating circuit may focus on finely regulating the output voltage Vo.
  • Example 1 of the first voltage regulating circuit is a first voltage regulating circuit
  • the first voltage regulation may be a Buck circuit.
  • the first voltage regulation voltage mainly includes a switch tube SH, a switch tube SL and an inductor L1 .
  • the first end of the switch tube SH can be used as the input end 21 of the first voltage regulating circuit, and is connected to the input end 12 of the LLC resonant conversion circuit 401 .
  • the second end of the switch tube SH is respectively connected to the first end of the switch tube SL and one end of the second adjusting inductor L2.
  • the second end of the switch tube SL can be used as the output end 24, connected to the input end 22 and grounded.
  • the other end of the second adjusting inductor L2 can be used as the output end 23 and is connected to the output end 13 of the LLC resonance conversion unit 401 .
  • the inductor L1 switches between energy storage and energy release for a long time, that is, the current flowing through the inductor L1 is in a state of change for a long time.
  • Example 2 of the first voltage regulation circuit 402 is a first voltage regulation circuit 402
  • the first voltage regulating circuit 402 may also be a Buck-Boost circuit.
  • the first voltage regulation circuit 402 mainly includes a switch transistor Sa, a switch transistor Sb, a switch transistor Sc, a switch transistor Sd and an adjusting inductor L1.
  • the first end of the switch tube Sa can be used as the connection end 21 of the first voltage regulating circuit, and is connected to the connection end 12 of the LLC resonance conversion unit 401 .
  • the second end of the switch tube Sa may be connected to the first end of the switch tube Sb and one end of the adjusting inductor L1, respectively.
  • the other end of the adjusting inductance L1 is respectively connected to the second end of the switch Sc and the first end of the switch Sd.
  • the first end of the switch tube Sc can be connected to the output end 13 of the LLC resonant conversion unit 401 as the output end 23 .
  • the second end of the switch Sb and the second end of the switch Sd can be used as the input end 22 and the output end 24 to be grounded.
  • Example 4 of the first voltage regulation circuit 402 is
  • the first voltage regulating circuit 402 may also be a cuk chopper circuit.
  • the first voltage regulation circuit mainly includes a switch tube Sa, a switch tube Sb, an adjustment capacitor C2, an adjustment capacitor C3, an adjustment inductance L1 and an adjustment inductance L2.
  • one end of the adjusting inductance L1 can be used as the input end 21 of the first voltage adjusting circuit, and is connected to the input end 12 of the LLC resonance conversion unit.
  • the other end of the adjusting inductance L1 is respectively connected to the first end of the switch Sa and one end of the adjusting capacitor C2.
  • the other end of the adjusting capacitor C2 is respectively connected to one end of the adjusting inductance L2 and the first end of the switch tube Sb.
  • the other end of the adjusting inductance L2 is connected to one end of the adjusting capacitor C3.
  • the other end of the adjustment capacitor C3, the second end of the switch Sa and the second end of the switch Sb are grounded.
  • the first voltage regulating circuit 402 provided in the foregoing embodiment is a non-isolated conversion circuit with a boosting function or a bucking function.
  • the first voltage regulating circuit 402 may also be an isolated type with a boosting function Or the conversion circuit of the step-down function.
  • the first voltage regulating circuit 402 may be, but is not limited to, a flyback converter, a forward converter, a half-bridge converter, a full-bridge converter, a push-pull converter, a resonant switching converter, etc. type converter.
  • the above example shows possible implementations of the LLC resonant conversion unit 401 and the first voltage regulation circuit 402 in the DC converter.
  • using the DC converter 400 provided by the embodiments of the present application is beneficial to improve the efficiency of the DC converter.
  • the resonance conversion unit at this time can be a combination of N resonance conversion circuits. Among them, N ⁇ 2.
  • each of the N LLC resonant conversion circuits has a plurality of voltage conversion gears.
  • the input terminals of the N LLC resonant conversion circuits form the input terminal 11 and the input terminal 12 in series
  • the output terminals of the K LLC resonant conversion circuits form the output terminal 13 and the output terminal in parallel. end 14.
  • each LLC resonant conversion circuit may be the same as the circuit structure shown in FIG. 9 or FIG. 23 , and the working principle thereof will not be described repeatedly in this application.
  • the DC converter provided by the embodiment of the present application further includes: a plurality of third switch transistors S3, a plurality of fourth switch transistors S4, and a plurality of fifth switch transistors S5.
  • each of the third switches S3 is connected across the first terminals of the input ends of two adjacent LLC resonant conversion circuits; each of the fourth switches is connected across two adjacent LLCs between the second end points of the input end of the resonant conversion circuit; one end of each of the fifth switch tubes is connected to the second end point of the input end of the first LLC resonant conversion unit in two adjacent LLC resonant conversion circuits, and the fifth The other end of the switch tube is connected to the first end of the input end of the second LLC resonant conversion unit in two adjacent LLC resonant conversion circuits.
  • the switches S3 , S4 and S5 are all connected to the controller 403 , and the adjustment state is realized through the driving signal sent by 403 .
  • the controller 403 can flexibly adjust the switching transistors S3, S4 and S5 according to the target transformation ratio Na of the DC converter, thereby adjusting the LLC resonant conversion unit 401 transformation ratio.
  • the DC converter may further include a second voltage regulation voltage 404 .
  • the input terminals of the second voltage regulating circuit 404 are respectively connected in series with the input terminals of the first voltage regulating circuit and the input terminals of the LLC resonant conversion unit to form the first input terminal and the second input terminal.
  • an input end, the output end of the second voltage regulation circuit is respectively connected in parallel with the output end of the first voltage regulation circuit and the output end of the LLC resonant conversion circuit to form the first output end and the second output end .
  • the second voltage regulating circuit may be an LLC resonant conversion circuit or other conversion circuits with high efficiency, for increasing the transformation ratio range of the DC converter.
  • the LLC resonant conversion circuit in the DC converter is connected in series with the input side of the first voltage regulator circuit, and the output side is connected in parallel.
  • the input side of the LLC resonant conversion circuit and the first voltage regulating circuit can also be connected in parallel, and the output side can be connected in series.
  • the input terminal 11 of the LLC resonant circuit can be used as the output terminal 11
  • the output terminal 13 of the LLC resonant conversion unit can be used as the input terminal 13
  • the output terminal 14 of the LLC resonant conversion unit can be used as the input terminal.
  • the output terminal 23 of the first voltage regulating circuit can be used as the input terminal 23
  • the output terminal 24 of the first voltage regulating circuit can be used as the input terminal 24 .
  • the input side (input terminal 13 and input terminal 14 ) of the LLC resonant conversion unit and the input side (input terminal 23 and input terminal 24 ) of the first voltage regulating circuit are connected in parallel, and the output side (output terminal 24 ) of the LLC resonant conversion unit 401 is connected in parallel. terminals 11 and 12) and the output side (output terminals 21 and 22) of the first voltage regulating circuit 402 are connected in series.
  • the input terminal 13 and the input terminal 14 of the LLC resonance conversion unit may receive the input voltage Vi, and the output terminal 11 and the output terminal 12 of the LLC resonance conversion unit 401 may output the output voltage Vo1 of the LLC resonance conversion unit.
  • the input terminal 23 and the input terminal 24 of the first voltage regulating circuit 402 can receive the input voltage Vi of the DC converter, and the output terminal 21 and the output terminal 22 of the first voltage regulating circuit can output the output voltage Vo2 of the first voltage regulating circuit.
  • the DC converter when the input side of the DC converter is connected in parallel and the output side is connected in series, the DC converter is a boost circuit.
  • the LLC resonant conversion unit and the first voltage regulating circuit can also use any of the above examples provided by the embodiment of the present application, and details are not repeated here. .
  • Vo1 of the LLC resonant conversion unit is greater than the second output voltage Vo2.
  • the specific analysis is the same as that of the DC converter shown in FIG. 4 , and will not be repeated here.
  • the structures of the LLC resonant conversion unit and the first voltage regulating circuit may refer to the foregoing embodiments, which will not be described in detail in this application.
  • the DC converter may further include a controller, and the controller may be used to control the LLC resonant conversion unit to convert the input voltage of the DC converter into the first output voltage, and control the voltage regulating circuit to convert the DC to DC The input voltage of the converter is converted into a second output voltage; and the voltage conversion gear of the LLC resonant conversion unit is adjusted.
  • the embodiments of the present application also provide a conversion system.
  • the conversion system may include the aforementioned DC converter and controller.
  • the DC converter includes an LLC resonant conversion unit and a first voltage regulation circuit
  • the LLC resonant conversion unit has a plurality of voltage conversion gears
  • the LLC resonant conversion unit includes a first input end, a second input end, A first output end and a second output end
  • the first voltage regulating circuit includes a second input end, a third input end, a third output end and a fourth output end.
  • the LLC resonance conversion unit includes an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
  • the second input terminal is connected to the third input terminal
  • the first output terminal is connected to the third output terminal
  • the second output terminal is connected to the fourth output terminal.
  • the controller is respectively connected to the LLC resonant conversion unit and the first voltage regulation circuit, and the controller is configured to: control the LLC resonant conversion unit to pass the first input terminal and the first voltage regulator circuit.
  • the first input voltage received by the two input terminals is converted into the output voltage of the conversion system, and the output voltage of the DC converter is output through the first output terminal and the second output terminal; controlling the first output terminal
  • the voltage regulating circuit converts the second input voltage received through the third input terminal and the fourth input terminal into the output voltage of the conversion system, and passes the third output terminal and the fourth output terminal
  • the output voltage of the DC converter is output, and the total input voltage of the DC converter includes the first input voltage and the second input voltage.
  • the embodiments of the present application also provide an electronic device, which may include a power supply and the aforementioned DC converter.
  • the DC converter can be connected to the power supply and convert the voltage output by the power supply into the supply voltage of the load.
  • the power source may be, but not limited to, a battery or a vehicle power source.
  • the electronic device may be a switching power supply, which is connected to the battery and to the load, respectively.
  • the switching power supply can receive the battery voltage provided by the battery, convert the battery voltage into the working voltage of the load, and output it to the load.
  • the electronic device can be a car charger, and the electronic device can be connected to the electrical device.
  • the DC converter can receive the voltage provided by the vehicle power supply, convert the voltage output by the vehicle power supply into the power supply voltage of the electrical equipment, and output it to the electrical equipment.

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Abstract

A direct current converter (400), an electronic device, and a control method for the direct current converter (400), which are used to improve the efficiency of the direct current converter (400). The method comprises: calculating a target variable ratio (S601), the target variable ratio being the variable ratio between the input voltage of a direct current converter (400) and a target output voltage of the direct current converter (400); according to the target variable ratio and the minimum variable ratio of a first voltage regulation circuit (402), determining a first variable ratio of an LLC resonant conversion unit (401) from among a plurality of voltage conversion gears of the LLC resonant conversion unit (401) (S602); and according to the first variable ratio and the target variable ratio, determining a second variable ratio of the first voltage regulation circuit (402) (S603).

Description

一种直流转换器、电子设备及该直流转换器的控制方法A DC converter, electronic equipment and control method of the DC converter
相关申请的交叉引用CROSS-REFERENCE TO RELATED APPLICATIONS
本申请要求在2020年12月31日提交中国专利局、申请号为202011627553.1、申请名称为“一种直流转换器、电子设备及该直流转换器的控制方法”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。This application claims the priority of the Chinese patent application filed on December 31, 2020, with the application number of 202011627553.1 and the application title of "A DC Converter, Electronic Equipment and Control Method of the DC Converter", which The entire contents of this application are incorporated by reference.
技术领域technical field
本申请涉及电路技术领域，尤指一种直流转换器、电子设备及该直流转换器的控制方法。The present application relates to the field of circuit technology, and in particular, to a DC converter, an electronic device and a control method of the DC converter.
背景技术Background technique
LLC谐振转换电路是一种常见的直流-直流电压转换电路，以其可以实现开关管软开关被用于多种类型的电力***内的电压转换器中。例如，电动/混合动力汽车的电源管理***、光伏发电***、通信电源供电***、数据中心等电力***内的电压转换器，常需要使用LLC谐振转换电路实现电压转换。The LLC resonant conversion circuit is a common DC-DC voltage conversion circuit, which can realize the soft switching of switch tubes and is used in voltage converters in various types of power systems. For example, voltage converters in power systems such as power management systems for electric/hybrid vehicles, photovoltaic power generation systems, communication power supply systems, and data centers often need to use LLC resonant conversion circuits to achieve voltage conversion.
一般来说，LLC谐振转换电路中主要包括：逆变电路、谐振电路、变压器和整流电路，逆变器电路用于将输入端接收的直流电压转换为交流电并输出给谐振电路，谐振电路用于实现逆变电路软开关，变压器用于将谐振电路输出的交流电输出给整流电路，整流电路用于将变压器输出的交流电转换为直流电并输出。Generally speaking, the LLC resonant conversion circuit mainly includes: an inverter circuit, a resonant circuit, a transformer and a rectifier circuit. The inverter circuit is used to convert the DC voltage received at the input end into AC power and output it to the resonant circuit. The resonant circuit is used for To realize the soft switching of the inverter circuit, the transformer is used to output the alternating current output by the resonant circuit to the rectifier circuit, and the rectifier circuit is used to convert the alternating current output by the transformer into direct current and output it.
实际使用时，根据负载调压需求，电压转换器的输入电压可以在一定范围内波动、且电压转换器的电压转换比可调。LLC谐振转换电路为了实现逆变电路中的开关管软开关和来提高转换效率，逆变电路开关管的导通时序固定，且开关管的开关频率与谐振电路的谐振频率一致，因此，LLC谐振转换电路的电压转化电路的电压转换比固定，导致LLC谐振转换电路难以满足电压转换器的电压转换需求。In actual use, the input voltage of the voltage converter can fluctuate within a certain range, and the voltage conversion ratio of the voltage converter can be adjusted according to the load voltage regulation requirements. LLC resonant conversion circuit In order to realize the soft switching sum of the switches in the inverter circuit to improve the conversion efficiency, the turn-on sequence of the switches of the inverter circuit is fixed, and the switching frequency of the switches is consistent with the resonant frequency of the resonant circuit. Therefore, the LLC resonance The voltage conversion ratio of the voltage conversion circuit of the conversion circuit is fixed, which makes it difficult for the LLC resonant conversion circuit to meet the voltage conversion requirements of the voltage converter.
为了满足电压转换器的电压转换需求，现有提出了两级转换器架构来满足电压转换器的需求。如图1所示，LLC谐振转换电路将电压转换器输入端接收的电压进行转换并输出，再通过调压电路将LLC谐振转换电路输出的直流电压进行调压，输出满足电压转换器需求的电压。In order to meet the voltage conversion requirements of the voltage converter, a two-stage converter architecture has been proposed to meet the requirements of the voltage converter. As shown in Figure 1, the LLC resonant conversion circuit converts and outputs the voltage received at the input end of the voltage converter, and then regulates the DC voltage output by the LLC resonant conversion circuit through the voltage regulator circuit to output a voltage that meets the requirements of the voltage converter .
但是上述方案在实施时，两级串联连接的架构总体效率等于两级效率相乘，由于调压电路的转换效率较低，将直接降低了直流转换器的转换效率。为了解决这一问题，提出了一种准并联变换的两级转换器架构，如图2所示，LLC谐振转换电路的输入端接收大部分的输入电压，并将接收电压转换为电压转换器需求的电压，调压电路的输入端接收小部分的输入电压，并将接收的电压转换为电压转换器需求的电压。However, when the above solution is implemented, the overall efficiency of the two-stage series-connected architecture is equal to the multiplication of the two-stage efficiency. Since the conversion efficiency of the voltage regulator circuit is low, the conversion efficiency of the DC converter will be directly reduced. To solve this problem, a two-stage converter architecture with quasi-parallel conversion is proposed. As shown in Figure 2, the input terminal of the LLC resonant conversion circuit receives most of the input voltage and converts the received voltage into the voltage converter demand. The input terminal of the voltage regulation circuit receives a small part of the input voltage and converts the received voltage into the voltage required by the voltage converter.
具体实现时，电压转换器的总效率为两个电路转换效率与输入电压占比的加权平均，当电压转换器的输入电压增大，或者电压转换器的输出电压降低时，由于LLC谐振转换电路的电压转换比固定，只能增加调压电路输入端接收的电压来实现，直接降低了电压转换器的转换效率。In specific implementation, the total efficiency of the voltage converter is the weighted average of the conversion efficiency of the two circuits and the ratio of the input voltage. When the input voltage of the voltage converter increases, or the output voltage of the voltage converter decreases, due to the LLC resonant conversion circuit The voltage conversion ratio is fixed, which can only be achieved by increasing the voltage received at the input end of the voltage regulator circuit, which directly reduces the conversion efficiency of the voltage converter.
发明内容SUMMARY OF THE INVENTION
本申请提供了一种直流转换器、电子设备及该直流转换器的控制方法，用于提升直流转换器的转换效率。The present application provides a DC converter, an electronic device and a control method of the DC converter, which are used to improve the conversion efficiency of the DC converter.
第一方面，本申请提供的一种直流转换器的控制方法，该控制方法应用于直流转换器中。其中，直流转换器包括LLC谐振转换单元和第一调压电路，LLC谐振转换单元具有多个电压转换档位，LLC谐振转换单元包括第一输入端、第二输入端、第一输出端和第二输出端，第一调压电路包括第三输入端、第四输入端、第三输出端和第四输出端，第二输入端与第三输入端连接。第一输出端与第三输出端连接，第二输出端与第四输出端。具体地，该控制方法主要包括以下步骤：In a first aspect, the present application provides a control method for a DC converter, and the control method is applied to a DC converter. The DC converter includes an LLC resonant conversion unit and a first voltage regulating circuit, the LLC resonant conversion unit has multiple voltage conversion gears, and the LLC resonant conversion unit includes a first input end, a second input end, a first output end and a first Two output terminals, the first voltage regulating circuit includes a third input terminal, a fourth input terminal, a third output terminal and a fourth output terminal, and the second input terminal is connected to the third input terminal. The first output terminal is connected to the third output terminal, and the second output terminal is connected to the fourth output terminal. Specifically, the control method mainly includes the following steps:
计算目标变比，目标变比为直流转换器输入电压与直流转换器的输出电压之间的变比；根据目标变比与第一调压电压的最小变比，从LLC谐振转换单元的多个电压转换档位中确定LLC谐振转换单元的第一变比；根据目标变比和第一变比确定第一调压电路的第二变比。Calculate the target transformation ratio, the target transformation ratio is the transformation ratio between the input voltage of the DC converter and the output voltage of the DC converter; The first transformation ratio of the LLC resonance conversion unit is determined in the voltage conversion gear; the second transformation ratio of the first voltage regulating circuit is determined according to the target transformation ratio and the first transformation ratio.
采用上述方法，LLC谐振转换单元和第一调压电路的输入端串联，输出端并联，两个转换器件分别转换一部分输入电压，由于LLC谐振转换单元的转换效率大于第一调压电路的转换效率，在确定直流转换器的目标转换比以及第一调压电路的最小变比的情况下，可以尽可能增加LLC谐振转换电路的第一变比，由于LLC谐振转换电路的输入电压固定，第一变比越大，则LLC的输入端可以接收更多的输入电压以及传输更多的功率，保证了整个直流转换器的转换效率。Using the above method, the LLC resonant conversion unit and the input terminal of the first voltage regulating circuit are connected in series, and the output terminal is connected in parallel, and the two conversion devices respectively convert a part of the input voltage. Since the conversion efficiency of the LLC resonant conversion unit is greater than that of the first voltage regulating circuit , when the target conversion ratio of the DC converter and the minimum transformation ratio of the first voltage regulator circuit are determined, the first transformation ratio of the LLC resonant conversion circuit can be increased as much as possible. Since the input voltage of the LLC resonant conversion circuit is fixed, the first The larger the transformation ratio, the more the input voltage of the LLC can be received and the more power can be transmitted, which ensures the conversion efficiency of the entire DC converter.
在一种可能的设计中，根据目标变比与调压电路的最小变比，确定LLC谐振转换单元的第一变比时，根据目标变比与第一调压电压的最小变比，确定LLC谐振转换电路的电压转换档位的取值范围；将LLC谐振转换电路的电压转换档位的取值范围内最大的电压转换档位确定为第一变比。In a possible design, when the first transformation ratio of the LLC resonant conversion unit is determined according to the target transformation ratio and the minimum transformation ratio of the voltage regulation circuit, the LLC is determined according to the minimum transformation ratio of the target transformation ratio and the first voltage regulation voltage. The value range of the voltage conversion gear of the resonance conversion circuit; the largest voltage conversion gear within the value range of the voltage conversion gear of the LLC resonant conversion circuit is determined as the first transformation ratio.
采用上述方法，由于LLC谐振转换单元的效率较高，进一步提高开关电源的效率，可以根据调压电路的最小变比，找到LLC谐振转换单元可实现的最大变比，并将该最大变比作为LLC谐振转换的第一变比，实现LLC谐振转换单元传输更多的功率。With the above method, since the efficiency of the LLC resonant conversion unit is high, the efficiency of the switching power supply is further improved, and the maximum conversion ratio that can be achieved by the LLC resonant conversion unit can be found according to the minimum conversion ratio of the voltage regulator circuit, and the maximum conversion ratio can be used as The first transformation ratio of LLC resonant conversion enables the LLC resonant conversion unit to transmit more power.
在一种可能的实现方式中，利用目标变比和第一变比，确定第二变比，包括：计算LLC谐振转换电路处于第一变比时LLC谐振转换单元的目标输入电压；计算直流转换器输入电压与目标输入电压的第一电压差；将第一电压差与直流转换器的输出电压之间的变比确定为第二变比。In a possible implementation manner, using the target transformation ratio and the first transformation ratio to determine the second transformation ratio includes: calculating the target input voltage of the LLC resonance conversion unit when the LLC resonance conversion circuit is in the first transformation ratio; calculating the DC conversion The first voltage difference between the input voltage of the converter and the target input voltage is determined; the transformation ratio between the first voltage difference and the output voltage of the DC converter is determined as the second transformation ratio.
采用上述方法，在确定LLC谐振转换单元的可实现的最大变比来实现LLC谐振转换单元传输更多的功率的情况下，利用第一调压电路传输当LLC谐振转换单元在最大变比下与总输入电压的差值电压，实现电压的微调。Using the above method, in the case of determining the achievable maximum transformation ratio of the LLC resonant conversion unit to realize that the LLC resonant conversion unit transmits more power, the first voltage regulating circuit is used to transmit when the LLC resonant conversion unit is at the maximum transformation ratio with The difference voltage of the total input voltage realizes the fine-tuning of the voltage.
具体地，控制LLC谐振转换单元处于第一变比，以及控制第一调压电路处于第二变比。Specifically, the LLC resonant conversion unit is controlled to be at the first transformation ratio, and the first voltage regulating circuit is controlled to be at the second transformation ratio.
在一种可能的实现方式中，LLC谐振转换单元包括：逆变电路、谐振电路、变压器和整流电路，控制LLC谐振转换单元处于第一变比，包括：In a possible implementation manner, the LLC resonance conversion unit includes: an inverter circuit, a resonance circuit, a transformer and a rectifier circuit, and the LLC resonance conversion unit is controlled to be in a first transformation ratio, including:
向逆变电路发送驱动信号，控制LLC谐振转换单元处于第一变比。其中，逆变电路接收驱动信号后，逆变电路输出的交流电压的周期与谐振电路的谐振周期相同。A drive signal is sent to the inverter circuit to control the LLC resonance conversion unit to be in the first transformation ratio. Wherein, after the inverter circuit receives the driving signal, the cycle of the AC voltage output by the inverter circuit is the same as the resonant cycle of the resonant circuit.
采用上述方案，由于LLC谐振转换单元中的逆变电路输出的交流电的周期与谐振电路的谐振周期一致才能提升LLC谐振转换单元的效率，为了实现LLC谐振转换单元的可调变比，可以在逆变电路输出的交流电的周期与谐振电路的谐振周期一致的情况下，通过改 变驱动信号改变开关管的导通时序，来实现扩展LLC谐振转换单元的变比范围。With the above solution, the efficiency of the LLC resonant conversion unit can be improved because the cycle of the alternating current output by the inverter circuit in the LLC resonant conversion unit is consistent with the resonant cycle of the resonant circuit. When the cycle of the alternating current output by the variable circuit is consistent with the resonant cycle of the resonant circuit, the on-time sequence of the switch tube is changed by changing the drive signal, so as to expand the transformation ratio range of the LLC resonant conversion unit.
第二方面，本申请实施例提供了一种直流转换器，该直流转换器主要包括LLC谐振转换单元和与第一调压电路。In a second aspect, an embodiment of the present application provides a DC converter, where the DC converter mainly includes an LLC resonant conversion unit and a first voltage regulating circuit.
其中，LLC谐振转换单元包括第一输入端、第二输入端、第一输出端和第二输出端，第一调压电路包括第三输入端、第四输入端、第三输出端和第四输出端。第二输入端与第三输入端连接，第一输出端与第三输出端连接，第二输出端与第四输出端连接。其中，LLC谐振转换单元可以包括逆变电路、谐振电路、变压器和整流电路。The LLC resonant conversion unit includes a first input end, a second input end, a first output end and a second output end, and the first voltage regulating circuit includes a third input end, a fourth input end, a third output end and a fourth output end output. The second input terminal is connected to the third input terminal, the first output terminal is connected to the third output terminal, and the second output terminal is connected to the fourth output terminal. Wherein, the LLC resonance conversion unit may include an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
具体地，逆变电路用于将通过第一输入端和第二输入端接收的第一输入电压转换为交流电压，将该交流电压通谐振电路和变压器传输整流电路，整流电路将变压器输出的交流电压转换为直流转换器的输出电压，并通过第一输出端和第二输出端输出直流转换器的输出电压；LLC谐振转换单元具有多个电压转换档位；第一调压电路用于将通过第三输入端和第四输入端接收到的第二输入电压转换为直流转换器的输出电压，并通过第三输出端和第四输出端输出直流转换器的输出电压，转换电路的总输入电压包括第一输入电压和第二输入电压。Specifically, the inverter circuit is used to convert the first input voltage received through the first input terminal and the second input terminal into an AC voltage, and the AC voltage is transmitted through the resonant circuit and the transformer to a rectifier circuit, and the rectifier circuit converts the AC voltage output by the transformer. The voltage is converted into the output voltage of the DC converter, and the output voltage of the DC converter is output through the first output terminal and the second output terminal; the LLC resonance conversion unit has a plurality of voltage conversion gears; the first voltage regulation circuit is used to The second input voltage received by the third input terminal and the fourth input terminal is converted into the output voltage of the DC converter, and the output voltage of the DC converter is output through the third output terminal and the fourth output terminal, and the total input voltage of the conversion circuit is Including a first input voltage and a second input voltage.
在上述直流转换器结构中，LLC谐振转换单元和第一调压电路的输入侧串联，输出侧并联。假设LLC谐振转换单元的效率为a％，第一调压电路的效率为b％，由于LLC谐振转换单元的效率高于第一调压电路的效率，本申请实施例所提供的直流转换器的效率可以表示为(a％-b％)*(N1*Vo)/Vi+b％，由于当LLC谐振转换单元的变比越大，则直流转换器的效率越高，通过调整LLC谐振转换单元的电压转换档位实现最大变比，利于提高直流转换器的效率。In the above structure of the DC converter, the LLC resonant conversion unit and the input side of the first voltage regulating circuit are connected in series, and the output side is connected in parallel. Assuming that the efficiency of the LLC resonant conversion unit is a%, and the efficiency of the first voltage regulator circuit is b%, since the efficiency of the LLC resonant conversion unit is higher than that of the first voltage regulator circuit, the DC converter provided by the embodiment of the present application has a Efficiency can be expressed as (a%-b%)*(N1*Vo)/Vi+b%, since when the ratio of the LLC resonant conversion unit is larger, the efficiency of the DC converter will be higher, by adjusting the LLC resonant conversion unit The highest voltage conversion gear is achieved to achieve the maximum transformation ratio, which is beneficial to improve the efficiency of the DC converter.
在一种可能的设计中，LLC谐振转换单元处于多个电压转换档位中的任一电压转换档位时，逆变电路输出的交流电压的周期与谐振电路的谐振周期相同、且LLC谐振转换单元的输出电压大于零。In a possible design, when the LLC resonant conversion unit is in any voltage conversion gear among the multiple voltage conversion gears, the period of the AC voltage output by the inverter circuit is the same as the resonance period of the resonant circuit, and the LLC resonant conversion The output voltage of the cell is greater than zero.
在一种可能的实现方式中，LLC谐振转换单元的电压转换效率大于第一调压电路的电压转换效率，LLC谐振转换单元的电压转换效率为LLC谐振转换单元的输出功率与LLC谐振转换单元的输入功率的比值，第一调压电路的电压转换效率为第一调压电路的输出功率与第一调压电路的输入功率的比值。In a possible implementation manner, the voltage conversion efficiency of the LLC resonant conversion unit is greater than the voltage conversion efficiency of the first voltage regulating circuit, and the voltage conversion efficiency of the LLC resonant conversion unit is the output power of the LLC resonant conversion unit and the LLC resonant conversion unit. The ratio of the input power, the voltage conversion efficiency of the first voltage regulating circuit is the ratio of the output power of the first voltage regulating circuit to the input power of the first voltage regulating circuit.
在一种可能的实现方式中，控制器。In one possible implementation, the controller.
其中，控制器用于控制LLC谐振转换单元将第一输入电压转换为直流转换器的输出电压，控制第一调压电路将第二输入电压转换为直流转换器的输出电压；以及根据直流转换器的目标变比，调整LLC谐振转换单元的电压转换档位。其中，目标变比为总输入电压与直流转换器的目标输出电压之间的比值。The controller is used to control the LLC resonant conversion unit to convert the first input voltage into the output voltage of the DC converter, control the first voltage regulating circuit to convert the second input voltage to the output voltage of the DC converter; The target transformation ratio, adjust the voltage conversion gear of the LLC resonance conversion unit. The target transformation ratio is the ratio between the total input voltage and the target output voltage of the DC converter.
也即，在控制器的控制下实现直流转换器中各电路状态的调整。That is, the adjustment of each circuit state in the DC converter is realized under the control of the controller.
在一种可能的实现方式中，LLC谐振转换单元包括：逆变电路、谐振电路、变压器和整流电路。In a possible implementation manner, the LLC resonance conversion unit includes: an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
其中，逆变电路的两个输入端分别形成第一输入端和第二输入端，逆变电路的一个输出端与谐振电路一端连接，逆变电路的另一个输出端与变压器原边绕组的一端连接；谐振电路另一端与变压器原边绕组的另一端连接；变压器副边绕组的两端分别与整流电路的两个输入端连接；整流电路的两个输出端分别形成第一输出端和第二输出端。The two input ends of the inverter circuit respectively form the first input end and the second input end, one output end of the inverter circuit is connected to one end of the resonant circuit, and the other output end of the inverter circuit is connected to one end of the primary winding of the transformer The other end of the resonant circuit is connected to the other end of the primary winding of the transformer; the two ends of the secondary winding of the transformer are respectively connected to the two input ends of the rectifier circuit; the two output ends of the rectifier circuit respectively form the first output end and the second output.
其中，逆变电路具有多个电压转换比，多个电压转换比与LLC谐振转换单元的多个电 压转换单元的多个电压转换档位一对一。Wherein, the inverter circuit has a plurality of voltage conversion ratios, and the plurality of voltage conversion ratios are one-to-one with the plurality of voltage conversion gears of the plurality of voltage conversion units of the LLC resonance conversion unit.
采用该实现LLC谐振转换电路结构，可以通过调整逆变电路的转换比，实现LLC谐振转换单元的可调变比，从而有利于控制LLC谐振转换单元处于更大的变比，传输更多的功率，进一步提高直流转换器的效率。By adopting the structure of realizing LLC resonant conversion circuit, the adjustable conversion ratio of LLC resonant conversion unit can be realized by adjusting the conversion ratio of the inverter circuit, which is beneficial to control the LLC resonant conversion unit to be in a larger conversion ratio and transmit more power , further improving the efficiency of the DC converter.
具体地，逆变电路至少存在以下可能的实现方式：Specifically, the inverter circuit has at least the following possible implementations:
逆变电路的实现方式一：The first implementation of the inverter circuit:
逆变电路包括：H桥电路和第一电容。The inverter circuit includes: an H bridge circuit and a first capacitor.
其中，H桥电路的第一桥臂的第一端形成第一输入端，第一桥臂的第二端与谐振电路的一端连接，H桥电路的第二桥臂的第一端形成第二输入端，第二桥臂的第一端与谐振电路的形成第二输入端，第二桥臂的第二端与第一桥臂的第二端连接，H桥电路用于接收第一驱动信号，并根据第一驱动信号，调整LLC谐振转换单元的电压转换档位；第一电容跨接在第一桥臂的中间节点和第二桥臂的中间节点之间。The first end of the first bridge arm of the H-bridge circuit forms the first input end, the second end of the first bridge arm is connected to one end of the resonant circuit, and the first end of the second bridge arm of the H-bridge circuit forms the second end The input end, the first end of the second bridge arm forms the second input end of the resonant circuit, the second end of the second bridge arm is connected with the second end of the first bridge arm, and the H bridge circuit is used to receive the first drive signal , and adjust the voltage conversion gear of the LLC resonance conversion unit according to the first driving signal; the first capacitor is connected across the middle node of the first bridge arm and the middle node of the second bridge arm.
采用上述逆变电路结构，可以通过接收的驱动信号控制H桥电路中开关管的导通时序，来控制第一电容进行充放电，实现逆变电路输出不同的电压数值，从而实现调整LLC谐振转换单元的变比。With the above inverter circuit structure, the on-time sequence of the switch tube in the H-bridge circuit can be controlled by the received drive signal, so as to control the charging and discharging of the first capacitor, so that the inverter circuit can output different voltage values, so as to realize the adjustment of LLC resonance conversion. unit ratio.
逆变电路的实现方式二：The second implementation of the inverter circuit:
逆变电路包括：飞跨电容型多电平半桥逆变电路、第一开关管和第二开关管。The inverter circuit includes: a flying capacitor type multi-level half-bridge inverter circuit, a first switch tube and a second switch tube.
其中，飞跨电容型多电平半桥逆变电路的第一输入端形成所述第一输入端，飞跨电容型多电平逆变电路的第二输入端形成所述第二输入端，飞跨电容型多电平半桥逆变电路的第一输出端与第一开关管的第一端连接，飞跨电容型多电平半桥逆变电路的第二输出端与第二开关管的第一端连接，飞跨电容型多电平半桥逆变电路用于接收第二驱动信号，并根据第二驱动信号，调整LLC谐振转换单元的电压转换档位；第一开关管的第二端与谐振电路的一端连接；第二开关管的第二端与第一开关管的第二端连接。Wherein, the first input terminal of the flying capacitor type multilevel half-bridge inverter circuit forms the first input terminal, and the second input terminal of the flying capacitor type multilevel inverter circuit forms the second input terminal, The first output terminal of the flying capacitor type multi-level half-bridge inverter circuit is connected to the first terminal of the first switch tube, and the second output terminal of the flying capacitor type multi-level half-bridge inverter circuit is connected to the second switch tube The first end of the flying capacitor type multi-level half-bridge inverter circuit is used to receive the second driving signal, and according to the second driving signal, adjust the voltage conversion gear of the LLC resonant conversion unit; The two ends are connected to one end of the resonant circuit; the second end of the second switch tube is connected to the second end of the first switch tube.
采用上述逆变电路结构，可以通过接收的驱动信号控制飞跨电容型多电平半桥逆变电路中开关管的导通时序，来控制多个飞跨电容进行充放电，实现逆变电路输出不同的电压数值，从而实现调整LLC谐振转换单元的变比。With the above inverter circuit structure, the on-time sequence of the switching tubes in the flying capacitor type multi-level half-bridge inverter circuit can be controlled by the received driving signal, so as to control the charging and discharging of multiple flying capacitors, so as to realize the output of the inverter circuit. Different voltage values can be used to adjust the transformation ratio of the LLC resonant conversion unit.
在一种可能的设计中，当单个LLC谐振转换单元的变比有限的情况下，为了进一步提升直流转换器的转换效率，LLC谐振转换单元包括N个LLC谐振转换电路。其中，N个LLC谐振转换电路中的每一个LLC谐振转换电路均具有多个电压转换档位。其中，N是大于或等于2的整数。In a possible design, when the transformation ratio of a single LLC resonant conversion unit is limited, in order to further improve the conversion efficiency of the DC converter, the LLC resonant conversion unit includes N LLC resonant conversion circuits. Wherein, each LLC resonant conversion circuit in the N LLC resonant conversion circuits has a plurality of voltage conversion gears. where N is an integer greater than or equal to 2.
其中，N个LLC谐振转换电路的输入端串联形成第一输入端和第二输入端，N个LLC谐振转换电路的输出端并联形成第一输出端和第二输出端。The input terminals of the N LLC resonant conversion circuits are connected in series to form the first input terminal and the second input terminal, and the output terminals of the N LLC resonant conversion circuits are connected in parallel to form the first output terminal and the second output terminal.
在一种可能的设计中，直流转换器还可以包括：多个第三开关管、多个第四开关管和多个第五开关管。In a possible design, the DC converter may further include: a plurality of third switch tubes, a plurality of fourth switch tubes, and a plurality of fifth switch tubes.
其中，每一个第三开关管跨接在相邻两个LLC谐振转换电路的输入端的第一端点之间；每一个第四开关管跨接在相邻两个LLC谐振转换电路的输入端的第二端点之间；每一个第五开关管的一端与相邻两个LLC谐振转换电路中第一个LLC谐振转换单元输入端的第二端点连接，第五开关管的另一端与相邻两个LLC谐振转换电路中第二个LLC谐振转换单元输入端的第一端点连接。其中，第一端点为LLC谐振转换电路接收高电平的一端，第二端点为LLC谐振转换电路接收低电平的一端。Wherein, each third switch is connected across the first terminals of the input ends of two adjacent LLC resonant conversion circuits; each fourth switch is connected across the first end of the input ends of the adjacent two LLC resonant conversion circuits. between two terminals; one end of each fifth switch is connected to the second terminal of the input end of the first LLC resonant conversion unit in two adjacent LLC resonant conversion circuits, and the other end of the fifth switch is connected to two adjacent LLCs The first terminal of the input end of the second LLC resonance conversion unit in the resonance conversion circuit is connected. The first endpoint is the end of the LLC resonant conversion circuit that receives the high level, and the second endpoint is the end of the LLC resonant conversion circuit that receives the low level.
采用上述直流转换器结构，在输入电压和输出电压的电压发生变化，导致直流转换器目标变比发生变化时，可以将多个LLC谐振转换电路的输入侧由串联改为并联，从而调整LLC谐振转换单元的变比，即随着应用场景实时调整变比。With the above structure of the DC converter, when the input voltage and the output voltage change, resulting in a change in the target transformation ratio of the DC converter, the input sides of multiple LLC resonant conversion circuits can be changed from series to parallel, so as to adjust the LLC resonance The transformation ratio of the conversion unit, that is, the transformation ratio is adjusted in real time with the application scenario.
在一种可能设计中，当LLC谐振转换单元的最大变比远小于目标变比时，为了提升直流转换器的效率，直流转换器还包括：转换效率较高的第二调压电路。In a possible design, when the maximum transformation ratio of the LLC resonant conversion unit is much smaller than the target transformation ratio, in order to improve the efficiency of the DC converter, the DC converter further includes: a second voltage regulating circuit with higher conversion efficiency.
其中，第二调压电路的输入端分别与第一调压电路的输入端和LLC谐振转换单元的输入端串联形成第一输入端和第二输入端，第二调压电路的输出端分别与第一调压电路的输出端和LLC谐振转换电路的输出端并联形成第一输出端和所述第二输出端。Wherein, the input end of the second voltage regulating circuit is connected in series with the input end of the first voltage regulating circuit and the input end of the LLC resonant conversion unit respectively to form the first input end and the second input end, and the output end of the second voltage regulating circuit is respectively connected with the input end of the LLC resonant conversion unit. The output end of the first voltage regulating circuit and the output end of the LLC resonant conversion circuit are connected in parallel to form the first output end and the second output end.
在一种可能的设计中，第一调压电路可以是Buck电路。In one possible design, the first voltage regulation circuit may be a Buck circuit.
第三方面，本申请实施例提供了一种直流转换器，该直流转换器主要包括LLC谐振转换单元和与第一调压电路。In a third aspect, an embodiment of the present application provides a DC converter, where the DC converter mainly includes an LLC resonant conversion unit and a first voltage regulating circuit.
其中，LLC谐振转换单元包括第一输入端、第二输入端、第一输出端和第二输出端。第一调压电路包括第三输入端、第四输入端、第三输入端和第四输出端。其中，LLC谐振转换单元包括逆变电路、谐振电路、变压器和整流电路。Wherein, the LLC resonance conversion unit includes a first input end, a second input end, a first output end and a second output end. The first voltage regulating circuit includes a third input terminal, a fourth input terminal, a third input terminal and a fourth output terminal. Wherein, the LLC resonance conversion unit includes an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
具体地，第二输出端和第三输出端连接，第一输入端与第三输入端连接，第二输入端与第四输入端连接。Specifically, the second output terminal is connected to the third output terminal, the first input terminal is connected to the third input terminal, and the second input terminal is connected to the fourth input terminal.
其中，逆变电路可以用于将通过第一输入端和第二输入端接收的直流转换器输入电压转换为交流电压，并交流电压通过谐振电路和变压器传输能给整流电路，整流电路将变压器输出的交流电压转换为第一输出电压，并通过第一输出端和第二输出端输出；LLC谐振转换单元具有多个电压转换档位；第一调压电路用于将通过第三输入端和第四输入端接收的直流转换器输入电压转换为第二输出电压，并通过第三输入端和第四输出端输出，直流转换器的总输出电压包括第一输出电压和第二输出电压。The inverter circuit can be used to convert the input voltage of the DC converter received through the first input terminal and the second input terminal into an AC voltage, and the AC voltage can be transmitted to the rectifier circuit through the resonant circuit and the transformer, and the rectifier circuit outputs the output of the transformer. The AC voltage is converted into the first output voltage and output through the first output terminal and the second output terminal; the LLC resonant conversion unit has multiple voltage conversion gears; the first voltage regulating circuit is used to The input voltage of the DC converter received by the four input terminals is converted into a second output voltage and output through the third input terminal and the fourth output terminal. The total output voltage of the DC converter includes the first output voltage and the second output voltage.
采用上述直流转换器结构，LLC谐振转换单元和第一调压电路的输入侧并联，输出侧串联，主要用于升压应用场景中、且具有与第二方面类似的技术效果，第三方面中相应方案的技术效果可以参照第二方面中对应方案可以得到的技术效果，重复之处不予详述。Using the above DC converter structure, the LLC resonant conversion unit is connected in parallel with the input side of the first voltage regulator circuit, and the output side is connected in series, which is mainly used in boost application scenarios, and has similar technical effects as the second aspect. In the third aspect For the technical effect of the corresponding solution, reference may be made to the technical effect that can be obtained by the corresponding solution in the second aspect, and the repeated parts will not be described in detail.
在一种可能的设计中，LLC谐振转换单元处于多个电压转换档位中的任一电压转换档位时，逆变电路输出的交流电压的周期与谐振电路的谐振周期相同、且LLC谐振转换单元的输出电压大于零。In a possible design, when the LLC resonant conversion unit is in any voltage conversion gear among the multiple voltage conversion gears, the period of the AC voltage output by the inverter circuit is the same as the resonance period of the resonant circuit, and the LLC resonant conversion The output voltage of the cell is greater than zero.
在一种可能的设计中，LLC谐振转换单元的电压转换效率大于调压电路的电压转换效率，LLC谐振转换单元的电压转换效率为LLC谐振转换单元的输出功率与LLC谐振转换单元的输入功率的比值，调压电路的电压转换效率为调压电路的输出功率与调压电路的输入功率的比值。In a possible design, the voltage conversion efficiency of the LLC resonant conversion unit is greater than that of the voltage regulator circuit, and the voltage conversion efficiency of the LLC resonant conversion unit is the difference between the output power of the LLC resonant conversion unit and the input power of the LLC resonant conversion unit The voltage conversion efficiency of the voltage regulator circuit is the ratio of the output power of the voltage regulator circuit to the input power of the voltage regulator circuit.
在一种可能的设计中，直流转换器还包括：控制器。In one possible design, the DC converter further includes: a controller.
其中，控制器用于控制LLC谐振转换单元将直流转换器的输入电压转换为第一输出电压，控制调压电路将直流转换器的输入电压转换为第二输出电压；以及根据直流转换器的目标变比，调整LLC谐振转换单元的电压转换档位。其中，目标变比为输入电压与目标输出电压的比值。The controller is used to control the LLC resonant conversion unit to convert the input voltage of the DC converter into the first output voltage, and control the voltage regulating circuit to convert the input voltage of the DC converter to the second output voltage; ratio, adjust the voltage conversion gear of the LLC resonant conversion unit. The target transformation ratio is the ratio of the input voltage to the target output voltage.
第四方面，本申请实施例提供了一种转换***，该转换***主要包括直流转换器和控制器。In a fourth aspect, an embodiment of the present application provides a conversion system, where the conversion system mainly includes a DC converter and a controller.
具体地，直流转换器主要包括LLC谐振转换单元和第一调压电路，LLC谐振转换单 元具有多个电压转换档位，LLC谐振转换单元包括第一输入端、第二输入端、第一输出端和第二输出端，第一调压电路包括第二输入端、第三输入端、第三输出端和第四输出端。其中，LLC谐振转换单元包括逆变电路、谐振电路、变压器和整流电路。Specifically, the DC converter mainly includes an LLC resonant conversion unit and a first voltage regulation circuit, the LLC resonant conversion unit has multiple voltage conversion gears, and the LLC resonant conversion unit includes a first input end, a second input end, and a first output end and a second output terminal, the first voltage regulating circuit includes a second input terminal, a third input terminal, a third output terminal and a fourth output terminal. Wherein, the LLC resonance conversion unit includes an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
具体地，第二输入端与第三输入端连接，第一输出端与第三输出端连接，第二输出端与第四输出端连接。Specifically, the second input terminal is connected to the third input terminal, the first output terminal is connected to the third output terminal, and the second output terminal is connected to the fourth output terminal.
其中，控制器分别与LLC谐振转换单元和第一调压电路连接，控制器可以用于：控制逆变电路将通过第一输入端和第二输入端接收到的第一输入电压转换为交流电压，将该交流电压通过谐振电路和变压器传输给整流电路，整流电路将变压器输出的交流电压转换***的输出电压，并通过第一输出端和第二输出端输出直流转换器的输出电压；控制第一调压电路将通过第三输入端和第四输入端接收到的第二输入电压转换为转换***的输出电压，并通过第三输出端和第四输出端输出直流转换器的输出电压，直流转换器的总输入电压包括第一输入电压和第二输入电压。The controller is respectively connected with the LLC resonance conversion unit and the first voltage regulating circuit, and the controller can be used for: controlling the inverter circuit to convert the first input voltage received through the first input terminal and the second input terminal into an AC voltage , the AC voltage is transmitted to the rectifier circuit through the resonant circuit and the transformer, and the rectifier circuit converts the AC voltage output by the transformer to the output voltage of the system, and outputs the output voltage of the DC converter through the first output terminal and the second output terminal; A voltage regulating circuit converts the second input voltage received through the third input terminal and the fourth input terminal into the output voltage of the conversion system, and outputs the output voltage of the DC converter through the third output terminal and the fourth output terminal, the DC The total input voltage of the converter includes a first input voltage and a second input voltage.
采用上述转换***结构，可以通过控制器从多个电压转换档位中为LLC谐振转换单元配置合适的最大变比，使LLC谐振转换单元传输更多的功率，由于LLC谐振转换单元的效率大于调压电路的效率，有利于提升转换***的效率。With the above conversion system structure, the LLC resonant conversion unit can be configured with a suitable maximum transformation ratio from multiple voltage conversion gears through the controller, so that the LLC resonant conversion unit can transmit more power. The efficiency of the voltage circuit is beneficial to improve the efficiency of the conversion system.
第五方面，本申请实施例提供了一种电子设备，该电子设备可以包括电源和前述实施例提供的直流转换器。In a fifth aspect, the embodiments of the present application provide an electronic device, and the electronic device may include a power supply and the DC converter provided in the foregoing embodiments.
其中，直流转换器可以与电源连接，该直流转换器可以将电源输出的电压转换为负载的供电电压。Wherein, the DC converter can be connected with the power supply, and the DC converter can convert the voltage output by the power supply into the supply voltage of the load.
可选地，该电子设备可以开关电源。Optionally, the electronic device can be powered on and off.
可选地，该电子设备可以是车载充电器。Optionally, the electronic device may be an on-board charger.
采用上述电子设备，可以通过前述直流转换器提升电子设备的效率。With the above-mentioned electronic device, the efficiency of the electronic device can be improved by the aforementioned DC converter.
本申请的这些方面或其它方面在以下实施例的描述中会更加简明易懂。These and other aspects of the present application will be more clearly understood in the description of the following embodiments.
附图说明Description of drawings
图1为一种两级转换器架构结构示意图一；FIG. 1 is a schematic diagram 1 of a two-stage converter architecture structure;
图2为一种两级转换器架构结构示意图二；FIG. 2 is a schematic diagram 2 of a two-stage converter architecture structure;
图3为一种LLC谐振转换单元的结构示意图；3 is a schematic structural diagram of an LLC resonant conversion unit;
图4为本申请实施例提供的一种直流转换器结构示意图一；FIG. 4 is a schematic structural diagram 1 of a DC converter provided by an embodiment of the present application;
图5为本申请实施例提供的一种直流转换器结构示意图二；FIG. 5 is a second structural schematic diagram of a DC converter provided by an embodiment of the present application;
图6为本申请实施例提供的一种调节直流转换器的变比的方法流程示意图；6 is a schematic flowchart of a method for adjusting the transformation ratio of a DC converter provided by an embodiment of the present application;
图7为本申请实施例提供的一种具体的调节直流转换器的变比的方法流程示意图；7 is a schematic flowchart of a specific method for adjusting the transformation ratio of a DC converter provided by an embodiment of the present application;
图8为本申请实施例提供的一种变比变化确定过程示意图；8 is a schematic diagram of a process for determining a variable ratio change provided by an embodiment of the present application;
图9为本申请实施例提供的一种LLC谐振转换单元的结构示意图；9 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the present application;
图10为本申请实施例提供的一种驱动信号示意图；FIG. 10 is a schematic diagram of a driving signal provided by an embodiment of the present application;
图11为本申请实施例提供的一种LLC谐振转换单元开关状态示意图；11 is a schematic diagram of a switching state of an LLC resonant conversion unit provided by an embodiment of the application;
图12为本申请实施例提供的一种LLC谐振转换单元的等效电路示意图；12 is a schematic diagram of an equivalent circuit of an LLC resonant conversion unit provided by an embodiment of the application;
图13为本申请实施例提供的一种LLC谐振转换单元的开关状态示意图；13 is a schematic diagram of a switching state of an LLC resonant conversion unit provided by an embodiment of the application;
图14为本申请实施例提供的一种LLC谐振转换单元的等效电路示意图；14 is a schematic diagram of an equivalent circuit of an LLC resonant conversion unit provided by an embodiment of the application;
图15为本申请实施例提供的一种LLC谐振转换单元的开关状态示意图；15 is a schematic diagram of a switching state of an LLC resonant conversion unit provided by an embodiment of the application;
图16为本申请实施例提供的一种LLC谐振转换单元的等效电路示意图；16 is a schematic diagram of an equivalent circuit of an LLC resonant conversion unit provided by an embodiment of the application;
图17为本申请实施例提供的一种驱动信号示意图；FIG. 17 is a schematic diagram of a driving signal provided by an embodiment of the present application;
图18为本申请实施例提供的一种LLC谐振转换单元的开关状态示意图；18 is a schematic diagram of a switching state of an LLC resonant conversion unit provided by an embodiment of the application;
图19为本申请实施例提供的一种LLC谐振转换单元的等效电路示意图；19 is a schematic diagram of an equivalent circuit of an LLC resonant conversion unit provided by an embodiment of the application;
图20为本申请实施例提供的一种LLC谐振转换单元的结构示意图；20 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application;
图21为本申请实施例提供的一种LLC谐振转换单元的结构示意图；21 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application;
图22为本申请实施例提供的一种LLC谐振转换单元的结构示意图；22 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application;
图23为本申请实施例提供的一种LLC谐振转换单元的结构示意图；23 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application;
图24为本申请实施例提供的一种驱动信号示意图；FIG. 24 is a schematic diagram of a driving signal provided by an embodiment of the application;
图25为本申请实施例提供的一种LLC谐振转换单元的结构示意图；25 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application;
图26为本申请实施例提供的一种第一调压电路的结构示意图；FIG. 26 is a schematic structural diagram of a first voltage regulation circuit provided by an embodiment of the application;
图27为本申请实施例提供的一种第一调压电路的结构示意图；FIG. 27 is a schematic structural diagram of a first voltage regulating circuit provided by an embodiment of the application;
图28为本申请实施例提供的一种LLC谐振转换单元的结构示意图；28 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application;
图29为本申请实施例提供的一种LLC谐振转换单元的结构示意图；29 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application;
图30为本申请实施例提供的一种LLC谐振转换单元的结构示意图；30 is a schematic structural diagram of an LLC resonant conversion unit provided by an embodiment of the application;
图31为本申请实施例提供的另一种直流转换器的结构示意图。FIG. 31 is a schematic structural diagram of another DC converter according to an embodiment of the present application.
具体实施方式Detailed ways
为了使本申请的目的、技术方案和优点更加清楚，下面将结合附图对本申请作进一步地详细描述。方法实施例中的具体操作方法也可以应用于装置实施例或***实施例中。需要说明的是，在本申请的描述中“至少一个”是指一个或多个，其中，多个是指两个或两个以上。鉴于此，本发明实施例中也可以将“多个”理解为“至少两个”。“和/或”，描述关联对象的关联关系，表示可以存在三种关系，例如，A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。另外，字符“/”，如无特殊说明，一般表示前后关联对象是一种“或”的关系。另外，需要理解的是，在本申请的描述中，“第一”、“第二”等词汇，仅用于区分描述的目的，而不能理解为指示或暗示相对重要性，也不能理解为指示或暗示顺序。In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings. The specific operation methods in the method embodiments may also be applied to the apparatus embodiments or the system embodiments. It should be noted that, in the description of the present application, "at least one" refers to one or more, wherein a plurality of refers to two or more. In view of this, in the embodiment of the present invention, "a plurality" may also be understood as "at least two". "And/or", which describes the association relationship of the associated objects, means that there can be three kinds of relationships, for example, A and/or B, which can mean that A exists alone, A and B exist at the same time, and B exists alone. In addition, the character "/", unless otherwise specified, generally indicates that the associated objects are an "or" relationship. In addition, it should be understood that in the description of this application, words such as "first" and "second" are only used for the purpose of distinguishing descriptions, and cannot be understood as indicating or implying relative importance, nor can they be understood as indicating or implied order.
需要指出的是，本申请实施例中“连接”指的是电连接，两个电学元件连接可以是两个电学元件之间的直接或间接连接。例如，A与B连接，既可以是A与B直接连接，也可以是A与B之间通过一个或多个其它电学元件间接连接，例如A与B连接，也可以是A与C直接连接，C与B直接连接，A与B之间通过C实现了连接。It should be pointed out that the "connection" in the embodiments of the present application refers to an electrical connection, and the connection of two electrical elements may be a direct or indirect connection between the two electrical elements. For example, the connection between A and B can be either a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components, such as the connection between A and B, or the direct connection between A and C, C and B are directly connected, and A and B are connected through C.
需要指出的是，本申请实施例中转换电路“变比”指的是转换电路的输入电压和输出电压中的较大电压与输入电压和输出电压中的较小电压之间的比值。若转换电路执行降压转换，则转换电路的输出电压小于转换电路的输入电压，转换电路的变比为输入电压/输出电压。若转换电路执行升压转换，则转换电路的输出电压大于转换电路的输入电压，转换电路的变比为输出电压/输入电压。It should be pointed out that the "transformation ratio" of the conversion circuit in the embodiments of the present application refers to the ratio between the larger voltage of the input voltage and the output voltage of the conversion circuit and the smaller voltage of the input voltage and the output voltage. If the conversion circuit performs step-down conversion, the output voltage of the conversion circuit is smaller than the input voltage of the conversion circuit, and the transformation ratio of the conversion circuit is input voltage/output voltage. If the conversion circuit performs boost conversion, the output voltage of the conversion circuit is greater than the input voltage of the conversion circuit, and the conversion ratio of the conversion circuit is output voltage/input voltage.
随着电力电子领域的发展，开关型转换器获得了越来越广泛的应用，相应的，开关型转换器的设计也面临高功率密度，高效率和快速的动态特性等综合性能的要求。为了达到更高的功率密度，通常采用提高开关频率的方法来减小转换器中的电容、电感、变压器等磁性元件的体积，但是开关频率的提高会导致开关损耗的增加，从而降低开关型转换器的 效率。With the development of the power electronics field, switch-mode converters have been widely used. Accordingly, the design of switch-mode converters also faces the requirements of comprehensive performance such as high power density, high efficiency and fast dynamic characteristics. In order to achieve higher power density, the method of increasing the switching frequency is usually used to reduce the volume of magnetic components such as capacitors, inductors, and transformers in the converter. efficiency of the device.
软开关技术是开关型转换器实现高转换效率的重要技术之一。其中，LLC谐振转换器被人们做了大量的研究和广泛的应用。如图3所示，LLC谐振转换器主要包括：逆变电路、谐振电路、变压器和整流电路。其中，逆变电路的第一输出端与谐振电路的一端连接，逆变电路的另一个输出端与变压器原边绕组的一端连接；谐振电路的另一端与变压器原边绕组的另一端连接；变压器副边绕组的两端分别与整流电路的两个输入端连接。Soft switching technology is one of the important technologies for switching converters to achieve high conversion efficiency. Among them, LLC resonant converters have been widely studied and widely used. As shown in Figure 3, the LLC resonant converter mainly includes: an inverter circuit, a resonant circuit, a transformer and a rectifier circuit. The first output end of the inverter circuit is connected to one end of the resonant circuit, the other output end of the inverter circuit is connected to one end of the primary winding of the transformer; the other end of the resonant circuit is connected to the other end of the primary winding of the transformer; the transformer Two ends of the secondary winding are respectively connected with two input ends of the rectifier circuit.
具体工作时，逆变电路中的开关管通常工作在50％占空比的开关频率下，可以通过调整开关管的开关频率控制整个LLC谐振变换器的变比。当在谐振电路的谐振频率下运行时，LLC谐振转换器可以获得软开关和低传导损耗，此时它具有最大的效率。当开关频率越偏离开谐振频率时，LLC谐振转换器效率越低。During specific operation, the switching tube in the inverter circuit usually works at a switching frequency of 50% duty cycle, and the transformation ratio of the entire LLC resonant converter can be controlled by adjusting the switching frequency of the switching tube. The LLC resonant converter can achieve soft switching and low conduction losses when operating at the resonant frequency of the resonant circuit, where it has maximum efficiency. The LLC resonant converter is less efficient as the switching frequency deviates further from the resonant frequency.
具体实现时，为了实现保证LLC谐振转换器的效率，逆变电路中开关管的导通时序和开关频率固定，实现逆变中开关管的开关频率与谐振电路的谐振频率一致，来达到最大的效率，在这种情况下LLC谐振转换电路的变比固定。In the specific implementation, in order to ensure the efficiency of the LLC resonant converter, the conduction sequence and switching frequency of the switch tube in the inverter circuit are fixed, so that the switching frequency of the switch tube in the inverter is consistent with the resonant frequency of the resonant circuit, so as to achieve the maximum efficiency, in this case the ratio of the LLC resonant conversion circuit is fixed.
实际的电源应用中通常需要可调节多种不同的输出电压，且输入电压也可以适应一定的宽范围，转换器需要输出不同的变比来满足电源的运行在不同的变压比，单级LLC谐振转换变换器的变比已经难以满足电源的供电需求，基于此，设置了两级转换器的供电架构。In practical power supply applications, it is usually necessary to adjust a variety of different output voltages, and the input voltage can also adapt to a certain wide range. The converter needs to output different transformation ratios to meet the operation of the power supply at different transformation ratios. Single-stage LLC The transformation ratio of the resonant conversion converter has been difficult to meet the power supply requirements of the power supply. Based on this, the power supply architecture of the two-stage converter is set up.
参见图2所示的两级转换器供电架构示意图。其中，LLC谐振转换器具有固定的电压转换档位，Buck电路用于转换LLC谐振转换器无法转换的电压，实现电压调整。Refer to the schematic diagram of the two-stage converter power supply architecture shown in FIG. 2 . Among them, the LLC resonant converter has a fixed voltage conversion gear, and the Buck circuit is used to convert the voltage that the LLC resonant converter cannot convert to realize voltage adjustment.
例如LLC谐振转换器的效率为97％，Buck电路的效率为88％，LLC谐振转换器的变比为30，图2所示的两级转换器供电架构的输入电压在[40-60]V范围内变动，输出电压在[0.6-1.2]V范围内变动为例。For example, the efficiency of the LLC resonant converter is 97%, the efficiency of the Buck circuit is 88%, the transformation ratio of the LLC resonant converter is 30, and the input voltage of the two-stage converter power supply architecture shown in Figure 2 is [40-60]V For example, the output voltage varies within the range of [0.6-1.2]V.
当两级转换器供电架构下的输入电压为40V、且输出电压为1.2V时，LLC谐振转换器的输入电压为36V，输出电压为1.2V，Buck电路的输入电压为4V，输出电压为1.2V，此时两级转换器供电架构的总效率为36/40*97％+4/40*88％≈96％；当两级转换器供电架构下的输入电压为60V、且输出电压为0.6V时，LLC谐振转换器的输出电压为18V，输出电压为0.6V，Buck电路的输入电压为42V，输出电压为0.6V，此时两级转换器供电架构的总效率为18/60*97％+42/60*88％≈91％。因此，在图2所示转换器结构中，当LLC谐振转换器承受的输入电压与两级转换器供电架构的输入电压的占比越小，转换器的效率越低。When the input voltage of the two-stage converter power supply structure is 40V and the output voltage is 1.2V, the input voltage of the LLC resonant converter is 36V, the output voltage is 1.2V, the input voltage of the Buck circuit is 4V, and the output voltage is 1.2V V, at this time, the total efficiency of the two-level converter power supply architecture is 36/40*97%+4/40*88%≈96%; when the input voltage under the two-level converter power supply architecture is 60V, and the output voltage is 0.6 At V, the output voltage of the LLC resonant converter is 18V, the output voltage is 0.6V, the input voltage of the Buck circuit is 42V, and the output voltage is 0.6V, at this time, the total efficiency of the two-stage converter power supply architecture is 18/60*97 %+42/60*88%≈91%. Therefore, in the converter structure shown in FIG. 2 , when the ratio of the input voltage borne by the LLC resonant converter to the input voltage of the two-stage converter power supply structure is smaller, the efficiency of the converter is lower.
有鉴于此，本申请提供了一种直流转换器，该直流转换器可以应用于开关电源，不仅可以满足开关电源的变比需求，还有利于提高开关电源的效率。In view of this, the present application provides a DC converter, which can be applied to a switching power supply, which can not only meet the transformation ratio requirements of the switching power supply, but also help improve the efficiency of the switching power supply.
如图4所示，本申请实施例所提供的直流转换器400主要包括LLC谐振转换单元401和第一调压电路402。其中，LLC谐振转换单元401包括第一输入端11、第二输入端12、第一输出端13和第二输出端14。第一调压电路402包括第三输入端21、第四输入端22、第三输出端23和第四输出端24。As shown in FIG. 4 , the DC converter 400 provided by the embodiment of the present application mainly includes an LLC resonant conversion unit 401 and a first voltage regulation circuit 402 . The LLC resonance conversion unit 401 includes a first input end 11 , a second input end 12 , a first output end 13 and a second output end 14 . The first voltage regulating circuit 402 includes a third input terminal 21 , a fourth input terminal 22 , a third output terminal 23 and a fourth output terminal 24 .
其中，LLC谐振转换单元401的第一输入端11和第二输入端12用于接收直流转换器400的第一输入电压Vi1，第一调压电路402的第三输入端21和第四输入端22用于接收直流转换器400的第二输入端电压Vi2。其中，第一输入电压Vi1和第二输出电压Vi2构成直流转换器400的总输入电压Vi。即LLC谐振转换单元401的输入侧(第一输入端11和第二输入端12)与第一调压电路402的输入侧(第三输入端21和第四输入端22)串联。The first input terminal 11 and the second input terminal 12 of the LLC resonant conversion unit 401 are used to receive the first input voltage Vi1 of the DC converter 400 , and the third input terminal 21 and the fourth input terminal of the first voltage regulating circuit 402 22 is used for receiving the second input terminal voltage Vi2 of the DC converter 400 . The first input voltage Vi1 and the second output voltage Vi2 constitute the total input voltage Vi of the DC converter 400 . That is, the input side (the first input terminal 11 and the second input terminal 12 ) of the LLC resonance conversion unit 401 is connected in series with the input side (the third input terminal 21 and the fourth input terminal 22 ) of the first voltage regulating circuit 402 .
由于LLC谐振转换单元401的输入侧和第一调压电路402的输入侧串联，因此LLC 谐振转换单元401和第一调压电路402具有相同的输入电流。同时，如图4所示，输入端11和12之间的电压为Vi1，输入端21与输入端22之间的电压为Vi2，输入电压Vi1与输入电压Vi2之和为直流转换器400的总输入电压Vi。Since the input side of the LLC resonant conversion unit 401 and the input side of the first voltage regulator circuit 402 are connected in series, the LLC resonant conversion unit 401 and the first voltage regulator circuit 402 have the same input current. Meanwhile, as shown in FIG. 4 , the voltage between the input terminals 11 and 12 is Vi1, the voltage between the input terminal 21 and the input terminal 22 is Vi2, and the sum of the input voltage Vi1 and the input voltage Vi2 is the total of the DC converter 400. Input voltage Vi.
本申请实施例中，LLC谐振转换单元401和第一调压电路402均可以实现电压转换功能。其中，LLC谐振转换单元401可以对输入电压Vi1进行转换，并通过输出端13和输出端14输出转换后的电压。第一调压电路402可以对输入电压Vi2进行转换，并通过输出端23和输出端24输出转换后的电压。其中，LLC谐振转换单元401中包括逆变电路、谐振电路、变压器和整流电路。In this embodiment of the present application, both the LLC resonance conversion unit 401 and the first voltage regulation circuit 402 can implement a voltage conversion function. The LLC resonance conversion unit 401 can convert the input voltage Vi1 and output the converted voltage through the output terminal 13 and the output terminal 14 . The first voltage regulating circuit 402 can convert the input voltage Vi2 and output the converted voltage through the output terminal 23 and the output terminal 24 . The LLC resonance conversion unit 401 includes an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
采用上述LLC谐振转换单元对输入电压Vi1进行转换时，逆变电路将通过输入端11和12接收的输入电压Vi1转换为交流电压，将交流电压通过谐振电路和变压器传输给整流电路，整流电路将变压器输出的交流电转换为直流电压后输出。When the above LLC resonant conversion unit is used to convert the input voltage Vi1, the inverter circuit converts the input voltage Vi1 received through the input terminals 11 and 12 into an AC voltage, and transmits the AC voltage to the rectifier circuit through the resonant circuit and the transformer. The AC power output by the transformer is converted into DC voltage and then output.
如图4所示，LLC谐振转换单元401的输出端和第一调压电路402的输出端连接，LLC谐振转换单元401的输出端13和第一调压电路402的输出端23连接，LLC谐振转换单元401的输出端14和第一调压电路402的输出端24连接，即，LLC谐振转换单元401的输出侧(第一输出端13和第二输出端14)与第一调压电路402的输出侧(第三输出端23和第四输出端24)并联，因此LLC谐振转换单元401和第一调压电路402的输出电压Vo相同，该输出电压Vo也就是直流转换器400的输出电压。As shown in FIG. 4 , the output terminal of the LLC resonant conversion unit 401 is connected to the output terminal of the first voltage regulator circuit 402 , the output terminal 13 of the LLC resonant conversion unit 401 is connected to the output terminal 23 of the first voltage regulator circuit 402 , and the LLC resonates The output terminal 14 of the conversion unit 401 is connected to the output terminal 24 of the first voltage regulating circuit 402 , that is, the output side (the first output terminal 13 and the second output terminal 14 ) of the LLC resonance conversion unit 401 is connected to the first voltage regulating circuit 402 The output side (the third output terminal 23 and the fourth output terminal 24 ) of the DC converter are connected in parallel, so the output voltage Vo of the LLC resonant conversion unit 401 and the first voltage regulating circuit 402 is the same, and the output voltage Vo is the output voltage of the DC converter 400 .
本申请实施例所提供的直流转换器400具有高转换效率。举例来说，假设直流转换器400的输入电流为Ii，输出电流为Io。LLC谐振转换单元401的输出电流为Io1，第一调压电路402的输出电流为Io2。由于LLC谐振转换单元401输出侧和第一调压电路402的输出侧并联，因此LLC谐振转换单元401的输出电流Io1与第一调压电路402的输出电流Io2之和为直流转换器400的输出电流Io，即Io1+Io2＝Io。The DC converter 400 provided by the embodiments of the present application has high conversion efficiency. For example, it is assumed that the input current of the DC converter 400 is Ii and the output current is Io. The output current of the LLC resonant conversion unit 401 is Io1, and the output current of the first voltage regulating circuit 402 is Io2. Since the output side of the LLC resonant conversion unit 401 is connected in parallel with the output side of the first voltage regulator circuit 402 , the sum of the output current Io1 of the LLC resonant conversion unit 401 and the output current Io2 of the first voltage regulator circuit 402 is the output of the DC converter 400 Current Io, that is, Io1+Io2=Io.
假设LLC谐振转换单元401的效率为a％，LLC谐振转换单元401的效率a％可以理解为LLC谐振转换单元401的输出功率与LLC谐振转换单元401的输入功率的比值(多以百分比的形式表示)，a可以为大于或等于0，且小于或等于100的任一取值。LLC谐振转换单元的效率满足以下公式一：Assuming that the efficiency of the LLC resonant conversion unit 401 is a%, the efficiency a% of the LLC resonant conversion unit 401 can be understood as the ratio of the output power of the LLC resonant conversion unit 401 to the input power of the LLC resonant conversion unit 401 (mostly expressed in the form of a percentage). ), a can be any value greater than or equal to 0 and less than or equal to 100. The efficiency of the LLC resonant conversion unit satisfies the following formula 1:
(N1*Vo)*Ii*a％＝Vo*Io1  (公式一)(N1*Vo)*Ii*a%=Vo*Io1 (Formula 1)
其中，N1为LLC谐振转换单元401的变比，以下简称为第一变比N1，N1*Vo＝Vi1，Vi1为LLC谐振转换单元的输入电压。Wherein, N1 is the transformation ratio of the LLC resonance conversion unit 401, hereinafter referred to as the first transformation ratio N1, N1*Vo=Vi1, and Vi1 is the input voltage of the LLC resonance conversion unit.
假设第一调压电路402的效率为b％，第一调压电路402的效率b％可以理解为第一调压电路402的输出功率与第一调压电路402的输入功率的比值(多以百分比的形式表示)，b可以为大于或等于0，且小于或等于100的任一取值。第一调压电路的效率满足以下公式二：Assuming that the efficiency of the first voltage regulating circuit 402 is b%, the efficiency b% of the first voltage regulating circuit 402 can be understood as the ratio of the output power of the first voltage regulating circuit 402 to the input power of the first voltage regulating circuit 402 (more than In the form of percentage), b can be any value greater than or equal to 0 and less than or equal to 100. The efficiency of the first voltage regulating circuit satisfies the following formula 2:
(Vi-N1*Vo)*Ii*b％＝Vo*Io2  (公式二)(Vi-N1*Vo)*Ii*b%=Vo*Io2 (Formula 2)
结合公式一和公式二可见，直流转换器400的效率满足以下公式三：Combining formula 1 and formula 2, it can be seen that the efficiency of the DC converter 400 satisfies the following formula 3:
Figure PCTCN2021133101-appb-000001
Figure PCTCN2021133101-appb-000001
其中，η表示直流转换器400的效率。由公式三进一步可以得到如下公式四：Here, η represents the efficiency of the DC converter 400 . From formula three, the following formula four can be obtained:
Figure PCTCN2021133101-appb-000002
Figure PCTCN2021133101-appb-000002
由公式四可见，在LLC谐振转换单元401的效率a％大于第一调压电路402的效率b％时，
Figure PCTCN2021133101-appb-000003
为正值，且当N1的数值越大，直流转换器的效率η越大。由此可见，相较于图2所示的两级转换器结构，本申请图4所示直流转换器600可以通过调整LLC谐振转换单元401的电压转换档位实现更大的效率。其中，每一个电压转换档位对应LLC谐振转换单元401的一个变比。 It can be seen from formula 4 that when the efficiency a% of the LLC resonant conversion unit 401 is greater than the efficiency b% of the first voltage regulating circuit 402,
Figure PCTCN2021133101-appb-000003
is a positive value, and when the value of N1 is larger, the efficiency η of the DC converter is larger. It can be seen that, compared with the two-stage converter structure shown in FIG. 2 , the DC converter 600 shown in FIG. 4 of the present application can achieve higher efficiency by adjusting the voltage conversion gear of the LLC resonant conversion unit 401 . Wherein, each voltage conversion gear corresponds to a transformation ratio of the LLC resonance conversion unit 401 .
需要说明的是，为了实现LLC谐振转换单元的效率，LLC谐振转换单元处于多个电压转换档位中的任一电压转换档位时，逆变电路输出的交流电压的周期与谐振电路的谐振周期相同、且LLC谐振转换单元的输出电压大于零。It should be noted that, in order to achieve the efficiency of the LLC resonant conversion unit, when the LLC resonant conversion unit is in any voltage conversion gear among multiple voltage conversion gears, the period of the AC voltage output by the inverter circuit and the resonance period of the resonant circuit are The same, and the output voltage of the LLC resonant conversion unit is greater than zero.
具体实现时，LLC谐振转换单元401和第一调压电路402可以由开关管、二极管、电感、电容等器件组成。LLC谐振转换单元401和第一调压电路402的工作状态可以通过调节这些器件(例如开关管)的工作状态来实现调整LLC谐振转换单元401和第一调压电路402的变比。During specific implementation, the LLC resonant conversion unit 401 and the first voltage regulating circuit 402 may be composed of devices such as switch tubes, diodes, inductors, and capacitors. The working states of the LLC resonant conversion unit 401 and the first voltage regulator circuit 402 can be adjusted by adjusting the work states of these devices (eg, switches) to adjust the transformation ratio of the LLC resonant conversion unit 401 and the first voltage regulator circuit 402 .
本申请中，可以通过控制器实现上述工作状态的调节。即，直流转换器400还可以包括控制器403，如图5所示，该控制器403分别与LLC谐振转换单元401和第一调压电路402连接，可以用于控制LLC谐振转换单元401将第一输入电压Vi1转换为直流转换器400的输出电压V0，控制第一调压电压402将第二输入电压Vi2转换为直流转换器400的输出电压Vo，以及根据直流转换器的目标变比，调整LLC谐振转换单元401的电压转换档位。其中，目标变比为总输入电压和直流转换器的目标输出电压之间的比值。In the present application, the above-mentioned adjustment of the working state can be realized by the controller. That is, the DC converter 400 may further include a controller 403. As shown in FIG. 5, the controller 403 is respectively connected to the LLC resonant conversion unit 401 and the first voltage regulating circuit 402, and can be used to control the LLC resonant conversion unit 401 to convert the An input voltage Vi1 is converted into the output voltage V0 of the DC converter 400, the first voltage regulation voltage 402 is controlled to convert the second input voltage Vi2 into the output voltage Vo of the DC converter 400, and according to the target transformation ratio of the DC converter, the adjustment The voltage conversion gear of the LLC resonance conversion unit 401 . The target transformation ratio is the ratio between the total input voltage and the target output voltage of the DC converter.
具体地，若直流转换器400的各电路中的开关管为金属氧化物半导体(metal oxide semiconductor，MOS)管，该控制器403可以与MOS管的栅极连接，从通过控制MOS管的通断使得直流转换器400实现电压转换；若直流转换器400的各电路中的开关管为双极结型晶体管(bipolar junction transistor，BJT)，该控制器403可以与BJT的基极连接，从通过控制BJT的通断使得直流转换器400实现电压转换。Specifically, if the switching transistors in each circuit of the DC converter 400 are metal oxide semiconductor (MOS) transistors, the controller 403 can be connected to the gate of the MOS transistor to control the on-off of the MOS transistor. Make the DC converter 400 realize voltage conversion; if the switches in each circuit of the DC converter 400 are bipolar junction transistors (bipolar junction transistors, BJT), the controller 403 can be connected to the base of the BJT, from the control The on-off of the BJT enables the DC converter 400 to realize voltage conversion.
具体实现时，控制器403可以是微控制单元(micro controller unit，MCU)、中央处理器(central processing unit，CPU)、数字信号处理器(digital singnal processor，DSP)中的任一种。当然，控制器403的具体形态不限于上述举例。In specific implementation, the controller 403 may be any one of a microcontroller unit (microcontroller unit, MCU), a central processing unit (central processing unit, CPU), and a digital signal processor (digital signal processor, DSP). Of course, the specific form of the controller 403 is not limited to the above examples.
此外，由于本申请实施例中LLC谐振转换单元401和第一调压电路402分别独立进行电压转换，LLC谐振转换单元401和第一调压电路402的开关频率无需保持一致。In addition, since the LLC resonant conversion unit 401 and the first voltage regulator circuit 402 perform voltage conversion independently in the embodiment of the present application, the switching frequencies of the LLC resonant conversion unit 401 and the first voltage regulator circuit 402 do not need to be consistent.
由公式四可见，LLC谐振转换单元401的效率a％大于第一调压电路402的效率b％，且第一变比N1取值越大，则直流转换器400的效率越高。在输出电压Vo固定的情况下，N1的取值越大，LLC谐振转换单元402的输入电压Vi1(Vi1＝N1*Vo)便越大，传输更多的电压。因此，在LLC谐振转换单元401的效率a％大于第一调压电路的效率b％时，控制器403可以使LLC谐振转换单元401具有更大的变比，使第一调压电路402具有更小的变比。It can be seen from formula 4 that the efficiency a% of the LLC resonant conversion unit 401 is greater than the efficiency b% of the first voltage regulating circuit 402, and the larger the value of the first transformation ratio N1, the higher the efficiency of the DC converter 400. When the output voltage Vo is fixed, the larger the value of N1 is, the larger the input voltage Vi1 (Vi1=N1*Vo) of the LLC resonant conversion unit 402 is, and more voltage is transmitted. Therefore, when the efficiency a% of the LLC resonant conversion unit 401 is greater than the efficiency b% of the first voltage regulation circuit, the controller 403 can make the LLC resonant conversion unit 401 have a larger transformation ratio, and make the first voltage regulation circuit 402 have a higher transformation ratio. Small ratio.
理想情况下，若第一调压电路402具有降压功能，可以是第一调压电路402的变比N2为1，即Vo＝Vi2。也就是说，第一调压电路402只进行了电压传输，并未进行电压转换。而第一调压电路402的损耗主要是在电压转换过程中产生的，因此当第二变比N2为1时，可以认为第一调压电路402的损耗最小、且传输更少的功率。Ideally, if the first voltage regulating circuit 402 has a step-down function, the transformation ratio N2 of the first voltage regulating circuit 402 may be 1, that is, Vo=Vi2. That is to say, the first voltage regulating circuit 402 only performs voltage transmission and does not perform voltage conversion. The loss of the first voltage regulating circuit 402 is mainly generated during the voltage conversion process, so when the second transformation ratio N2 is 1, it can be considered that the first voltage regulating circuit 402 has the smallest loss and transmits less power.
若第一调压电路402具有升压功能，可以提高第一调压电路的调压范围。理想情况下， 可以使第一调压电路402的变比N2小于1、且接近0，也就是说，第一调压电路402的输入电压Vi2越小，第一调压电路402传输更少功率。If the first voltage regulating circuit 402 has a boosting function, the voltage regulating range of the first voltage regulating circuit can be increased. Ideally, the transformation ratio N2 of the first voltage regulating circuit 402 can be made smaller than 1 and close to 0, that is to say, the smaller the input voltage Vi2 of the first voltage regulating circuit 402 is, the less power the first voltage regulating circuit 402 transmits .
如前所述，在LLC谐振转换单元401的效率a％大于第一调压电路402的效率b％的情况下，为LLC谐振转换单元402配置较大的变比，可以使LLC谐振转换单元401传输更多的功率，有利于进一步提高直流转换器400的效率。然而，由于直流转换器400的应用场景并不十分稳定，如电池电压出现波动、负载的工作电压变化等等，因此LLC谐振转换单元401的变比往往需要随应用场景的改变动态变化。As mentioned above, when the efficiency a% of the LLC resonant conversion unit 401 is greater than the efficiency b% of the first voltage regulating circuit 402, configuring a larger transformation ratio for the LLC resonant conversion unit 402 can make the LLC resonant conversion unit 401 Transmitting more power is beneficial to further improve the efficiency of the DC converter 400 . However, since the application scenarios of the DC converter 400 are not very stable, such as fluctuations in battery voltage, changes in the operating voltage of the load, etc., the transformation ratio of the LLC resonant conversion unit 401 often needs to be dynamically changed with changes in the application scenarios.
在一种可能的实现方式中，本申请实施例中第一变比N1和第二变比N2是可调的。本申请实施例中，控制器403还可以检测当前的总输入电压Vi和直流转换的目标输出电压Va。其中，当前的总输入电压Vi可以是直流转换器400连接的电池的输出电压，直流转换器400的目标输出电压Va可以是负载当前所需的工作电压。如前所述，在连接的电池放电的过程中，电池电压会逐渐降低。具体来说，与输出端13和输出端14连接的负载有可能存在多种工作状态，在不同工作状态下所需的工作电压不同。例如，负载可以为GPU或者蓄电池，当蓄电池的充电过程中，蓄电池的两端的电压逐渐增大。In a possible implementation manner, in the embodiment of the present application, the first transformation ratio N1 and the second transformation ratio N2 are adjustable. In this embodiment of the present application, the controller 403 may also detect the current total input voltage Vi and the target output voltage Va of DC conversion. The current total input voltage Vi may be the output voltage of the battery connected to the DC converter 400 , and the target output voltage Va of the DC converter 400 may be the operating voltage currently required by the load. As previously mentioned, the battery voltage will gradually decrease during the discharge of the connected battery. Specifically, the loads connected to the output terminal 13 and the output terminal 14 may have various working states, and the required working voltages are different in different working states. For example, the load may be a GPU or a battery, and during the charging process of the battery, the voltage at both ends of the battery gradually increases.
应理解，直流转换器400的输出电压Vo可能与目标输出电压Va相同，也可能与目标输出电压Va不同。直流转换器的输出电压Vo与目标输出电压Va不同时，控制器可以调节直流转换器的变比，从而将直流转换器的输出电压Vo调节为所需的目标输出电压Va。其中，目标输出电压为负载实际需要的电压。It should be understood that the output voltage Vo of the DC converter 400 may be the same as the target output voltage Va, or may be different from the target output voltage Va. When the output voltage Vo of the DC converter is different from the target output voltage Va, the controller can adjust the transformation ratio of the DC converter, so as to adjust the output voltage Vo of the DC converter to the desired target output voltage Va. The target output voltage is the voltage actually required by the load.
示例性的，控制器403可以检测当前的输出电压Vo和总输入电压Vi。在当前的输出电压Vo与直流转换器400的目标输出电压Va不同时，控制器403可以根据总输入电压Vi调节LLC谐振转换单元401和第一调压电路402的变比，从而将直流转换器400的输出电压Vo调节至目标输出电压Va。Exemplarily, the controller 403 may detect the current output voltage Vo and the total input voltage Vi. When the current output voltage Vo is different from the target output voltage Va of the DC converter 400, the controller 403 can adjust the transformation ratio of the LLC resonant conversion unit 401 and the first voltage regulating circuit 402 according to the total input voltage Vi, so as to convert the DC converter The output voltage Vo of 400 is adjusted to the target output voltage Va.
具体来说，控制器403可以执行如图6所示的控制方法调节上述图4中LLC谐振转换单元401和第一调压电路402的变比，提升直流转换器400的转换效率，主要包括以下步骤：Specifically, the controller 403 can execute the control method shown in FIG. 6 to adjust the transformation ratio of the LLC resonant conversion unit 401 and the first voltage regulation circuit 402 in FIG. 4 to improve the conversion efficiency of the DC converter 400 , which mainly includes the following: step:
S601：计算目标变比，目标变比为直流转换器400输入电压与直流转换器的目标输出电压之间的变比。其中，目标变比为Na＝Vi/Va。S601: Calculate a target transformation ratio, where the target transformation ratio is the transformation ratio between the input voltage of the DC converter 400 and the target output voltage of the DC converter. The target transformation ratio is Na=Vi/Va.
S602：根据目标变比与第一调压电路的最小变比，从LLC谐振转换单元的多个电压转换档位中确定LLC谐振转换单元的第一变比。S602: According to the target transformation ratio and the minimum transformation ratio of the first voltage regulating circuit, determine the first transformation ratio of the LLC resonance transformation unit from a plurality of voltage transformation gears of the LLC resonance transformation unit.
其中，第一变比N1小于或等于目标变比Na与第一调压电路402最小变比的差值、且小于或等于LLC谐振转换单元401的最大变比。The first transformation ratio N1 is less than or equal to the difference between the target transformation ratio Na and the minimum transformation ratio of the first voltage regulating circuit 402 , and is less than or equal to the maximum transformation ratio of the LLC resonance conversion unit 401 .
一般来说，控制器403可以通过控制LLC谐振转换单元401的逆变电路中的开关管的驱动信号的时序以及开关频率改变LLC谐振转换单元401的电压转换档位，从而实现调整第一变比N1。控制器确定N1具体取值与LLC谐振转换单元的结构有关，控制器可以根据LLC谐振转换单元的具体结构灵活选择设置LLC谐振转换单元的变比的实现方式。Generally speaking, the controller 403 can change the voltage conversion gear of the LLC resonant conversion unit 401 by controlling the timing and switching frequency of the driving signal of the switch tube in the inverter circuit of the LLC resonant conversion unit 401 , so as to adjust the first transformation ratio N1. The specific value of N1 determined by the controller is related to the structure of the LLC resonant conversion unit, and the controller can flexibly select an implementation manner of setting the transformation ratio of the LLC resonant conversion unit according to the specific structure of the LLC resonant conversion unit.
S603：根据第一变比N1和目标变比确定第一调压电路402的第二变比N2。S603: Determine the second transformation ratio N2 of the first voltage regulating circuit 402 according to the first transformation ratio N1 and the target transformation ratio.
具体来说，控制器402可以根据设置的第一变比N1确定调节LLC谐振转换单元401变比后的输入电压Vi1，即调节后的输入电压Vi1为设置的第一变比N1与目标输出电压Va之间的乘积(Vi1＝N1*Va)。Specifically, the controller 402 can determine the input voltage Vi1 after adjusting the ratio of the LLC resonant conversion unit 401 according to the set first ratio N1, that is, the adjusted input voltage Vi1 is the set first ratio N1 and the target output voltage The product between Va (Vi1=N1*Va).
控制器403进而可以根据当前的总输入电压Vi确定第一调压电路402调节后的输入电 压Vi2，即Vi2＝Vi-Vi1＝Vi-N1*Va。也就是说，第二变比N2应设置为N2＝(Vi-N1*Va)/Va。控制器可以根据第一调压电路402的具体结构灵活选择设置第一调压电路402的变比的实现方式。The controller 403 can further determine the input voltage Vi2 adjusted by the first voltage regulating circuit 402 according to the current total input voltage Vi, that is, Vi2=Vi-Vi1=Vi-N1*Va. That is, the second transformation ratio N2 should be set as N2=(Vi-N1*Va)/Va. The controller may flexibly select an implementation manner of setting the transformation ratio of the first voltage regulating circuit 402 according to the specific structure of the first voltage regulating circuit 402 .
为了便于理解，本申请实施例接下来以LLC谐振转换单元的效率为a％，第一调压电路的效率为b％的情况为例对图6所示的控制方法进行说明。For ease of understanding, the embodiments of the present application describe the control method shown in FIG. 6 by taking the case where the efficiency of the LLC resonant conversion unit is a% and the efficiency of the first voltage regulating circuit is b% as an example.
本申请实施例中第一变比N1具有多个非连续可调变比，每一个变比对应LLC谐振转换单元401的第一个电压转换档位。In the embodiment of the present application, the first transformation ratio N1 has a plurality of non-continuously adjustable transformation ratios, and each transformation ratio corresponds to the first voltage transformation gear of the LLC resonant conversion unit 401 .
如前，LLC谐振转换单元401的效率a％大于第一调压电路402的效率b％，则应尽量增大LLC谐振转换单元401的输入电压Vi1。因此，在LLC谐振转换单元401具有非连续的多个可调变比的情况下，第一变比N1可以是LLC谐振转换单元中的多个可调变比中小于目标变比Na与第一调压电路402最小变比的差值、且与目标变比Na最接近的可调变比。As before, if the efficiency a% of the LLC resonant conversion unit 401 is greater than the efficiency b% of the first voltage regulating circuit 402, the input voltage Vi1 of the LLC resonant conversion unit 401 should be increased as much as possible. Therefore, when the LLC resonant conversion unit 401 has a plurality of non-continuous adjustable ratios, the first transformation ratio N1 may be a ratio smaller than the target transformation ratio Na and the first variable ratio N1 among the multiple adjustable ratios in the LLC resonance transformation unit The difference of the minimum transformation ratio of the voltage regulating circuit 402 and the adjustable transformation ratio closest to the target transformation ratio Na.
以LLC谐振转换单元402的多个可调变比的取值为连续的整数为例(如可调变比为4、3、2、1)，控制器可403以采用如图7所示的方法，调节第一变比N1和第二变比N2。如图7所示，主要包括以下步骤：Taking the value of the variable ratios of the LLC resonant conversion unit 402 as continuous integers as an example (for example, the variable ratios are 4, 3, 2, and 1), the controller 403 can use the variable ratio shown in FIG. 7 . method, adjust the first transformation ratio N1 and the second transformation ratio N2. As shown in Figure 7, it mainly includes the following steps:
S701：检测当前的总输入电压Vi和目标输出电压Va。S701: Detect the current total input voltage Vi and the target output voltage Va.
S702：控制器计算目标变比Na。其中，目标变比Na为总输入电压Vi与目标输出电压Va之间的比值，即Na＝Vi/Va。S702: The controller calculates the target transformation ratio Na. The target transformation ratio Na is the ratio between the total input voltage Vi and the target output voltage Va, that is, Na=Vi/Va.
S703：检测第一调压电路是否为具有升压功能，若是执行704，否则执行705。S703 : Detect whether the first voltage regulating circuit has a boosting function, if yes, go to 704 , otherwise go to 705 .
S704：若第一调压电路具有升压功能，则电压转换档位的取值范围为小于或等于目标变比Na。其中，每一个电压转换档位对应一个第一电压变比N1。S704: If the first voltage regulating circuit has a boosting function, the value range of the voltage conversion gear is less than or equal to the target transformation ratio Na. Wherein, each voltage conversion gear corresponds to a first voltage transformation ratio N1.
若第一调压电路具有升压功能，在理想情况下第一调压电路的第二变比N2可以接近与0，此时。此时，Vi2<Va，第一变比N1＝(Vi-Vi2)/Va≈Na。也就是说，在理想情况下，第二变比N2≈0。因此，第一变比N1的取值范围为N1<Na、且N1小于或者LLC谐振转换单元的最大电压转换档位。If the first voltage regulating circuit has a boosting function, in an ideal situation, the second transformation ratio N2 of the first voltage regulating circuit can be close to 0, at this time. At this time, Vi2<Va, the first transformation ratio N1=(Vi−Vi2)/Va≈Na. That is to say, in an ideal situation, the second transformation ratio N2≈0. Therefore, the value range of the first transformation ratio N1 is N1<Na, and N1 is smaller than or the maximum voltage conversion gear of the LLC resonance conversion unit.
S705：若第一调压电路具有降压功能，则电压转换档位的取值范围为小于目标变比Na-1。S705: If the first voltage regulating circuit has a step-down function, the value range of the voltage conversion gear is smaller than the target transformation ratio Na-1.
若第一调压电路具有降压功能，在理想情况下第一调压电路的第二变比N2可以达到1。此时，Vi2＝Va，第一变比N1＝(Vi-Vi2)/Va＝Na-1。也就是说，在理想情况下，第一变比N1＝Na-1。因此，第一变比N1的取值范围为N1≦Na-1、且小于或等于LLC谐振转换单元的最大电压转换档位。If the first voltage regulating circuit has a step-down function, the second transformation ratio N2 of the first voltage regulating circuit can reach 1 under ideal conditions. At this time, Vi2=Va, and the first transformation ratio N1=(Vi-Vi2)/Va=Na-1. That is to say, in an ideal situation, the first transformation ratio N1=Na-1. Therefore, the value range of the first transformation ratio N1 is N1≦Na−1, and is less than or equal to the maximum voltage conversion gear of the LLC resonant conversion unit.
S706：将LLC谐振转换单元的电压转换档位的取值范围内最大的电压转换档位确定为第一变比。S706: Determine the largest voltage conversion gear within the value range of the voltage conversion gears of the LLC resonance conversion unit as the first transformation ratio.
例如，假设LLC谐振转换单元具有3、2、1三个电压转换档位。如图8所示，总输入电压Vi为3.4V，目标输出电压Va为1V。此时，目标变比Na为3.4，若第一调压电路402具有降压功能，则N1≦Na-1＝2.4，因此LLC谐振转换单元401的电压转换档位可为1或2，N1max＝2，因此控制器403可以将第一变比N1设置为2。若第一调压电路具有升压功能，则N1<Na≈3.4，因此LLC谐振转换单元的电压转换档位可为1、2或3，N1max＝3，因此控制器可以将第一变比N1设置为3。For example, it is assumed that the LLC resonant conversion unit has three voltage conversion gears of 3, 2, and 1. As shown in FIG. 8, the total input voltage Vi is 3.4V, and the target output voltage Va is 1V. At this time, the target transformation ratio Na is 3.4. If the first voltage regulating circuit 402 has a step-down function, then N1≦Na−1=2.4, so the voltage conversion gear of the LLC resonant conversion unit 401 can be 1 or 2, and N1max= 2, so the controller 403 can set the first transformation ratio N1 to 2. If the first voltage regulating circuit has a boost function, N1<Na≈3.4, so the voltage conversion gear of the LLC resonant conversion unit can be 1, 2 or 3, and N1max=3, so the controller can change the first transformation ratio N1 Set to 3.
S707：计算所述LLC谐振转换单元处于所述第一变比时所述LLC谐振转换单元的目标输入电压。S707: Calculate the target input voltage of the LLC resonance conversion unit when the LLC resonance conversion unit is in the first transformation ratio.
S708：计算直流转换器输入电压与目标输入电压的第一电压差。S708: Calculate a first voltage difference between the input voltage of the DC converter and the target input voltage.
S709：将所述第一电压差与所述直流转换器的输出电压之间的变比确定为所述第二变比。S709: Determine a transformation ratio between the first voltage difference and the output voltage of the DC converter as the second transformation ratio.
如前所述，如输入电压如图8所示，控制器可以将第一变比N1设置为3，进而使得输入电压Vi1为3V，输入电压Vi2＝Vi-Vi1＝0.4V，则第二变比N2＝Vi2/Vo＝0.4/1＝0.4。As mentioned above, as the input voltage is shown in FIG. 8 , the controller can set the first transformation ratio N1 to 3, so that the input voltage Vi1 is 3V, and the input voltage Vi2=Vi-Vi1=0.4V, then the second transformation ratio N1 is set to 3. The ratio N2=Vi2/Vo=0.4/1=0.4.
由上述实施例可见，基于本申请实施例所提供的直流转换器400，控制器403可以根据直流转换器的总输入电压Vi和目标输出电压Va，灵活调节LLC谐振转换单元401和第一调压电路的变比，使得在不同的总输入电压Vi和目标输出电压Va的应用场景下，LLC谐振转换单元401皆可以在适配应用场景的同时尽可能接收到较大的输入电压Vi1。结合上述公式四可见，在LLC谐振转换单元的效率a％、第一调压电路的效率b％和输出电压Vo固定的情况下，当LLC谐振转换单元的输入电压Vi1＝N1*Vo增大时，直流转换器的效率也会随之增大。因此，采用本申请实施例图6和图8所示的设置第一变比N1和第二变比N2的方法，有利于进一步提高直流转换器400的效率。It can be seen from the above embodiments that, based on the DC converter 400 provided by the embodiments of the present application, the controller 403 can flexibly adjust the LLC resonant conversion unit 401 and the first voltage regulation according to the total input voltage Vi and the target output voltage Va of the DC converter The transformation ratio of the circuit enables the LLC resonant conversion unit 401 to receive a larger input voltage Vi1 as much as possible while adapting to the application scenarios under different application scenarios of the total input voltage Vi and the target output voltage Va. Combining the above formula 4, it can be seen that under the condition that the efficiency a% of the LLC resonant conversion unit, the efficiency b% of the first voltage regulating circuit and the output voltage Vo are fixed, when the input voltage Vi1=N1*Vo of the LLC resonant conversion unit increases , the efficiency of the DC converter will also increase. Therefore, using the method for setting the first transformation ratio N1 and the second transformation ratio N2 shown in FIGS. 6 and 8 in the embodiment of the present application is beneficial to further improve the efficiency of the DC converter 400 .
在一种可实现的方式中，在采用本申请实施例提供的直流转换器为负载供电过程中，若因为输入侧接收的电压或者输出侧负载发生变化造成的输出电压Vo偏离目标输出电压Va时，可以采用图6和图8所示的设置第一变比N1和第二变比N2的方法，重新配置LLC谐振转换单元401和第一调压电路的变比。In an achievable manner, in the process of using the DC converter provided by the embodiment of the present application to supply power to the load, if the output voltage Vo deviates from the target output voltage Va due to the voltage received at the input side or the load on the output side changes , the method of setting the first transformation ratio N1 and the second transformation ratio N2 shown in FIG. 6 and FIG. 8 can be used to reconfigure the transformation ratios of the LLC resonant conversion unit 401 and the first voltage regulating circuit.
在另一种可实现的方式中，在采用本申请实施例提供的直流转换器为负载供电过程中，若因为输入侧接收的电压或者输出侧负载发生变化造成的输出电压Vo偏离目标输出电压Va时，可以通过调节第一调压电路402的变比，实现输出电压Vo与目标输出电压Va。In another achievable manner, in the process of using the DC converter provided by the embodiment of the present application to supply power to the load, if the output voltage Vo deviates from the target output voltage Va due to the voltage received at the input side or the load on the output side changing , the output voltage Vo and the target output voltage Va can be achieved by adjusting the transformation ratio of the first voltage regulating circuit 402 .
在一示例中，在采用本申请实施例提供的直流转换器为负载供电时，若直流转换器输出端为13和14连接的负载增大，导致直流转换器的输出电压Vo小于目标输出电压Va时，可以调整第一调压电路402中开关管的占空比，实现调整第一调压电压402的变比N2，从而实现调整输出电压Vo，直至输出电压Vo等于目标输出电压Va。In an example, when the DC converter provided by the embodiment of the present application is used to supply power to the load, if the load connected to the output terminals 13 and 14 of the DC converter increases, the output voltage Vo of the DC converter is smaller than the target output voltage Va. When , the duty ratio of the switch tube in the first voltage regulation circuit 402 can be adjusted to adjust the transformation ratio N2 of the first voltage regulation voltage 402 , so as to adjust the output voltage Vo until the output voltage Vo is equal to the target output voltage Va.
在一示例中，在采用本申请实施例提供的直流转换器为负载供电时，若直流转换器输入侧连接的是蓄电池，则为负载供电过程中，蓄电池的电压逐渐降低，导致直流转换器的变比输出的电压Vo偏离目标输出电压Va，可以调整第一调压电路402中开关管的占空比，实现调整第一调压电压402的变比N2，从而实现调整输出电压Vo，直至输出电压Vo等于目标输出电压Va。In an example, when the DC converter provided in the embodiment of the present application is used to supply power to the load, if a battery is connected to the input side of the DC converter, the voltage of the battery is gradually reduced during the process of supplying power to the load, resulting in the voltage of the DC converter. If the output voltage Vo of the variable ratio deviates from the target output voltage Va, the duty cycle of the switch tube in the first voltage regulation circuit 402 can be adjusted to realize the adjustment of the transformation ratio N2 of the first voltage regulation voltage 402, so as to realize the adjustment of the output voltage Vo until the output is The voltage Vo is equal to the target output voltage Va.
如本申请实施例所公开的，LLC谐振转换单元401存在多种可能的实现结构。接下来，本申请实施例通过以下示例，对本申请实施例所提供的直流转换器400作进一步的示例性说明。As disclosed in the embodiments of the present application, the LLC resonant conversion unit 401 has various possible implementation structures. Next, the embodiments of the present application further illustrate the DC converter 400 provided by the embodiments of the present application by using the following examples.
直流转换器的示例一：Example 1 of a DC converter:
本申请实施例提供的一种直流转换器400，如图9所示。其中，LLC谐振转换单元401中的逆变电路包括：第一电容C1和由四个开关管S1、S2、S3、S4组成的第一H桥电路。谐振电路主要包括：谐振电感包括Lr和谐振电容Cr。变压器原边绕组与谐振电感Lr和谐振电容Cr串联，变压器副边绕组与由第二H桥电路组成的整流电路连接。其中，第二H桥电路主要包括开关管S5、S6、S7和S8。其中，谐振电感Lr可以是独立的电感，也可以是变压器原边绕组的漏感，或者谐振电感Lr由一部分独立电感以及一部分变压器原边绕组的漏感组成。其中，Lm为变压器的励磁绕组。A DC converter 400 provided by an embodiment of the present application is shown in FIG. 9 . The inverter circuit in the LLC resonance conversion unit 401 includes: a first capacitor C1 and a first H-bridge circuit composed of four switch tubes S1, S2, S3, and S4. The resonant circuit mainly includes: the resonant inductor includes Lr and the resonant capacitor Cr. The primary winding of the transformer is connected in series with the resonant inductor Lr and the resonant capacitor Cr, and the secondary winding of the transformer is connected with the rectifier circuit composed of the second H-bridge circuit. Wherein, the second H-bridge circuit mainly includes switch tubes S5, S6, S7 and S8. The resonant inductance Lr may be an independent inductance, or may be the leakage inductance of the primary winding of the transformer, or the resonant inductance Lr is composed of a part of the independent inductance and a part of the leakage inductance of the primary winding of the transformer. Among them, Lm is the excitation winding of the transformer.
其中，S1和S2串联构成第一H桥电路的第一桥臂，S3和S4串联构成第一H桥电路的第二桥臂，C1连接在第一桥臂的中间节点和第二桥臂的中间节点之间。也即，S2的第二端分别与S1的第一端和C1的一端连接，S4的第二端分别与S3的第一端和C2的另一端连接。具体来说，S1的第一端与输入端11连接，S3的第一端与输入端12连接。Among them, S1 and S2 are connected in series to form the first bridge arm of the first H-bridge circuit, S3 and S4 are connected in series to form the second bridge arm of the first H-bridge circuit, and C1 is connected between the middle node of the first bridge arm and the second bridge arm. between intermediate nodes. That is, the second end of S2 is connected to the first end of S1 and one end of C1 respectively, and the second end of S4 is connected to the first end of S3 and the other end of C2 respectively. Specifically, the first end of S1 is connected to the input end 11 , and the first end of S3 is connected to the input end 12 .
其中，S5和S6串联构成第二H桥电路的第一桥臂，S7和S8串联构成第二H桥电路的第二桥臂。也即，S6的第二端与S5的第一端连接，S8的第二端与S7的第一端，S5的第一端分别S7的第一端和变压器副边绕组的一端连接，S6的第二端分别与S8的第二端和变压器副边绕组的另一端连接。具体来说，第二H桥电路的第一桥臂的中间节点和第二桥臂的中间节点分别与输出端12和输出端14连接。也即，S5的第二端与输出端13连接，S7的第二端与输出端14连接。Wherein, S5 and S6 are connected in series to form the first bridge arm of the second H-bridge circuit, and S7 and S8 are connected in series to form the second bridge arm of the second H-bridge circuit. That is, the second end of S6 is connected to the first end of S5, the second end of S8 is connected to the first end of S7, the first end of S5 is respectively connected to the first end of S7 and one end of the secondary winding of the transformer, and the first end of S6 The second ends are respectively connected with the second end of S8 and the other end of the secondary winding of the transformer. Specifically, the middle node of the first bridge arm and the middle node of the second bridge arm of the second H-bridge circuit are respectively connected to the output end 12 and the output end 14 . That is, the second end of S5 is connected to the output end 13 , and the second end of S7 is connected to the output end 14 .
其中，S2的第二端和S4的第二端均谐振电容Cr的一端连接，Cr的另一端与谐振电感Lr的一端连接，Lr的另一端与变压器原边绕组的一端连接，变压器原边绕组的另一端与输入端12连接。Among them, the second end of S2 and the second end of S4 are both connected to one end of the resonant capacitor Cr, the other end of Cr is connected to one end of the resonant inductor Lr, the other end of Lr is connected to one end of the primary winding of the transformer, and the primary winding of the transformer is connected. The other end is connected to the input end 12 .
具体实现时，第一H桥电路具有多个电压转换比，多个电压转换比与LLC谐振转换单元401的多个电压转换档位一对一、且多个电压转换比与多个驱动信号一对一。其中，驱动信号用于控制第一H桥电路中开关管S1、S2、S3和S4的导通时序。其中，电压转换档位表征一种LLC谐振转换单元输入电压与LLC谐振转换单元的输出电压的比值关系，该比值关系即为本申请实施例中的第一变比N1。需要说明的是，在本申请提供的直流转换器中，LLC谐振转换单元具有多个电压转换档位，是指，LLC谐振转换单元的输入电压与LLC谐振转换单元的输出电压之间具有多个比值关系，比如，该多个比值关系为1:1、1.2:1、1.5:1、以及2:1等。则在不同的电压转换档位下，面对相同的输入电压，LLC谐振转换单元的输出电压是不同的。In specific implementation, the first H-bridge circuit has a plurality of voltage conversion ratios, the plurality of voltage conversion ratios and the plurality of voltage conversion gears of the LLC resonance conversion unit 401 are one-to-one, and the plurality of voltage conversion ratios are one-to-one with the plurality of driving signals to one. Wherein, the driving signal is used to control the turn-on sequence of the switches S1 , S2 , S3 and S4 in the first H-bridge circuit. The voltage conversion gear represents a ratio relationship between the input voltage of the LLC resonant conversion unit and the output voltage of the LLC resonant conversion unit, and the ratio relationship is the first transformation ratio N1 in the embodiment of the present application. It should be noted that, in the DC converter provided in this application, the LLC resonant conversion unit has multiple voltage conversion gears, which means that there are multiple voltages between the input voltage of the LLC resonant conversion unit and the output voltage of the LLC resonant conversion unit. The ratio relationship, for example, the plurality of ratio relationships are 1:1, 1.2:1, 1.5:1, and 2:1. Then under different voltage conversion gears, facing the same input voltage, the output voltage of the LLC resonant conversion unit is different.
在一种可能实现方式中，如图9所示，直流转换器400还可以包括输入电容Cin1和输入电容Cin2。其中，输入电容Cin1的一端与输入端11连接，输入电容Cin1的另一端与输入端12连接，输入电容Cin1可以对第一输入电压Vi1进行滤波。输入电压Cin2的一端与输入端21连接，输入电压Cin2的另一端与输入端22连接，Cin2可以对第二输入电压Vi2进行滤波。In a possible implementation manner, as shown in FIG. 9 , the DC converter 400 may further include an input capacitor Cin1 and an input capacitor Cin2 . One end of the input capacitor Cin1 is connected to the input end 11 , the other end of the input capacitor Cin1 is connected to the input end 12 , and the input capacitor Cin1 can filter the first input voltage Vi1 . One end of the input voltage Cin2 is connected to the input end 21 , the other end of the input voltage Cin2 is connected to the input end 22 , and the Cin2 can filter the second input voltage Vi2 .
在一种可能实现方式中，如图9所示，直流转换器400还可以包括输出电容Cout。输出电容Cout的一端与LLC谐振转换单元401的输出端13连接，输出电容Cout的另一端与LLC谐振转换单元401的输出端14连接。输出电容Cout可以对输出电压Vo进行滤波，降低输出电压Vo波动。In a possible implementation manner, as shown in FIG. 9 , the DC converter 400 may further include an output capacitor Cout. One end of the output capacitor Cout is connected to the output end 13 of the LLC resonance conversion unit 401 , and the other end of the output capacitor Cout is connected to the output end 14 of the LLC resonance conversion unit 401 . The output capacitor Cout can filter the output voltage Vo to reduce the fluctuation of the output voltage Vo.
参见图9所示，以逆变电路输出的交流电的周期为T为例，当开关管S1、S2、S3和S4接收对应不同的驱动信号时，LLC谐振转换单元的变比满足以下关系：Referring to Fig. 9, taking the cycle of the alternating current output by the inverter circuit as T as an example, when the switches S1, S2, S3 and S4 receive corresponding different driving signals, the transformation ratio of the LLC resonant conversion unit satisfies the following relationship:
N1＝2N h*N L  (公式五) N1＝2N h *N L (Formula 5)
Nh＝Vi1/Vh  (公式六)Nh=Vi1/Vh (Formula 6)
其中，Vh为逆变电路的输出电压的峰峰值。N h表示输入电压Vi1与逆变电路输出电压的峰峰值之间的变比，NL为变压器原边绕组和副边绕组线圈匝数的变比。 Wherein, Vh is the peak-to-peak value of the output voltage of the inverter circuit. N h represents the transformation ratio between the input voltage Vi1 and the peak-to-peak value of the output voltage of the inverter circuit, and NL is the transformation ratio of the turns of the primary winding and the secondary winding of the transformer.
为了便于计算和理解，本申请实施例接下来以变压器的NL等于1为例进行说明，后续对此不再赘述。In order to facilitate calculation and understanding, the embodiments of the present application will be described by taking the NL of the transformer equal to 1 as an example for description, which will not be repeated hereafter.
需要说明的是，由于逆变电路输出的交流电的周期与谐振电路的谐振周期一致，才能 实现开关管软开关，保证LLC谐振转换单元401的效率。It should be noted that, since the cycle of the alternating current output by the inverter circuit is consistent with the resonant cycle of the resonant circuit, the soft switching of the switch tube can be realized and the efficiency of the LLC resonant conversion unit 401 is guaranteed.
图9所示的LLC谐振转换电路中的开关管S1、S2、S3和S4接收不同的驱动信号时，LLC谐振转换电路处于不同的状态、且具有不同的变比。当S1、S2、S3和S4接收不同驱动信号时，驱动信号与第一H桥电路输出电压对应关系可如表一所示。When the switches S1 , S2 , S3 and S4 in the LLC resonant conversion circuit shown in FIG. 9 receive different driving signals, the LLC resonant conversion circuit is in different states and has different transformation ratios. When S1 , S2 , S3 and S4 receive different driving signals, the corresponding relationship between the driving signals and the output voltage of the first H-bridge circuit may be as shown in Table 1.
表一Table I
   S1S1 S2S2 S3S3 S4S4 C 1 C 1 VhVh
状态①Status① 00 00 11 11 ---- 00
状态② Status ② 11 00 11 00 充电Charge Vi1/2Vi1/2
状态③ Status ③ 00 11 00 11 放电discharge Vi1/2Vi1/2
状态④ Status④ 11 11 00 00 ---- 1Vi11Vi1
当图9所示的LLC谐振转换单元401采用表一所示的驱动信号驱动开关管S1、S2、S3和S4的状态时，LLC谐振转换单元至少具有4和2两种可调变比。需要指出的是，可调变比是LLC谐振转换单元401理论上可以达到的变比，受限于寄生电阻、寄生电感等原因，LLC谐振转换单元401的实际变比与可调变比之间可能会有些许偏差，但并不影响本申请技术方案的实现。When the LLC resonant conversion unit 401 shown in FIG. 9 uses the driving signals shown in Table 1 to drive the states of the switches S1 , S2 , S3 and S4 , the LLC resonant conversion unit has at least two adjustable ratios of 4 and 2. It should be pointed out that the adjustable transformation ratio is the transformation ratio that the LLC resonant conversion unit 401 can theoretically achieve. Due to the parasitic resistance, parasitic inductance and other reasons, the difference between the actual transformation ratio of the LLC resonant transformation unit 401 and the adjustable transformation ratio is There may be some deviations, but it does not affect the realization of the technical solution of the present application.
下面结合实例对LLC谐振转换单元401的两个电压转换档位下的变比的过程进行详细说明。The following describes in detail the process of the transformation ratio under the two voltage conversion gears of the LLC resonance conversion unit 401 with reference to an example.
第一种实现方式：第一变比N1为4。The first implementation method: the first transformation ratio N1 is 4.
假设LLC谐振转换单元401中的各个开关管皆为高电压导通，低电压断开。在控制器403为LLC谐振转换单元401中的各个开关管提供如图10所示的驱动信号时，第一变比N1为4。其中，控制器按照状态②①③①的顺序发送驱动信号，来控制开关管进行状态切换。It is assumed that each switch in the LLC resonant conversion unit 401 is turned on at high voltage and turned off at low voltage. When the controller 403 provides the drive signals as shown in FIG. 10 for each switch tube in the LLC resonant conversion unit 401 , the first transformation ratio N1 is 4. Among them, the controller sends drive signals in the order of states ②①③① to control the switch tube to switch states.
如图10所示，交流电的周期为T，开关管S1、S2、S3和S4分别对应不同的驱动信号。As shown in FIG. 10 , the cycle of the alternating current is T, and the switches S1 , S2 , S3 and S4 correspond to different driving signals respectively.
在0至T/2的时间段内，各个开关管的状态可以如图11所示。其中，开关管S1和开关管S3导通，开关管S2和S4断开。In the time period from 0 to T/2, the state of each switch tube can be as shown in FIG. 11 . The switch S1 and the switch S3 are turned on, and the switches S2 and S4 are turned off.
在此情况下，开关管S1、电容C1、开关管S3、Cr、Lr和Lm构成通路，等效电路可以如图12所示。此时，V h为1/2Vi1。 In this case, the switch tube S1, the capacitor C1, the switch tube S3, Cr, Lr and Lm form a path, and the equivalent circuit can be shown in FIG. 12 . At this time, V h is 1/2Vi1.
在T/2至T的时间段内，各个开关管的状态可以如图13所示。其中，开关管S3和S4导通，开关管S1和S2断开。In the time period from T/2 to T, the states of each switch tube may be as shown in FIG. 13 . Among them, the switch tubes S3 and S4 are turned on, and the switch tubes S1 and S2 are turned off.
在此情况下，开关管S3、开关管S4、Cr、Lr和Lm构成通路，等效电路可以如图14所示。由于第一电容呈现断路、且第一H桥电路输出端与输入端12之间直接连接，Vh＝0。In this case, the switch tube S3, the switch tube S4, Cr, Lr and Lm form a path, and the equivalent circuit can be shown in FIG. 14 . Since the first capacitor is disconnected and the output terminal of the first H-bridge circuit is directly connected to the input terminal 12 , Vh=0.
在T至T3/2的时间段内，各个开关管的状态可以如图15所示。其中，开关管S2和S4导通，开关管S1和S3断开。In the time period from T to T3/2, the states of each switch tube may be as shown in FIG. 15 . Among them, the switch tubes S2 and S4 are turned on, and the switch tubes S1 and S3 are turned off.
在此情况下，开关管S4、Cr、开关管S2、Lr和Lm构成通路，等效电路可以如图16所示，此时电容C1放电，由于在0至T/2的时间段内，C1两端已经充电至1/2Vi1，因此，V h为1/2Vi1，这里不做重复介绍。 In this case, the switches S4, Cr, S2, Lr, and Lm form a path, and the equivalent circuit can be shown in Figure 16. At this time, the capacitor C1 discharges, because in the time period from 0 to T/2, C1 Both ends have been charged to 1/2Vi1, therefore, V h is 1/2Vi1, which will not be repeated here.
在3/2T至2T的时间段内，各个开关管的状态可以如图13所示。其中，开关管S1和S2导通，开关管S3和S4断开。In the time period from 3/2T to 2T, the state of each switch tube may be as shown in FIG. 13 . Among them, the switch tubes S1 and S2 are turned on, and the switch tubes S3 and S4 are turned off.
在此情况下，开关管S3、开关管S4、Cr、Lr和Lm构成通路，等效电路可以如图14所示。由于第一H桥电路输出端与输入端12之间直接连接，因此，Vh为0。In this case, the switch tube S3, the switch tube S4, Cr, Lr and Lm form a path, and the equivalent circuit can be shown in FIG. 14 . Since the output terminal of the first H-bridge circuit is directly connected to the input terminal 12 , Vh is zero.
需要指出的是，开关管在使用上述图10所示的驱动信号驱动开关管S1、S2、S3和S4时，交流电的两个周期内逆变电路的输出电压均在0至1/2Vi1之间转换，则逆变电路输出电压的峰峰值为Vi1/2，带入公式五和公式六，得到此时LLC谐振转换单元401的变比N1为4。It should be pointed out that when the switching transistors use the driving signal shown in FIG. 10 to drive the switching transistors S1, S2, S3 and S4, the output voltage of the inverter circuit in two cycles of the alternating current is between 0 and 1/2Vi1 After conversion, the peak-to-peak value of the output voltage of the inverter circuit is Vi1/2, and into formula 5 and formula 6, it is obtained that the transformation ratio N1 of the LLC resonance conversion unit 401 is 4 at this time.
需要说明的是，此时开关管按照②①③①的顺序进行一次切换，在开关管的每一个切换周期内，输出两个周期的交流电，即开关管的开关周期为谐振电路的谐振周期的两倍。It should be noted that, at this time, the switch is switched in the order of ②①③①. In each switching period of the switch, two cycles of alternating current are output, that is, the switching period of the switch is twice the resonant period of the resonant circuit.
第二种实现方式：第一变比N1为2。The second implementation mode: the first transformation ratio N1 is 2.
假设LLC谐振转换单元中的各个开关管皆为高电压导通，低电压断开。在控制器403为LLC谐振转换单元401中的各个开关管提供如图17所示的驱动信号时，第一变比N1为2。其中，控制器按照状态④①的顺序发送驱动信号，从而控制开关管进行状态切换。It is assumed that each switch in the LLC resonant conversion unit is turned on at high voltage and turned off at low voltage. When the controller 403 provides the drive signals as shown in FIG. 17 for each switch tube in the LLC resonant conversion unit 401 , the first transformation ratio N1 is 2. Among them, the controller sends drive signals in the order of states ④①, thereby controlling the switch tube to switch states.
在0至T/2的时间段内，各个开关管的状态可以如图18所示。其中，开关管S1和开关管S2导通，开关管S3和S4断开。In the time period from 0 to T/2, the state of each switch tube can be as shown in FIG. 18 . The switch S1 and the switch S2 are turned on, and the switches S3 and S4 are turned off.
在此情况下，开关管S1、开关管S2、Cr、Lr和Lm构成通路，等效电路可以如图19所示，由于C1并不进行充电，且第一H桥电路跨接在输入端11和12之间，因此，Vh＝Vi1。In this case, the switch S1, the switch S2, Cr, Lr and Lm form a path, and the equivalent circuit can be shown in Figure 19. Since C1 does not charge, and the first H-bridge circuit is connected across the input terminal 11 and 12, therefore, Vh=Vi1.
在T/2至T的时间段内，各个开关管的状态可以如图13所示。其中，开关管S3和S4导通，开关管S1和S2断开。In the time period from T/2 to T, the states of each switch tube may be as shown in FIG. 13 . Among them, the switch tubes S3 and S4 are turned on, and the switch tubes S1 and S2 are turned off.
此情况下，开关管S3、开关管S4、Cr、Lr和Lm构成通路，等效电路可以如图14所示。由于第一电容呈现断路、且第一H桥电路输出端与输入端12之间直接连接，Vh＝0。In this case, the switch tube S3, the switch tube S4, Cr, Lr, and Lm form a path, and the equivalent circuit can be as shown in FIG. 14 . Since the first capacitor is disconnected and the output terminal of the first H-bridge circuit is directly connected to the input terminal 12 , Vh=0.
需要指出的是，开关管在使用上述图17所示的驱动信号驱动开关管S1、S2、S3和S4时，在交流电的整个周期内，逆变电路的输出电压均在0至Vi1之间转换，则逆变电路输出电压的峰峰值为Vi1，带入公式五和公式六，得到此时LLC谐振转换单元401的变比为2。It should be pointed out that when the switching transistors use the driving signal shown in FIG. 17 to drive the switching transistors S1, S2, S3 and S4, the output voltage of the inverter circuit is converted between 0 and Vi1 during the entire cycle of the alternating current. , then the peak-to-peak value of the output voltage of the inverter circuit is Vi1, and into formula 5 and formula 6, it is obtained that the transformation ratio of the LLC resonance conversion unit 401 is 2 at this time.
需要说明的是，此时开关管按照④①的顺序进行一次切换，在开关管的每一个切换周期内，输出一个周期的交流电，即开关管的开关周期与谐振电路的谐振周期相同。It should be noted that at this time, the switch tube is switched in the order of ④①, and in each switching cycle of the switch tube, one cycle of alternating current is output, that is, the switching cycle of the switch tube is the same as the resonant cycle of the resonant circuit.
实际使用时，也可以采用表一中的其他驱动信号的状态进行组合，得到LLC谐振转换单元的其它可调变比，本申请这里一一详细介绍。需要说明的是，在采用其他驱动信号的状态进行组合时，每一个组合中第一电容C1的充放电次数相同。In actual use, the states of other driving signals in Table 1 can also be combined to obtain other adjustable ratios of the LLC resonant conversion unit, which are described in detail here in this application. It should be noted that, when the states of other driving signals are used for combination, the number of times of charging and discharging of the first capacitor C1 in each combination is the same.
需要说明的是，根据负载的类型，整流电路除上述第二H桥电路的结构，还可以采用其他电路结构。例如，整流电路采用带中心抽头的半桥整流电路为负载供电，此时直流转换电路可以采用图20所示的电路结构。It should be noted that, according to the type of the load, in addition to the structure of the second H-bridge circuit described above, the rectifier circuit may also adopt other circuit structures. For example, the rectifier circuit uses a half-bridge rectifier circuit with a center tap to supply power to the load, and the DC conversion circuit can use the circuit structure shown in FIG. 20 at this time.
在一示例中，参见图21所示，为了解决器件成本以及体积，可以使用二极管替换上述第二H桥电路中开关管。In an example, as shown in FIG. 21 , in order to solve the cost and volume of the device, a diode can be used to replace the switch in the second H-bridge circuit.
在一示例中，参见图22所示，谐振电路中谐振电容可以拆分为两个谐振电容C2和C3，用于与谐振电感Lr实现谐振。其中，C1和C2的容值之和为Cr的容值。In an example, as shown in FIG. 22 , the resonant capacitor in the resonant circuit can be split into two resonant capacitors C2 and C3 to achieve resonance with the resonant inductor Lr. Among them, the sum of the capacitances of C1 and C2 is the capacitance of Cr.
LLC谐振转换单元的示例二：Example 2 of the LLC resonant conversion unit:
本申请实施例提供的一种直流转换器，如图23所示。其中，LLC谐振转换单元401中 逆变电路主要包括第一开关管S1、第二开关管S2、由N个第一转换开关管、N个第二转换开关管和N个飞跨电容组成的飞跨电容型多电平半桥逆变电路。谐振电路主要包括谐振电感Lr和谐振电容Cr。变压器原边绕组与谐振电感Lr和谐振电容Cr串联，变压器副边绕组与由H桥组成的整流电路连接。其中，H桥电路主要包括开关管S3、S4、S5和S6。N为大于1的整数。A DC converter provided by an embodiment of the present application is shown in FIG. 23 . The inverter circuit in the LLC resonant conversion unit 401 mainly includes a first switch tube S1, a second switch tube S2, a flying transistor composed of N first switch tubes, N second switch tubes and N flying capacitors. Transcapacitive multi-level half-bridge inverter circuit. The resonant circuit mainly includes the resonant inductor Lr and the resonant capacitor Cr. The primary winding of the transformer is connected in series with the resonant inductor Lr and the resonant capacitor Cr, and the secondary winding of the transformer is connected with the rectifier circuit composed of the H bridge. Among them, the H-bridge circuit mainly includes switch tubes S3, S4, S5 and S6. N is an integer greater than 1.
其中，第一转换开关管依次串联在输入端11和开关管S1的第一端之间。也即，第i个第一转换开关管Si1的第二端与第i+1个第一转换开关管S(i+1)1的第一端连接，第i个第一转换开关管Si1的第一端与第i-1个第一转换开关管S(i-1)1的第二端连接，i从2依次取值至N。同理，第1个至第N个第二转换开关管依次串联在输入端11和开关管S2的第一端之间。其中，第1个第一转换开关管S11的第一端与输入端11连接，第一个第二转换开关管S12的第一端与输入端12连接。Wherein, the first transfer switch tube is connected in series between the input end 11 and the first end of the switch tube S1 in sequence. That is, the second end of the i-th first transfer switch tube Si1 is connected to the first end of the i+1-th first transfer switch tube S(i+1)1, and the i-th first transfer switch tube Si1 The first end is connected to the second end of the i-1th first transfer switch tube S(i-1)1, and i takes values from 2 to N in sequence. Similarly, the first to the Nth second transfer switch tubes are connected in series between the input end 11 and the first end of the switch tube S2 in sequence. The first end of the first first transfer switch S11 is connected to the input end 11 , and the first end of the first second transfer switch S12 is connected to the input end 12 .
其中，S2的第二端和S1的第二端均谐振电容Cr的一端连接，Cr的另一端与谐振电感Lr的一端连接，Lr的另一端与变压器原边绕组的一端连接，变压器原边绕组的另一端和输入端12连接。Among them, the second end of S2 and the second end of S1 are both connected to one end of the resonant capacitor Cr, the other end of Cr is connected to one end of the resonant inductor Lr, the other end of Lr is connected to one end of the primary winding of the transformer, and the primary winding of the transformer is connected. The other end is connected to the input end 12.
其中，S3和S4串联构成H桥电路的第一桥臂，S5和S6串联构成H桥电路的第二桥臂。也即，S4的第二端与S3的第一端连接，S6的第二端与S5的第一端，S3的第一端分别S5的第一端和变压器副边绕组的一端连接，S4的第二端分别与S6的第二端和变压器副边绕组的另一端连接。具体来说，H桥电路的第一桥臂的中间节点和第二桥臂的中间节点分别与输出端12和输出端14连接。也即，S3的第二端与输出端13连接，S5的第二端与输出端14连接。Among them, S3 and S4 are connected in series to form the first bridge arm of the H bridge circuit, and S5 and S6 are connected in series to form the second bridge arm of the H bridge circuit. That is, the second end of S4 is connected to the first end of S3, the second end of S6 is connected to the first end of S5, and the first end of S3 is respectively connected to the first end of S5 and one end of the secondary winding of the transformer, and the first end of S4 The second ends are respectively connected to the second end of S6 and the other end of the secondary winding of the transformer. Specifically, the middle node of the first bridge arm and the middle node of the second bridge arm of the H-bridge circuit are respectively connected to the output end 12 and the output end 14 . That is, the second end of S3 is connected to the output end 13 , and the second end of S5 is connected to the output end 14 .
逆变电路中的第i个第一转换开关管Si1和第i个第二转换开关管Si2构成一个开关组合，逆变电路中可以包括N个开关组合。其中，每一个开关组合中两个开关管的互补导通。The i-th first transfer switch tube Si1 and the i-th second transfer switch tube Si2 in the inverter circuit form a switch combination, and the inverter circuit may include N switch combinations. Wherein, the complementary conduction of the two switch tubes in each switch combination is conducted.
下面结合图23，以N取值为2为例进行说明。在该情况下，飞跨电容主要包括C1和C2，第一转换开关管S11和S21，以及第二转换开关管S12和S22。In the following, in conjunction with FIG. 23 , description is made by taking the value of N as 2 as an example. In this case, the flying capacitor mainly includes C1 and C2, the first transfer switch tubes S11 and S21, and the second transfer switch tubes S12 and S22.
开关管S21与输出开关管S22属于同一开关组合，S11和S12同属于同一个开关组合，以及S1和S2同属于同一个输出组合。The switch tube S21 and the output switch tube S22 belong to the same switch combination, S11 and S12 both belong to the same switch combination, and S1 and S2 both belong to the same output combination.
图23所示的LLC谐振转换电路中的开关管接收不同的驱动信号时，LLC谐振转换单元中的开关管处于不同的状态、且具有不同的变比。当接收不同驱动信号时，驱动信号与飞跨电容型多电平半桥逆变电路的输出电压对应关系可如表二所示。When the switches in the LLC resonant conversion circuit shown in FIG. 23 receive different driving signals, the switches in the LLC resonant conversion unit are in different states and have different transformation ratios. When receiving different driving signals, the corresponding relationship between the driving signal and the output voltage of the flying capacitor type multi-level half-bridge inverter circuit can be shown in Table 2.
表二Table II
   S11&～S12S11&～S12 S21&～S22S21&～S22 S1&～S2S1&～S2 VC1VC1 VC2 VC2 VhVh
状态①Status① 00 00 00 ---- ---- 00
状态② Status ② 00 00 11 ---- 充电Charge Vi1/3Vi1/3
状态③ Status ③ 00 11 00 充电Charge 放电discharge Vi1/3Vi1/3
状态④ Status④ 00 11 11 充电Charge ---- 2Vi1/32Vi1/3
状态⑤ Status⑤ 11 00 00 放电discharge ---- Vi1/3Vi1/3
状态⑥ Status⑥ 11 00 11 放电discharge 充电Charge 2Vi1/32Vi1/3
状态⑦ Status⑦ 11 11 00 ---- 放电discharge 2Vi1/32Vi1/3
状态⑧ Status ⑧ 11 11 11 ---- ---- 1Vi11Vi1
当图23所示的LLC谐振转换单元采用表二所示的驱动信号驱动飞跨电容型多电平半 桥逆变电路中的开关工作时，LLC谐振转换单元至少具有6、3和2三种可调变比。When the LLC resonant conversion unit shown in FIG. 23 uses the driving signal shown in Table 2 to drive the switches in the flying capacitor type multi-level half-bridge inverter circuit, the LLC resonant conversion unit has at least three types of 6, 3 and 2 Adjustable ratio.
需要说明的是，当上述表二中的S11&～S12的状态为0时，表明开关管S11的断开，开关管S12导通。同理，当上述表二中的S11&～S12的状态为1时，表明开关管S11的导通，开关管S12断开。It should be noted that when the states of S11 & to S12 in the above Table 2 are 0, it indicates that the switch S11 is turned off and the switch S12 is turned on. Similarly, when the state of S11 & ~ S12 in the above Table 2 is 1, it indicates that the switch S11 is turned on and the switch S12 is turned off.
下面结合图23以及表二，对LLC谐振转换单元401的三个电压转换档位下的变比进行详细说明。23 and Table 2, the transformation ratios of the LLC resonant conversion unit 401 in the three voltage conversion gears will be described in detail below.
第一种实现方式：第一变比N1为6。The first implementation method: the first transformation ratio N1 is 6.
假设LLC谐振转换单元中的各个开关管皆为高电压导通，低电压断开。在控制器403为LLC谐振转换单元401中的各个开关管提供如图24所示的驱动信号时，第一变比N1为6。其中，驱动信号按照状态②④③⑦⑤⑥的顺序进行切换。It is assumed that each switch in the LLC resonant conversion unit is turned on at high voltage and turned off at low voltage. When the controller 403 provides the driving signals as shown in FIG. 24 for each switch tube in the LLC resonant conversion unit 401, the first transformation ratio N1 is 6. Among them, the driving signals are switched in the order of states ②④③⑦⑤⑥.
当飞跨电容型多电平半桥逆变电路使用上述图24所示的驱动信号驱动开关时，在交流电的三个周期中，逆变电路输出的交流电的三个周期内逆变电路的输出电压均在2Vi1/3至Vi1/3之间切换，则逆变电路输出电压的峰峰值为Vi1/3，带入公式五和公式六，得到此时LLC谐振转换单元401的变比N1为6。When the flying capacitor type multi-level half-bridge inverter circuit uses the driving signal shown in Figure 24 to drive the switch, in the three cycles of the alternating current, the output of the inverter circuit in the three cycles of the alternating current output by the inverter circuit The voltages are switched between 2Vi1/3 and Vi1/3, then the peak-to-peak value of the output voltage of the inverter circuit is Vi1/3, and the formula 5 and formula 6 are entered to obtain the transformation ratio N1 of the LLC resonant conversion unit 401 at this time as 6 .
需要说明的是，此时开关管按照②④③⑦⑤⑥的顺序进行一次切换，在开关管的每一个切换周期内，输出三个周期的交流电，即开关管的开关周期为谐振电路的谐振周期的三倍。It should be noted that at this time, the switch tube is switched in the order of ②④③⑦⑤⑥, and in each switching cycle of the switch tube, three cycles of alternating current are output, that is, the switching cycle of the switch tube is three times the resonant period of the resonant circuit.
第二种实现方式：第一变比N1为3。The second implementation method: the first transformation ratio N1 is 3.
假设LLC谐振转换单元中的各个开关管皆为高电压导通，低电压断开。在控制器403按照状态④①⑥①⑦①的顺序切换LLC谐振转换单元401中的各个开关管的状态时，LLC谐振转换单元变比为3。It is assumed that each switch in the LLC resonant conversion unit is turned on at high voltage and turned off at low voltage. When the controller 403 switches the states of the respective switches in the LLC resonance conversion unit 401 in the order of states ④①⑥①⑦①, the LLC resonance conversion unit has a transformation ratio of 3.
当飞跨电容型多电平半桥逆变电路使用上述方式驱动信号驱动开关时，在交流电的三个周期中，逆变电路输出的交流电的三个周期内逆变电路的输出电压均在2Vi1/3至0之间切换，则逆变电路输出电压的峰峰值为2Vi1/3，带入公式五和公式六，得到此时LLC谐振转换单元401的变比N1为3。When the flying capacitor type multi-level half-bridge inverter circuit uses the above method to drive the signal to drive the switch, in the three cycles of the alternating current, the output voltage of the inverter circuit in the three cycles of the alternating current output by the inverter circuit is all within 2Vi1 /3 to 0, the peak-to-peak value of the output voltage of the inverter circuit is 2Vi1/3;
需要说明的是，此时开关管按照④①⑥①⑦①的顺序进行一次切换，在开关管的每一个切换周期内，输出三个周期的交流电，即开关管的开关周期为谐振电路的谐振频率周期的三倍。It should be noted that, at this time, the switch is switched in the order of ④①⑥①⑦①. In each switching cycle of the switch, three cycles of alternating current are output, that is, the switching period of the switch is three times the resonant frequency period of the resonant circuit. .
第三种实现方式：第一变比N1为2。The third implementation manner: the first transformation ratio N1 is 2.
假设LLC谐振转换单元中的各个开关管皆为高电压导通，低电压断开。在控制器403按照状态⑧①的顺序切换LLC谐振转换单元401中的各个开关管的状态时，LLC谐振转换单元变比为2。It is assumed that each switch in the LLC resonant conversion unit is turned on at high voltage and turned off at low voltage. When the controller 403 switches the states of the respective switches in the LLC resonance conversion unit 401 in the sequence of states ⑧①, the LLC resonance conversion unit has a transformation ratio of 2.
当飞跨电容型多电平半桥逆变电路使用上述方式的驱动信号驱动开关时，在交流电的整个周期内，逆变电路的输出电压均在0至Vi1之间转换，则逆变电路输出电压的峰峰值为Vi1，带入公式五和公式六，得到此时LLC谐振转换单元401的变比为2。When the flying capacitor type multi-level half-bridge inverter circuit uses the above-mentioned driving signal to drive the switch, the output voltage of the inverter circuit is converted between 0 and Vi1 in the whole cycle of the alternating current, then the inverter circuit outputs The peak-to-peak value of the voltage is Vi1, and into formula 5 and formula 6, it is obtained that the transformation ratio of the LLC resonant conversion unit 401 is 2 at this time.
需要说明的是，此时开关管按照⑧①的顺序进行一次切换，在开关管的每一个切换周期内，输出一个周期的交流电，即开关管的开关周期与谐振电路的谐振频率周期相同。It should be noted that, at this time, the switch tube is switched in the order of ⑧①, and in each switching cycle of the switch tube, one cycle of alternating current is output, that is, the switching cycle of the switch tube is the same as the resonant frequency cycle of the resonant circuit.
需要说明的是，也采用其他状态进行组合，得到多个其它的变比，本申请这里一一详细介绍。其中，用采用其他驱动信号的状态进行组合时，每一个组合中飞跨电容C1和C2的充放电次数相同。It should be noted that other states are also used for combination to obtain a plurality of other transformation ratios, which are described in detail here in this application. Among them, when combining with the state of using other driving signals, the times of charging and discharging of the flying capacitors C1 and C2 in each combination are the same.
实际使用时，为了增加LLC谐振转换单元的变比范围，逆变电路中可以包括第一飞跨电容型多电平半桥逆变电路和第二飞跨电容型多电平半桥逆变电路用于增加LLC谐振转换单元的变比类型。In actual use, in order to increase the transformation ratio range of the LLC resonant conversion unit, the inverter circuit may include a first flying capacitor type multi-level half-bridge inverter circuit and a second flying capacitor type multi-level half-bridge inverter circuit. Ratio type used to increase the LLC resonant conversion unit.
参见图25所示，在第一飞跨电容型多电平半桥逆变电路中，第一转换开关管依次串联在输入端11和开关管S1的第一端之间，第二转换开关管依次串联在输入端12和开关管S2的第一端之间，S1的第二端和S2的第二端均与谐振电路的一端连接。Referring to FIG. 25, in the first flying capacitor type multi-level half-bridge inverter circuit, the first transfer switch tube is connected in series between the input terminal 11 and the first end of the switch tube S1 in sequence, and the second transfer switch tube is connected in series. They are connected in series between the input end 12 and the first end of the switch tube S2 in sequence, and the second end of S1 and the second end of S2 are both connected to one end of the resonant circuit.
在第二飞跨电容型多电平半桥逆变电路中，第一转换开关管依次串联在输入端11和开关管S7的第一端之间，第二转换开关管依次串联在输入端12和开关管S8的第一端之间，S1的第二端和S2的第二端均与谐振电路的另一端连接。In the second flying capacitor type multi-level half-bridge inverter circuit, the first transfer switch is connected in series between the input end 11 and the first end of the switch S7, and the second transfer switch is connected in series with the input end 12. Between the first end of the switch tube S8, the second end of S1 and the second end of S2 are both connected to the other end of the resonant circuit.
其中，利用驱动信号实现改变LLC谐振转换单元401变比的过程如本申请LLC谐振转换单元的示例二的过程相同，本申请这里不做重复介绍。The process of changing the ratio of the LLC resonant conversion unit 401 by using the driving signal is the same as the process of Example 2 of the LLC resonant conversion unit of the present application, which will not be repeated in this application.
本申请实施例中，第一调压电路402也存在多种可能的实现方式。一般来说，在第一调压电路402的效率较低的情况下，第一调压电路可以侧重于精细调节输出电压Vo。In the embodiment of the present application, the first voltage regulating circuit 402 also has various possible implementation manners. Generally speaking, when the efficiency of the first voltage regulating circuit 402 is low, the first voltage regulating circuit may focus on finely regulating the output voltage Vo.
第一调压电路的示例一：Example 1 of the first voltage regulating circuit:
第一调压可以是降压(Buck)电路。示例性的，如图9所示，第一调压电压主要包括开关管SH、开关管SL和电感L1。其中，开关管SH的第一端可以作为第一调压电路的输入端21，与LLC谐振转换电路401的输入端12连接。开关管SH的第二端分别与开关管SL的第一端和第二调节电感L2的一端连接，开关管SL的第二端可以作为输出端24，与输入端22连接，并接地。第二调节电感L2的另一端可以作为输出端23，与LLC谐振转换单元401的输出端13连接。The first voltage regulation may be a Buck circuit. Exemplarily, as shown in FIG. 9 , the first voltage regulation voltage mainly includes a switch tube SH, a switch tube SL and an inductor L1 . The first end of the switch tube SH can be used as the input end 21 of the first voltage regulating circuit, and is connected to the input end 12 of the LLC resonant conversion circuit 401 . The second end of the switch tube SH is respectively connected to the first end of the switch tube SL and one end of the second adjusting inductor L2. The second end of the switch tube SL can be used as the output end 24, connected to the input end 22 and grounded. The other end of the second adjusting inductor L2 can be used as the output end 23 and is connected to the output end 13 of the LLC resonance conversion unit 401 .
其中，当第一调压电路处于连续模式为例，占空比DH与第二变比N2之间满足以下关系：Among them, when the first voltage regulation circuit is in continuous mode as an example, the following relationship is satisfied between the duty cycle DH and the second transformation ratio N2:
Figure PCTCN2021133101-appb-000004
Figure PCTCN2021133101-appb-000004
需要说明的是，所述第一调压电路的处于连续模式时，电感L1长期在储能和释放电能之间切换，即流过电感L1的电流长期处于变化状态。It should be noted that, when the first voltage regulating circuit is in the continuous mode, the inductor L1 switches between energy storage and energy release for a long time, that is, the current flowing through the inductor L1 is in a state of change for a long time.
第一调压电路402的示例二：Example 2 of the first voltage regulation circuit 402:
第一调压电路402也可以是Buck-Boost电路。示例性的，如图26所示，第一调压电路402主要包括开关管Sa、开关管Sb、开关管Sc、开关管Sd和调节电感L1。其中，开关管Sa的第一端可以作为第一调压电路的连接端21，与LLC谐振转换单元401的连接端12连接。开关管Sa的第二端可以分别与开关管Sb的第一端和调节电感L1的一端连接。调节电感L1的另一端分别与开关管Sc的第二端和开关管Sd的第一端连接。开关管Sc的第一端可以作为输出端23与LLC谐振转换单元401的输出端13连接。开关管Sb的第二端和开关管Sd的第二端可以作为输入端22和输出端24接地。The first voltage regulating circuit 402 may also be a Buck-Boost circuit. Exemplarily, as shown in FIG. 26 , the first voltage regulation circuit 402 mainly includes a switch transistor Sa, a switch transistor Sb, a switch transistor Sc, a switch transistor Sd and an adjusting inductor L1. Wherein, the first end of the switch tube Sa can be used as the connection end 21 of the first voltage regulating circuit, and is connected to the connection end 12 of the LLC resonance conversion unit 401 . The second end of the switch tube Sa may be connected to the first end of the switch tube Sb and one end of the adjusting inductor L1, respectively. The other end of the adjusting inductance L1 is respectively connected to the second end of the switch Sc and the first end of the switch Sd. The first end of the switch tube Sc can be connected to the output end 13 of the LLC resonant conversion unit 401 as the output end 23 . The second end of the switch Sb and the second end of the switch Sd can be used as the input end 22 and the output end 24 to be grounded.
第一调压电路402的示例四：Example 4 of the first voltage regulation circuit 402:
第一调压电路402也可以是cuk斩波电路。示例性的，如图27所示，第一调压电路主要包括开关管Sa、开关管Sb、调节电容C2、调节电容C3、调节电感L1和调节电感L2。The first voltage regulating circuit 402 may also be a cuk chopper circuit. Exemplarily, as shown in FIG. 27 , the first voltage regulation circuit mainly includes a switch tube Sa, a switch tube Sb, an adjustment capacitor C2, an adjustment capacitor C3, an adjustment inductance L1 and an adjustment inductance L2.
其中，调节电感L1的一端可以作为第一调压电路的输入端21，与LLC谐振转换单元的输入端12连接。调节电感L1的另一端分别与开关管Sa的第一端和调节电容C2的一端连接。调节电容C2的另一端分别与调节电感L2的一端和开关管Sb的第一端连接。调节电感L2的另一端与调节电容C3的一端连接。调节电容C3的另一端、开关管Sa的第二端和开关管Sb的第二端接地。Wherein, one end of the adjusting inductance L1 can be used as the input end 21 of the first voltage adjusting circuit, and is connected to the input end 12 of the LLC resonance conversion unit. The other end of the adjusting inductance L1 is respectively connected to the first end of the switch Sa and one end of the adjusting capacitor C2. The other end of the adjusting capacitor C2 is respectively connected to one end of the adjusting inductance L2 and the first end of the switch tube Sb. The other end of the adjusting inductance L2 is connected to one end of the adjusting capacitor C3. The other end of the adjustment capacitor C3, the second end of the switch Sa and the second end of the switch Sb are grounded.
需要说明的，前述实施例提供第一调压电路402均为非隔离型具有升压功能或者降压功能的转换电路，实际使用时，第一调压电路402也可以是隔离型具有升压功能或者降压功能的转换电路。其中，第一调压电路402可以是但不限于反激式转换器、正激式转换器、半桥式转换器、全桥式转换器、推挽式转换器、谐振开关式转换器等隔离型转换器。It should be noted that the first voltage regulating circuit 402 provided in the foregoing embodiment is a non-isolated conversion circuit with a boosting function or a bucking function. In actual use, the first voltage regulating circuit 402 may also be an isolated type with a boosting function Or the conversion circuit of the step-down function. Wherein, the first voltage regulating circuit 402 may be, but is not limited to, a flyback converter, a forward converter, a half-bridge converter, a full-bridge converter, a push-pull converter, a resonant switching converter, etc. type converter.
以上示例性示出了直流转换器中LLC谐振转换单元401和第一调压电路402的可能的实现方式。如前所述，采用本申请实施例所提供的直流转换器400，有利于提高直流转换器的效率。The above example shows possible implementations of the LLC resonant conversion unit 401 and the first voltage regulation circuit 402 in the DC converter. As mentioned above, using the DC converter 400 provided by the embodiments of the present application is beneficial to improve the efficiency of the DC converter.
在一种可实现的方式中，若单个LLC谐振转换单元的变比N1远小于目标变比Na时，参见图28所示，此时的谐振转换单元可以N个谐振转换电路的组合。其中，N≧2。In an achievable manner, if the transformation ratio N1 of a single LLC resonance conversion unit is much smaller than the target transformation ratio Na, as shown in FIG. 28 , the resonance conversion unit at this time can be a combination of N resonance conversion circuits. Among them, N≧2.
其中，所述N个LLC谐振转换电路中的每一个LLC谐振转换电路均具有多个电压转换档位。Wherein, each of the N LLC resonant conversion circuits has a plurality of voltage conversion gears.
具体地，所述N个LLC谐振转换电路的输入端串联形成所述输入端11和所述输入端12，所述K个LLC谐振转换电路的输出端并联形成所述输出端13和所述输出端14。Specifically, the input terminals of the N LLC resonant conversion circuits form the input terminal 11 and the input terminal 12 in series, and the output terminals of the K LLC resonant conversion circuits form the output terminal 13 and the output terminal in parallel. end 14.
需要说明的是，每一LLC谐振转换电路的结构可以与图9或图23所示的电路结构相同，其工作原理本申请这里不做重复介绍。It should be noted that the structure of each LLC resonant conversion circuit may be the same as the circuit structure shown in FIG. 9 or FIG. 23 , and the working principle thereof will not be described repeatedly in this application.
具体实现时，若采用图28所示的LLC谐振转换单元为连接的电池供电时，在充电过程中，电池电压升高导致目标变比Na减小，此时实现直流转换器输出的变比等于目标变比Na，本申请实施例提供的直流转换器还包括：多个第三开关管S3、多个第四开关管S4和多个第五开关管S5。In the specific implementation, if the LLC resonant conversion unit shown in Figure 28 is used to supply power to the connected battery, during the charging process, the battery voltage rises and the target transformation ratio Na decreases. At this time, the transformation ratio of the output of the DC converter is equal to For the target transformation ratio Na, the DC converter provided by the embodiment of the present application further includes: a plurality of third switch transistors S3, a plurality of fourth switch transistors S4, and a plurality of fifth switch transistors S5.
参见图29，每一个所述第三开关管S3跨接与相邻两个LLC谐振转换电路的输入端的第一端点之间；每一个所述第四开关管跨接与相邻两个LLC谐振转换电路的输入端的第二端点之间；每一个所述第五开关管的一端与相邻两个LLC谐振转换电路中第一个LLC谐振转换单元输入端的第二端点连接，所述第五开关管的另一端与相邻两个LLC谐振转换电路中第二个LLC谐振转换单元输入端的第一端点连接。Referring to FIG. 29 , each of the third switches S3 is connected across the first terminals of the input ends of two adjacent LLC resonant conversion circuits; each of the fourth switches is connected across two adjacent LLCs between the second end points of the input end of the resonant conversion circuit; one end of each of the fifth switch tubes is connected to the second end point of the input end of the first LLC resonant conversion unit in two adjacent LLC resonant conversion circuits, and the fifth The other end of the switch tube is connected to the first end of the input end of the second LLC resonant conversion unit in two adjacent LLC resonant conversion circuits.
实际使用时，当第三开关管S3和S4导通、且开关管S5断开时，K个LLC谐振转换单元的输入侧并联，输出侧并联。当第三开关管S3和S4断开、且开关管S5导通时，K个LLC谐振转换单元的输入侧串联，输出侧并联。In actual use, when the third switch tubes S3 and S4 are turned on and the switch tube S5 is turned off, the input sides of the K LLC resonant conversion units are connected in parallel, and the output sides are connected in parallel. When the third switch tubes S3 and S4 are turned off and the switch tube S5 is turned on, the input sides of the K LLC resonant conversion units are connected in series, and the output sides are connected in parallel.
需要说明的是，当多个LLC谐振转换电路的输入侧并联、且输出侧并联时，多个LLC谐振转换电路的输入电压相同，为了实现输出目标输出电压Va，输入侧并联的多个LLC谐振转换电路的变比相同。It should be noted that when the input sides of multiple LLC resonant conversion circuits are connected in parallel and the output sides are connected in parallel, the input voltages of the multiple LLC resonant conversion circuits are the same. The transformation ratio of the conversion circuit is the same.
具体实现时，开关管S3、S4和S5的均与控制器403连接，通过403发送的驱动信号实现调整状态。During specific implementation, the switches S3 , S4 and S5 are all connected to the controller 403 , and the adjustment state is realized through the driving signal sent by 403 .
由上述实施例可见，基于本申请实施例所提供的直流转换器400，控制器403可以根据直流转换器的目标变比Na，灵活调节开关管S3、S4和S5，从而调整LLC谐振转换单元401的变比。It can be seen from the above embodiments that, based on the DC converter 400 provided by the embodiments of the present application, the controller 403 can flexibly adjust the switching transistors S3, S4 and S5 according to the target transformation ratio Na of the DC converter, thereby adjusting the LLC resonant conversion unit 401 transformation ratio.
在另一种可实现的方式中，直流转换器还可以包括第二调压电压404。In another implementation manner, the DC converter may further include a second voltage regulation voltage 404 .
参见图30，所述第二调压电路404的输入端分别与所述第一调压电路的输入端和所述LLC谐振转换单元的输入端串联形成所述第一输入端和所述第二输入端，所述第二调压电路的输出端分别与所述第一调压电路的输出端和所述LLC谐振转换电路的输出端并联形成所述第一输出端和所述第二输出端。Referring to FIG. 30 , the input terminals of the second voltage regulating circuit 404 are respectively connected in series with the input terminals of the first voltage regulating circuit and the input terminals of the LLC resonant conversion unit to form the first input terminal and the second input terminal. an input end, the output end of the second voltage regulation circuit is respectively connected in parallel with the output end of the first voltage regulation circuit and the output end of the LLC resonant conversion circuit to form the first output end and the second output end .
具体实现时，第二调压电路可以是LLC谐振转换电路或者其他具有高效率的其他转换电路，用于增加直流转换器的变比范围。In specific implementation, the second voltage regulating circuit may be an LLC resonant conversion circuit or other conversion circuits with high efficiency, for increasing the transformation ratio range of the DC converter.
在上述示例中，直流转换器中LLC谐振转换电路和第一调压电路的输入侧串联，输出侧并联。基于相同的技术构思，还可以将LLC谐振转换电路和第一调压电路的输入侧并联，输出侧串联。In the above example, the LLC resonant conversion circuit in the DC converter is connected in series with the input side of the first voltage regulator circuit, and the output side is connected in parallel. Based on the same technical concept, the input side of the LLC resonant conversion circuit and the first voltage regulating circuit can also be connected in parallel, and the output side can be connected in series.
在此情况下，如图31所示，LLC谐振电路的输入端11可以作为输出端11，LLC谐振转换单元的输出端13可以作为输入端13，LLC谐振转换单元的输出端14可以作为输入端14。类似的，第一调压电路的输出端23可以作为输入端23，第一调压电路的输出端24可以作为输入端24。In this case, as shown in FIG. 31, the input terminal 11 of the LLC resonant circuit can be used as the output terminal 11, the output terminal 13 of the LLC resonant conversion unit can be used as the input terminal 13, and the output terminal 14 of the LLC resonant conversion unit can be used as the input terminal. 14. Similarly, the output terminal 23 of the first voltage regulating circuit can be used as the input terminal 23 , and the output terminal 24 of the first voltage regulating circuit can be used as the input terminal 24 .
也就是说，LLC谐振转换单元的输入侧(输入端13和输入端14)和第一调压电路的输入侧(输入端23和输入端24)并联，LLC谐振转换单元401的输出侧(输出端11和12)和第一调压电路402的输出侧(输出端21和22)串联。That is to say, the input side (input terminal 13 and input terminal 14 ) of the LLC resonant conversion unit and the input side (input terminal 23 and input terminal 24 ) of the first voltage regulating circuit are connected in parallel, and the output side (output terminal 24 ) of the LLC resonant conversion unit 401 is connected in parallel. terminals 11 and 12) and the output side (output terminals 21 and 22) of the first voltage regulating circuit 402 are connected in series.
LLC谐振转换单元的输入端13和输入端14可以接收输入电压Vi，LLC谐振转换单元401的输出端11和输出端12可以输出LLC谐振转换单元的输出电压Vo1。第一调压电路402的输入端23和输入端24可以接收直流转换器的输入电压Vi，第一调压电路的输出端21和输出端22可以输出第一调压电路的输出电压Vo2。其中，输出端11与输出端22之间的电压即为直流转换器的输出电压Vo，Vo＝Vo1+Vo2。The input terminal 13 and the input terminal 14 of the LLC resonance conversion unit may receive the input voltage Vi, and the output terminal 11 and the output terminal 12 of the LLC resonance conversion unit 401 may output the output voltage Vo1 of the LLC resonance conversion unit. The input terminal 23 and the input terminal 24 of the first voltage regulating circuit 402 can receive the input voltage Vi of the DC converter, and the output terminal 21 and the output terminal 22 of the first voltage regulating circuit can output the output voltage Vo2 of the first voltage regulating circuit. The voltage between the output terminal 11 and the output terminal 22 is the output voltage Vo of the DC converter, and Vo=Vo1+Vo2.
需要指出的是，当直流转换器的输入侧并联，输出侧串联时，直流转换器为升压电路。在此情况下，第一变比N1可以理解为输出电压Vo1与输入电压Vi之间的比值，即N1＝Vo1/Vi。第二变比N2同理，可以表示为N2＝Vo2/Vi。It should be pointed out that when the input side of the DC converter is connected in parallel and the output side is connected in series, the DC converter is a boost circuit. In this case, the first transformation ratio N1 can be understood as the ratio between the output voltage Vo1 and the input voltage Vi, that is, N1=Vo1/Vi. Similarly, the second transformation ratio N2 can be expressed as N2=Vo2/Vi.
需要指出的是，当本申请实施例所提供的直流转换器作为升压电路时，LLC谐振转换单元和第一调压电路同样可以采用本申请实施例所提供的以上任意示例，具体不再赘述。It should be pointed out that when the DC converter provided by the embodiment of the present application is used as a boost circuit, the LLC resonant conversion unit and the first voltage regulating circuit can also use any of the above examples provided by the embodiment of the present application, and details are not repeated here. .
为了进一步提高直流转换器的效率，在一种可能的实现方式中，在LLC谐振转换单元的效率大于第一调压电路的效率时，LLC谐振转换单元的Vo1大于第二输出电压Vo2。具体分析与图4所示的直流转换器同理，对此不再赘述。In order to further improve the efficiency of the DC converter, in a possible implementation manner, when the efficiency of the LLC resonant conversion unit is greater than that of the first voltage regulating circuit, Vo1 of the LLC resonant conversion unit is greater than the second output voltage Vo2. The specific analysis is the same as that of the DC converter shown in FIG. 4 , and will not be repeated here.
其中，LLC谐振转换单元和第一调压电路的结构可参见前述实施例，本申请这里不做详细介绍。The structures of the LLC resonant conversion unit and the first voltage regulating circuit may refer to the foregoing embodiments, which will not be described in detail in this application.
在一种可能的实现方式中，直流转换器还可以包括控制器，该控制器可以用于控制LLC谐振转换单元将直流转换器的输入电压转换为第一输出电压，控制调压电路将直流转换器的输入电压转换为第二输出电压；以及调整LLC谐振转换单元的电压转换档位。In a possible implementation manner, the DC converter may further include a controller, and the controller may be used to control the LLC resonant conversion unit to convert the input voltage of the DC converter into the first output voltage, and control the voltage regulating circuit to convert the DC to DC The input voltage of the converter is converted into a second output voltage; and the voltage conversion gear of the LLC resonant conversion unit is adjusted.
基于相同的技术构思，本申请实施例还提供一种转换***。该转换***可以包括前述直流转换器和控制器。Based on the same technical idea, the embodiments of the present application also provide a conversion system. The conversion system may include the aforementioned DC converter and controller.
其中，所述直流转换器包括LLC谐振转换单元和第一调压电路，所述LLC谐振转换单元具有多个电压转换档位，所述LLC谐振转换单元包括第一输入端、第二输入端、第一输出端和第二输出端，所述第一调压电路包括第二输入端、第三输入端、第三输出端和第四输出端。其中，LLC谐振转换单元包括逆变电路、谐振电路、变压器和整流电路。Wherein, the DC converter includes an LLC resonant conversion unit and a first voltage regulation circuit, the LLC resonant conversion unit has a plurality of voltage conversion gears, and the LLC resonant conversion unit includes a first input end, a second input end, A first output end and a second output end, the first voltage regulating circuit includes a second input end, a third input end, a third output end and a fourth output end. Wherein, the LLC resonance conversion unit includes an inverter circuit, a resonance circuit, a transformer and a rectifier circuit.
具体地，第二输入端与第三输入端连接，第一输出端与第三输出端连接，第二输出端与第四输出端连接。Specifically, the second input terminal is connected to the third input terminal, the first output terminal is connected to the third output terminal, and the second output terminal is connected to the fourth output terminal.
具体地，所述控制器分别与所述LLC谐振转换单元和所述第一调压电路连接，所述控制器用于：控制所述LLC谐振转换单元将通过所述第一输入端和所述第二输入端接收到的第一输入电压转换为所述转换***的输出电压，并通过所述第一输出端和所述第二输出端输出所述直流转换器的输出电压；控制所述第一调压电路将通过所述第三输入端和所述第四输入端接收到的第二输入电压转换为所述转换***的输出电压，并通过所述第三输出端和所述第四输出端输出所述直流转换器的输出电压，所述直流转换器的总输入电压包括所述第一输入电压和所述第二输入电压。Specifically, the controller is respectively connected to the LLC resonant conversion unit and the first voltage regulation circuit, and the controller is configured to: control the LLC resonant conversion unit to pass the first input terminal and the first voltage regulator circuit. The first input voltage received by the two input terminals is converted into the output voltage of the conversion system, and the output voltage of the DC converter is output through the first output terminal and the second output terminal; controlling the first output terminal The voltage regulating circuit converts the second input voltage received through the third input terminal and the fourth input terminal into the output voltage of the conversion system, and passes the third output terminal and the fourth output terminal The output voltage of the DC converter is output, and the total input voltage of the DC converter includes the first input voltage and the second input voltage.
需要说明的，直流转换器的具体电路结构可参见前述实施例，本申请这里不做详细介绍。It should be noted that, for the specific circuit structure of the DC converter, reference may be made to the foregoing embodiments, which will not be described in detail in this application.
基于相同的构思，本申请实施例还提供了一种电子设备，该电子设备可以包括电源和前述直流转换器。Based on the same concept, the embodiments of the present application also provide an electronic device, which may include a power supply and the aforementioned DC converter.
其中，直流转换器可以与电源连接，并将电源输出的电压转换为负载的供电电压。The DC converter can be connected to the power supply and convert the voltage output by the power supply into the supply voltage of the load.
其中，该电源可以是但不限于电池或车载电源。Wherein, the power source may be, but not limited to, a battery or a vehicle power source.
可选地，该电子设备可以是开关电源，该开关电源分别与电池和可以与负载连接。开关电源可以接收电池提供的电池电压，并将电池电压转换为负载的工作电压后，输出给负载。Optionally, the electronic device may be a switching power supply, which is connected to the battery and to the load, respectively. The switching power supply can receive the battery voltage provided by the battery, convert the battery voltage into the working voltage of the load, and output it to the load.
可选地，该电子设备可以是车载充电器，该电子设备可以与用电设备连接。直流转换器可以接收车载电源提供的电压，并将车载电源输出的电压转换为用电设备的供电电压后，输出给用电设备。Optionally, the electronic device can be a car charger, and the electronic device can be connected to the electrical device. The DC converter can receive the voltage provided by the vehicle power supply, convert the voltage output by the vehicle power supply into the power supply voltage of the electrical equipment, and output it to the electrical equipment.
显然，本领域的技术人员可以对本申请进行各种改动和变型而不脱离本申请的精神和范围。这样，倘若本申请的这些修改和变型属于本申请权利要求及其等同技术的范围之内，则本申请也意图包含这些改动和变型在内。Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims (17)

  1. 一种直流转换器，其特征在于，包括LLC谐振转换单元和第一调压电路，所述LLC谐振转换单元包括第一输入端(11)、第二输入端(12)、第一输出端(13)和第二输出端(14)，所述第一调压电路包括第三输入端(21)、第四输入端(22)、第三输出端(23)和第四输出端；所述第二输入端与所述第三输入端连接，所述第一输出端与所述第三输出端连接，所述第二输出端与所述第四输出端连接，所述LLC谐振转换单元具有多个电压转换档；其中：所述LLC谐振转换单元包括：逆变电路、谐振电路、变压器和整流电路；A DC converter, characterized in that it comprises an LLC resonant conversion unit and a first voltage regulating circuit, the LLC resonant conversion unit comprising a first input end (11), a second input end (12), a first output end ( 13) and a second output end (14), the first voltage regulating circuit includes a third input end (21), a fourth input end (22), a third output end (23) and a fourth output end; the The second input terminal is connected to the third input terminal, the first output terminal is connected to the third output terminal, the second output terminal is connected to the fourth output terminal, and the LLC resonance conversion unit has A plurality of voltage conversion gears; wherein: the LLC resonance conversion unit includes: an inverter circuit, a resonance circuit, a transformer and a rectifier circuit;
    所述逆变电路用于将通过所述第一输入端和所述第二输入端接收的第一输入电压(Vi1)转换为交流电压，将所述交流电压通过所述谐振电路和所述变压器传输给所述整流电路，所述整流电路将所述变压器输出的交流电压转换为所述直流转换器的输出电压(Vo)，并通过所述第一输出端(13)和所述第二输出端(14)输出所述直流转换器的输出电压；The inverter circuit is configured to convert the first input voltage (Vi1) received through the first input terminal and the second input terminal into an AC voltage, and pass the AC voltage through the resonant circuit and the transformer It is transmitted to the rectifier circuit, and the rectifier circuit converts the AC voltage output by the transformer into the output voltage (Vo) of the DC converter, and passes through the first output terminal (13) and the second output The terminal (14) outputs the output voltage of the DC converter;
    所述第一调压电路用于将通过所述第三输入端(21)和所述第四输入端(22)接收到的第二输入电压(Vi2)转换为所述直流转换器的输出电压(Vo)，并通过所述第三输出端和所述第四输出端输出所述直流转换器的输出电压，所述转换电路的总输入电压(Vi)包括所述第一输入电压和所述第二输入电压。The first voltage regulating circuit is used for converting the second input voltage (Vi2) received through the third input terminal (21) and the fourth input terminal (22) into the output voltage of the DC converter (Vo), and the output voltage of the DC converter is output through the third output terminal and the fourth output terminal, and the total input voltage (Vi) of the conversion circuit includes the first input voltage and the second input voltage.
  2. 如权利要求1所述的直流转换器，其特征在于，所述LLC谐振转换单元处于所述多个电压转换档位中的任一电压转换档位时，所述逆变电路输出的交流电压的周期与所述谐振电路的谐振周期相同、且LLC谐振转换单元的输出电压大于零。The DC converter according to claim 1, wherein when the LLC resonant conversion unit is in any voltage conversion gear of the plurality of voltage conversion gears, the AC voltage output by the inverter circuit has a The period is the same as the resonance period of the resonance circuit, and the output voltage of the LLC resonance conversion unit is greater than zero.
  3. 如权利要求1或2所述的直流转换器，其特征在于，所述LLC谐振转换单元的电压转换效率大于所述第一调压电路的电压转换效率，所述LLC谐振转换单元的电压转换效率为所述LLC谐振转换单元的输出功率与所述LLC谐振转换单元的输入功率的比值，所述第一调压电路的电压转换效率为所述第一调压电路的输出功率与所述第一调压电路的输入功率的比值。The DC converter according to claim 1 or 2, wherein the voltage conversion efficiency of the LLC resonant conversion unit is greater than the voltage conversion efficiency of the first voltage regulating circuit, and the voltage conversion efficiency of the LLC resonant conversion unit is the ratio of the output power of the LLC resonant conversion unit to the input power of the LLC resonant conversion unit, and the voltage conversion efficiency of the first voltage regulation circuit is the output power of the first voltage regulation circuit and the first voltage conversion efficiency. The ratio of the input power of the voltage regulator circuit.
  4. 如权利要求2所述的直流转换器，其特征在于，所述直流转换器还包括：控制器；The DC converter of claim 2, wherein the DC converter further comprises: a controller;
    所述控制器用于控制所述LLC谐振转换单元将所述第一输入电压转换为所述直流转换器的输出电压，控制所述第一调压电路将所述第二输入电压转换为所述直流转换器的输出电压；以及The controller is configured to control the LLC resonant conversion unit to convert the first input voltage into an output voltage of the DC converter, and control the first voltage regulation circuit to convert the second input voltage to the DC the output voltage of the converter; and
    根据所述直流转换器的目标变比，调整所述LLC谐振转换单元的电压转换档位；所述目标变比为所述总输入电压和所述直流转换器的目标输出电压之间的比值。The voltage conversion gear of the LLC resonant conversion unit is adjusted according to the target transformation ratio of the DC converter; the target transformation ratio is the ratio between the total input voltage and the target output voltage of the DC converter.
  5. 如权利要求1-4中任一项所述的直流转换器，其特征在于，The DC converter according to any one of claims 1-4, characterized in that,
    所述逆变电路的两个输入端分别形成所述第一输入端和所述第二输入端，所述逆变电路的一个输出端与所述谐振电路一端连接，所述逆变电路的另一个输出端与所述变压器原边绕组的一端连接；The two input ends of the inverter circuit respectively form the first input end and the second input end, one output end of the inverter circuit is connected to one end of the resonant circuit, and the other end of the inverter circuit is connected to one end of the resonant circuit. an output end is connected to one end of the primary winding of the transformer;
    所述谐振电路的另一端与所述变压器原边绕组的另一端连接；The other end of the resonant circuit is connected to the other end of the primary winding of the transformer;
    所述变压器副边绕组的两端分别与所述整流电路的两个输入端连接；Two ends of the secondary winding of the transformer are respectively connected to the two input ends of the rectifier circuit;
    所述整流电路的两个输出端分别形成所述第一输出端和所述第二输出端；The two output ends of the rectifier circuit respectively form the first output end and the second output end;
    所述逆变电路具有多个电压转换比，所述多个电压转换比与所述LLC谐振转换单元的多个电压转换档位一对一。The inverter circuit has a plurality of voltage conversion ratios, and the plurality of voltage conversion ratios are one-to-one with a plurality of voltage conversion gears of the LLC resonance conversion unit.
  6. 如权利要求1-5中任一项所述的直流转换器，其特征在于，所述逆变电路包括：H 桥电路和第一电容；The DC converter according to any one of claims 1-5, wherein the inverter circuit comprises: an H-bridge circuit and a first capacitor;
    所述H桥电路的第一桥臂的第一端形成所述第一输入端，所述第一桥臂的第二端与所述谐振电路的一端连接，所述H桥电路的第二桥臂的第一端形成所述第二输入端，所述第二桥臂的第一端形成所述第二输入端，所述第二桥臂的第二端与所述第一桥臂的第二端连接，所述H桥电路用于接收第一驱动信号，并根据所述第一驱动信号，调整所述LLC谐振转换单元的电压转换档位；The first end of the first bridge arm of the H-bridge circuit forms the first input end, the second end of the first bridge arm is connected to one end of the resonant circuit, and the second bridge of the H-bridge circuit The first end of the arm forms the second input end, the first end of the second bridge arm forms the second input end, and the second end of the second bridge arm is connected to the first end of the first bridge arm. The two terminals are connected, and the H-bridge circuit is used for receiving a first driving signal, and adjusting the voltage conversion gear of the LLC resonance conversion unit according to the first driving signal;
    所述第一电容跨接在所述第一桥臂的中间节点和所述第二桥臂的中间节点之间。The first capacitor is connected across the middle node of the first bridge arm and the middle node of the second bridge arm.
  7. 如权利要求1-6中任一项所述的直流转换器，其特征在于，所述逆变电路包括：飞跨电容型多电平半桥逆变电路、第一开关管和第二开关管；The DC converter according to any one of claims 1-6, wherein the inverter circuit comprises: a flying capacitor type multi-level half-bridge inverter circuit, a first switch tube and a second switch tube ;
    所述飞跨电容型多电平半桥逆变电路的第一输入端形成所述第一输入端，所述飞跨电容型多电平逆变电路的第二输入端形成所述第二输入端，所述飞跨电容型多电平半桥逆变电路的第一输出端与所述第一开关管的第一端连接，所述飞跨电容型多电平半桥逆变电路的第二输出端与所述第二开关管的第一端连接，所述飞跨电容型多电平半桥逆变电路用于接收第二驱动信号，并根据所述第二驱动信号，调整所述LLC谐振转换单元的电压转换档位；The first input terminal of the flying capacitor type multilevel half-bridge inverter circuit forms the first input terminal, and the second input terminal of the flying capacitor type multilevel inverter circuit forms the second input terminal, the first output terminal of the flying capacitor type multi-level half-bridge inverter circuit is connected to the first terminal of the first switch tube, and the first output terminal of the flying capacitor type multi-level half-bridge inverter circuit The two output ends are connected to the first end of the second switch tube, and the flying capacitor type multi-level half-bridge inverter circuit is used for receiving a second driving signal and adjusting the The voltage conversion gear of the LLC resonance conversion unit;
    所述第一开关管的第二端与所述谐振电路的一端连接；The second end of the first switch tube is connected to one end of the resonant circuit;
    所述第二开关管的第二端与所述第一开关管的第二端连接。The second end of the second switch tube is connected to the second end of the first switch tube.
  8. 如权利要求1-7中任一项所述的直流转换器，其特征在于，所述LLC谐振转换单元包括N个LLC谐振转换电路；其中，所述N个LLC谐振转换电路中的每一个LLC谐振转换电路均具有多个电压转换档位：N是大于或等于2的整数；The DC converter according to any one of claims 1-7, wherein the LLC resonant conversion unit comprises N LLC resonant conversion circuits; wherein, each LLC in the N LLC resonant conversion circuits Resonant conversion circuits all have multiple voltage conversion gears: N is an integer greater than or equal to 2;
    所述N个LLC谐振转换电路的输入端串联形成所述第一输入端和所述第二输入端，所述N个LLC谐振转换电路的输出端并联形成所述第一输出端和所述第二输出端。The input terminals of the N LLC resonant conversion circuits are connected in series to form the first input terminal and the second input terminal, and the output terminals of the N LLC resonant conversion circuits are connected in parallel to form the first output terminal and the second input terminal. Two output terminals.
  9. 如权利要求8所述的直流转换器，其特征在于，还包括：多个第三开关管、多个第四开关管和多个第五开关管；The DC converter of claim 8, further comprising: a plurality of third switch tubes, a plurality of fourth switch tubes and a plurality of fifth switch tubes;
    每一个所述第三开关管跨接在相邻两个LLC谐振转换电路的输入端的第一端点之间，所述第一端点为所述LLC谐振转换电路接收高电平的一端；Each of the third switching transistors is connected across the first terminals of the input terminals of two adjacent LLC resonant conversion circuits, and the first terminal is the end of the LLC resonant conversion circuit that receives a high level;
    每一个所述第四开关管跨接在相邻两个LLC谐振转换电路的输入端的第二端点之间，所述第二端点为所述LLC谐振转换电路接收低电平的一端；Each of the fourth switching transistors is connected across second terminals of the input terminals of two adjacent LLC resonant conversion circuits, and the second terminal is the end of the LLC resonant conversion circuit that receives a low level;
    每一个所述第五开关管的一端与相邻两个LLC谐振转换电路中第一个LLC谐振转换单元输入端的第二端点连接，所述第五开关管的另一端与相邻两个LLC谐振转换电路中第二个LLC谐振转换单元输入端的第一端点连接。One end of each of the fifth switches is connected to the second end of the input end of the first LLC resonant conversion unit in two adjacent LLC resonant conversion circuits, and the other end of the fifth switch is resonated with two adjacent LLCs The first terminal of the input end of the second LLC resonant conversion unit in the conversion circuit is connected.
  10. 如权利要求1-9中任一项所述的直流转换器，其特征在于，所述直流转换器还包括：第二调压电路；The DC converter according to any one of claims 1-9, wherein the DC converter further comprises: a second voltage regulating circuit;
    所述第二调压电路的输入端分别与所述第一调压电路的输入端和所述LLC谐振转换单元的输入端串联形成所述第一输入端和所述第二输入端，所述第二调压电路的输出端分别与所述第一调压电路的输出端和所述LLC谐振转换电路的输出端并联形成所述第一输出端和所述第二输出端。The input end of the second voltage regulating circuit is respectively connected in series with the input end of the first voltage regulating circuit and the input end of the LLC resonant conversion unit to form the first input end and the second input end, and the The output end of the second voltage regulation circuit is respectively connected in parallel with the output end of the first voltage regulation circuit and the output end of the LLC resonant conversion circuit to form the first output end and the second output end.
  11. 如权利要求1-10中任一项所述的直流转换器，其特征在于，所述第一调压电路是Buck电路。The DC converter according to any one of claims 1-10, wherein the first voltage regulating circuit is a Buck circuit.
  12. 一种电子设备，其特征在于，包括电源和如权利要求1至11任一项所述的直流转 换器；An electronic device, characterized in that, comprising a power supply and the DC converter as claimed in any one of claims 1 to 11;
    所述直流转换器与所述电源连接，所述直流转换器用于将所述电源输出的电压转换为负载的供电电压。The DC converter is connected to the power supply, and the DC converter is used for converting the voltage output by the power supply into the supply voltage of the load.
  13. 一种直流转换器的控制方法，应用于直流转换器中，其特征在于，所述直流转换器包括LLC谐振转换单元和第一调压电路，所述LLC谐振转换单元具有多个电压转换档位，所述LLC谐振转换单元包括第一输入端、第二输入端、第一输出端和第二输出端，所述第一调压电路包括第三输入端、第四输入端、第三输出端和第四输出端，所述第二输入端与第一第三输入端连接，所述第一输出端与所述第三输出端连接，所述第二输出端与所述第四输出端连接，包括：A control method for a DC converter, which is applied to the DC converter, wherein the DC converter comprises an LLC resonance conversion unit and a first voltage regulating circuit, and the LLC resonance conversion unit has a plurality of voltage conversion gears , the LLC resonant conversion unit includes a first input end, a second input end, a first output end and a second output end, and the first voltage regulating circuit includes a third input end, a fourth input end, and a third output end and a fourth output terminal, the second input terminal is connected to the first and third input terminals, the first output terminal is connected to the third output terminal, and the second output terminal is connected to the fourth output terminal ,include:
    计算目标变比，所述目标变比为所述直流转换器输入电压与所述直流转换器的目标输出电压之间的变比；calculating a target transformation ratio, where the target transformation ratio is a transformation ratio between an input voltage of the DC converter and a target output voltage of the DC converter;
    根据目标变比与所述第一调压电路的最小变比，从所述LLC谐振转换单元的多个电压转换档位中确定所述LLC谐振转换单元的第一变比；According to the target transformation ratio and the minimum transformation ratio of the first voltage regulation circuit, the first transformation ratio of the LLC resonance transformation unit is determined from a plurality of voltage transformation gears of the LLC resonance transformation unit;
    根据所述第一变比和所述目标变比确定所述第一调压电路的第二变比。The second transformation ratio of the first voltage regulation circuit is determined according to the first transformation ratio and the target transformation ratio.
  14. 如权利要求13所述的方法，其特征在于，所述根据目标变比与所述调压电路的最小变比，确定所述LLC谐振转换单元的第一变比；The method of claim 13, wherein the first transformation ratio of the LLC resonance conversion unit is determined according to a target transformation ratio and a minimum transformation ratio of the voltage regulating circuit;
    根据所述目标变比与所述第一调压电压的最小变比，确定所述LLC谐振转换电路的电压转换档位的取值范围；determining the value range of the voltage conversion gear of the LLC resonant conversion circuit according to the minimum conversion ratio of the target conversion ratio and the first voltage regulation voltage;
    将所述LLC谐振转换电路的电压转换档位的取值范围内最大的电压转换档位确定为所述第一变比。The largest voltage conversion gear within the value range of the voltage conversion gears of the LLC resonant conversion circuit is determined as the first transformation ratio.
  15. 根据权利要求13或14所述的方法，其特征在于，所述利用所述目标变比和所述第一变比，确定所述第二变比，包括：The method according to claim 13 or 14, wherein the determining the second transformation ratio by using the target transformation ratio and the first transformation ratio comprises:
    计算所述LLC谐振转换电路处于所述第一变比时所述LLC谐振转换单元的目标输入电压；calculating the target input voltage of the LLC resonant conversion unit when the LLC resonant conversion circuit is in the first transformation ratio;
    计算所述直流转换器输入电压与所述目标输入电压的第一电压差；calculating a first voltage difference between the DC converter input voltage and the target input voltage;
    将所述第一电压差与所述直流转换器的输出电压之间的变比确定为所述第二变比。A transformation ratio between the first voltage difference and the output voltage of the DC converter is determined as the second transformation ratio.
  16. 如权利要求13-15中任一项所述的方法，其特征在于，所述方法还包括：控制所述LLC谐振转换单元处于所述第一变比，以及控制所述第一调压电路处于所述第二变比。The method according to any one of claims 13-15, wherein the method further comprises: controlling the LLC resonant conversion unit to be in the first transformation ratio, and controlling the first voltage regulation circuit to be in a the second transformation ratio.
  17. 如权利要求16所述的方法，其特征在于，所述LLC谐振转换单元包括：逆变电路、谐振电路、变压器和整流电路，所述控制所述LLC谐振转换单元处于所述第一变比，包括：The method according to claim 16, wherein the LLC resonance conversion unit comprises: an inverter circuit, a resonance circuit, a transformer and a rectifier circuit, and the LLC resonance conversion unit is controlled to be in the first transformation ratio, include:
    向所述逆变电路发送驱动信号，控制所述LLC谐振转换单元处于所述第一变比；sending a drive signal to the inverter circuit to control the LLC resonance conversion unit to be in the first transformation ratio;
    其中，所述逆变电路接收所述驱动信号后，所述逆变电路输出的交流电压的周期与所述谐振电路的谐振周期相同。Wherein, after the inverter circuit receives the drive signal, the cycle of the AC voltage output by the inverter circuit is the same as the resonant cycle of the resonant circuit.
PCT/CN2021/133101 2020-12-31 2021-11-25 Direct current converter, electronic device, and control method for direct current converter WO2022142898A1 (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115800733A (en) * 2023-01-09 2023-03-14 苏州浪潮智能科技有限公司 Power conversion circuit and power conversion device
CN117424458A (en) * 2023-12-19 2024-01-19 深圳通业科技股份有限公司 Control method, system and controller of power supply conversion circuit
CN117681680A (en) * 2023-12-29 2024-03-12 江阴飞阳电子科技有限公司 Meter module for optimizing battery output efficiency
TWI838996B (en) * 2022-12-01 2024-04-11 國立陽明交通大學 Regulating rectifier apparatus

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI816617B (en) * 2022-12-08 2023-09-21 台達電子工業股份有限公司 Hybrid mode control method

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103346674A (en) * 2013-06-14 2013-10-09 阳光电源股份有限公司 Insulated converter
CN106230268A (en) * 2016-08-31 2016-12-14 中天昱品科技有限公司 A kind of crisscross parallel LLC resonance DC/DC power inverter
CN106385178A (en) * 2016-11-09 2017-02-08 中车株洲电力机车研究所有限公司 LLC resonance converter
US20170353116A1 (en) * 2016-06-07 2017-12-07 Linear Technology Corporation Transformer-based hybrid power converters
CN107546959A (en) * 2016-06-23 2018-01-05 中兴通讯股份有限公司 A kind of Switching Power Supply, electronic equipment and Switching Power Supply control method
CN108900091A (en) * 2018-07-06 2018-11-27 华南理工大学 A kind of topological structure based on LLC resonant converter
CN109698626A (en) * 2018-12-18 2019-04-30 东南大学 A kind of combined type input series and output parallel commutator transformer and its control method suitable for middle straightening stream power distribution network
CN110417101A (en) * 2019-08-02 2019-11-05 矽力杰半导体技术(杭州)有限公司 Battery charger and method for charging batteries

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103346674A (en) * 2013-06-14 2013-10-09 阳光电源股份有限公司 Insulated converter
US20170353116A1 (en) * 2016-06-07 2017-12-07 Linear Technology Corporation Transformer-based hybrid power converters
CN107546959A (en) * 2016-06-23 2018-01-05 中兴通讯股份有限公司 A kind of Switching Power Supply, electronic equipment and Switching Power Supply control method
CN106230268A (en) * 2016-08-31 2016-12-14 中天昱品科技有限公司 A kind of crisscross parallel LLC resonance DC/DC power inverter
CN106385178A (en) * 2016-11-09 2017-02-08 中车株洲电力机车研究所有限公司 LLC resonance converter
CN108900091A (en) * 2018-07-06 2018-11-27 华南理工大学 A kind of topological structure based on LLC resonant converter
CN109698626A (en) * 2018-12-18 2019-04-30 东南大学 A kind of combined type input series and output parallel commutator transformer and its control method suitable for middle straightening stream power distribution network
CN110417101A (en) * 2019-08-02 2019-11-05 矽力杰半导体技术(杭州)有限公司 Battery charger and method for charging batteries

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI838996B (en) * 2022-12-01 2024-04-11 國立陽明交通大學 Regulating rectifier apparatus
CN115800733A (en) * 2023-01-09 2023-03-14 苏州浪潮智能科技有限公司 Power conversion circuit and power conversion device
CN115800733B (en) * 2023-01-09 2023-05-05 苏州浪潮智能科技有限公司 Power conversion circuit and power conversion device
CN117424458A (en) * 2023-12-19 2024-01-19 深圳通业科技股份有限公司 Control method, system and controller of power supply conversion circuit
CN117424458B (en) * 2023-12-19 2024-02-23 深圳通业科技股份有限公司 Control method, system and controller of power supply conversion circuit
CN117681680A (en) * 2023-12-29 2024-03-12 江阴飞阳电子科技有限公司 Meter module for optimizing battery output efficiency

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