CN215072184U - High-voltage discharge circuit and high-voltage system - Google Patents
High-voltage discharge circuit and high-voltage system Download PDFInfo
- Publication number
- CN215072184U CN215072184U CN202121043141.3U CN202121043141U CN215072184U CN 215072184 U CN215072184 U CN 215072184U CN 202121043141 U CN202121043141 U CN 202121043141U CN 215072184 U CN215072184 U CN 215072184U
- Authority
- CN
- China
- Prior art keywords
- circuit
- discharge
- voltage
- resistor
- channel mos
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Inverter Devices (AREA)
- Rectifiers (AREA)
Abstract
The utility model provides a high-voltage discharge circuit and high-voltage system, include: the discharge circuit is connected with the positive electrode of the direct current bus and the negative electrode of the direct current bus and comprises a discharge resistor and a discharge switch tube which are mutually connected in series; the ACDC conversion circuit is connected with the alternating current power grid and the direct current bus and is provided with a bridge arm midpoint; and the first end of the discharge driving circuit is connected with the midpoint of the bridge arm, the second end of the discharge driving circuit is connected with the discharge switch tube, and the discharge driving circuit comprises a voltage division circuit, a voltage filter circuit connected with part of the voltage division circuit in parallel and a voltage stabilizing circuit connected with the voltage filter circuit in parallel and is used for providing a driving signal for the discharge circuit and controlling the discharge time of the discharge circuit. The utility model discloses a high-voltage discharge circuit can control discharge circuit to the time that high-voltage circuit discharged, reduces discharge circuit's loss.
Description
Technical Field
The utility model relates to a high-voltage discharge technique especially relates to a high-voltage discharge circuit.
Background
In the application of the ACDC conversion circuit, based on the requirements of safety regulations, a high-voltage discharge circuit needs to be designed for a rectified direct-current bus capacitor, and when the ACDC conversion circuit is stopped or fails, the voltage of the high-voltage bus capacitor is reduced to be lower than the safety voltage within a set time. The circuit is usually implemented by a discharge network composed of a plurality of resistors with larger resistance values, as shown in fig. 1, the high-voltage circuit 110 is connected to the ACDC conversion circuit 120, and the ACDC conversion circuit 120 is directly connected in parallel with the discharge resistor 130. However, the application of the discharge resistor causes the following problems: when the ACDC conversion circuit 120 is operating normally, the discharging function is not needed, and at this time, the high voltage of the high voltage circuit 110 is directly applied to the two ends of the discharging resistor 130, which may cause unnecessary loss and reduce the operating efficiency of the ACDC conversion circuit.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a high-voltage discharge circuit can control discharge circuit to the time that high-voltage circuit discharged, reduces discharge circuit's loss.
In order to achieve the above object, the present invention provides a high voltage discharge circuit, including:
the discharge circuit is connected with the positive electrode of the direct current bus and the negative electrode of the direct current bus and comprises a discharge resistor and a discharge switch tube which are mutually connected in series;
the ACDC conversion circuit is connected with the alternating current power grid and the direct current bus and is provided with a bridge arm midpoint;
and the discharge driving circuit is connected with the midpoint of the bridge arm and the discharge switch tube, comprises a voltage division circuit, a voltage filter circuit connected with part of the voltage division circuit in parallel and a voltage stabilizing circuit connected with the voltage filter circuit in parallel, and is used for providing a driving signal for the discharge circuit and controlling the discharge time of the discharge circuit.
Optionally, in the high voltage discharge circuit, the voltage dividing circuit includes: the bridge arm comprises a first resistor and a second resistor which are connected in series, wherein the first resistor and the second resistor are connected between the midpoint of the bridge arm and the negative pole of the direct current bus.
Optionally, in the high-voltage discharge circuit, the voltage filtering circuit includes a first capacitor, the first capacitor is connected in parallel with the second resistor, and the first capacitor is connected in series with the first resistor and is connected to the negative electrode of the dc bus.
Optionally, in the high-voltage discharge circuit, the voltage stabilizing circuit includes a first diode, the first diode is connected in parallel with the second resistor, and the first diode is connected in series with the first resistor and is connected to the negative electrode of the dc bus.
Optionally, in the high-voltage discharge circuit, the discharge switching tube includes a first N-channel MOS tube and a second N-channel MOS tube.
Optionally, in the high-voltage discharge circuit, a first end of the first diode is connected to the gate of the first N-channel MOS transistor, a second end of the first diode is connected to the source of the first N-channel MOS transistor, and a drain of the first N-channel MOS transistor is connected to the gate of the second N-channel MOS transistor.
Optionally, in the high-voltage discharge circuit, the discharge driving circuit further includes a dc blocking circuit, and the dc blocking circuit is connected between a midpoint of a bridge arm of the ACDC conversion circuit and the voltage dividing circuit.
Optionally, in the high-voltage discharge circuit, the dc blocking circuit includes a second diode, and the second diode is connected between the midpoint of the bridge arm and the first resistor.
Optionally, in the high voltage discharge circuit, the discharge driving circuit further includes: and one end of the energy storage capacitor is connected with the source electrode of the first N-channel MOS tube, and the other end of the energy storage capacitor is connected with the grid electrode of the first N-channel MOS tube.
The utility model also provides an electric automobile's high-pressure system, include: the high-voltage discharge circuit.
The utility model provides an among the high-voltage discharge circuit, discharge switch can control discharge resistor and discharge, and discharge drive circuit can realize the control to discharge switch automatically according to ACDC converting circuit's operating condition to control discharge resistor's discharge time reduces discharge circuit's loss.
Drawings
FIG. 1 is a schematic diagram of a prior art high voltage discharge circuit;
fig. 2 is a schematic diagram of a high-voltage discharge circuit according to a first embodiment of the present invention;
fig. 3 is a waveform diagram of a gate voltage of a first N-channel MOS transistor according to a first embodiment of the present invention;
fig. 4 is a schematic diagram of a high-voltage discharge circuit according to a second embodiment of the present invention;
fig. 5 is a voltage waveform diagram of a gate level of a first N-channel MOS transistor according to a second embodiment of the present invention;
fig. 6 is a schematic diagram of a high-voltage discharge circuit according to a third embodiment of the present invention;
fig. 7 is a voltage waveform diagram of a gate level of a first N-channel MOS transistor according to a third embodiment of the present invention;
in the figure: 110-high voltage circuit, 120-ACDC conversion circuit, 130-discharge circuit, Q1-first MOS tube, Q2-second MOS tube, Q3-third MOS tube, Q4-fourth MOS tube, R1-first resistor, R2-second resistor, R3-third resistor, R4-fourth resistor, RL-discharge resistor, C1-first capacitor, C2-second capacitor, C3-third capacitor, Cac-differential mode capacitor, D1-first diode, D2-second diode, D3-third diode, Rg-DC bus capacitor, S0-first N channel MOS tube, S1-second N channel MOS tube, D3-third diode, and-fifth resistor.
Detailed Description
The following description of the embodiments of the present invention will be described in more detail with reference to the drawings. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the drawings are in simplified form and are not to precise scale, and are provided for convenience and clarity in order to facilitate the description of the embodiments of the present invention.
In the following, the terms "first," "second," and the like are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances. Similarly, if the method described herein comprises a series of steps, the order in which these steps are presented herein is not necessarily the only order in which these steps may be performed, and some of the described steps may be omitted and/or some other steps not described herein may be added to the method.
Example one
The embodiment of the utility model provides a high-voltage discharge circuit, include:
the discharge circuit is connected with the positive electrode of the direct current bus and the negative electrode of the direct current bus and comprises a discharge resistor and a discharge switch tube which are mutually connected in series;
the ACDC conversion circuit is connected with the alternating current power grid and the direct current bus and is provided with a bridge arm midpoint;
and the discharge driving circuit is connected with the midpoint of the bridge arm and the discharge switch tube, comprises a voltage division circuit, a voltage filter circuit connected with part of the voltage division circuit in parallel and a voltage stabilizing circuit connected with the voltage filter circuit in parallel, and is used for providing a driving signal for the discharge circuit and controlling the discharge time of the discharge circuit.
The ACDC conversion circuit comprises a bridge arm consisting of a plurality of MOS (metal oxide semiconductor) tubes or a plurality of diodes, and the output voltage of the midpoint of the bridge arm is jump voltage; the voltage dividing circuit includes: the ACDC conversion circuit comprises a first resistor and a second resistor which are connected in series, wherein the first resistor and the second resistor are connected between the midpoint of a bridge arm of the ACDC conversion circuit and the negative electrode of a DC bus. The voltage filtering circuit comprises a first capacitor, the first capacitor is connected with a second resistor in parallel, and the first capacitor is connected with the first resistor in series and is connected with the negative electrode of the direct current bus in parallel. The voltage stabilizing circuit comprises a first diode, the first diode is connected with a second resistor in parallel, and the first diode is connected in series with the first resistor and is connected with the negative electrode of the direct current bus. The discharge switch tube is a first N-channel MOS tube and a second N-channel MOS tube. The first end of the first diode is connected with the grid electrode of the first N-channel MOS tube, the second end of the first diode is connected with the source electrode of the first N-channel MOS tube, the drain electrode of the first N-channel MOS tube is connected with the grid electrode of the second N-channel MOS tube, and the drain electrode of the second N-channel MOS tube is communicated with the drain electrode of the first N-channel MOS tube through the fourth resistor. In other embodiments of the present invention, the first N-channel MOS transistor and the second N-channel MOS transistor can be replaced by corresponding N-type triodes.
Specifically, referring to fig. 2 and 3, the circuit of the first embodiment includes: a first end of a high-voltage alternating-current power supply AC is connected with a first end of an inductor L1, a second end of the inductor L1 is connected with a first MOS transistor Q1 and a second MOS transistor Q2, a second end of the high-voltage power supply AC is connected with a third MOS transistor Q3 and a fourth MOS transistor Q4, a bridge arm is composed of the first MOS transistor Q1, the second MOS transistor Q2, the third MOS transistor Q3 and the fourth MOS transistor Q4, a specific connection mode is the prior art, and details are not described herein, and a connection point of the third MOS transistor Q3 and the fourth MOS transistor Q4 is also a point a of a middle point of the bridge arm; the bridge arm midpoint A is further connected with a first end of a first resistor R1, a second end of the first resistor R1 is connected with a first end of a second resistor R2, a second end of the second resistor R2 is connected with a first end of a first capacitor C1, a first end of a second resistor R2, a first end of a first diode D1 is connected with a gate of a first N-channel MOS tube S0, a second end of the second resistor R2 is connected with a source of the first N-channel MOS tube S0, a drain of the first N-channel MOS tube S0 is connected with a gate of a second N-channel MOS tube S1, and a gate of the second N-channel MOS tube S1 is communicated with a drain of the second N-channel MOS tube S1 through a fourth resistor R4; the second end of the first capacitor C1, the second end of the second resistor R2, the second end of the first diode D1 and the source of the second N-channel MOS tube S1 are connected together and are connected with the cathode of the direct current bus; the drain of the second N-channel MOS transistor S1 is connected to the first end of the discharge resistor RL, the third diode D3 is connected in parallel with the fifth resistor Rg, the first end of the parallel connection is connected to the gate of the second N-channel MOS transistor S1, the second end of the parallel connection is connected to the cathode of the dc bus, the second end of the discharge resistor RL is connected to the anode of the dc bus, the dc bus capacitor Cbus is connected between the anode and the cathode of the dc bus, and the dc bus capacitor Cbus is also connected between the second end of the discharge resistor RL and the source of the second N-channel MOS transistor S1.
In the circuit, a modified discharge circuit is formed by a first resistor R1, a second resistor R2, a first capacitor C1, a first diode D1, a first N-channel MOS transistor S0, a second N-channel MOS transistor S1 and a discharge resistor RL. The driving signal of the first N-channel MOS transistor S0 is taken from a point a of a bridge arm of the ACDC conversion circuit, and the first diode D1 is used to ensure that the driving signal does not exceed a maximum voltage that the gate of the first N-channel MOS transistor S0 can bear.
When the ACDC conversion circuit works normally, the voltage from the point A of the bridge arm is divided through the first resistor R1 and the second resistor R2, the amplitude is reduced after the voltage is divided, and then the voltage is filtered through the first capacitor C1 to obtain a direct current voltage signal with the amplitude of about 15-20V, wherein the direct current voltage signal is used as a driving signal of the first N-channel MOS transistor S0. As shown in fig. 3, during the time t is greater than or equal to 0 and less than or equal to 0.01S, the signal is directly applied to the gate of the first N-channel MOS transistor S0, so that the first N-channel MOS transistor S0 is kept turned on, and the second N-channel MOS transistor S1 is kept turned off, therefore, when the ACDC conversion circuit normally operates, the discharge circuit discharges through the discharge resistor RL and the R4 with a resistance value up to several hundred thousand ohms, and since the resistance value of the R4 is very large, the current flowing through the discharge resistor and the R4 is very small, and the generated power loss is very small and negligible.
When the ACDC conversion circuit stops working, the potential at the point a of the bridge arm stops jumping, and under the action of the first resistor R1 and the second resistor R2 connected in series, the potential at the point a decreases, the voltage on the first capacitor C1 is discharged through the second resistor R2, so that the driving voltage of the first N-channel MOS transistor S0 gradually decreases until the first N-channel MOS transistor S0 is cut off, and at this time, the voltage of the dc bus is divided by the discharge resistor RL, the fourth resistor R4, and the fifth resistor Rg, so that the voltage between the gate and the source of the second N-channel MOS transistor S1 reaches its driving level, and the second N-channel MOS transistor S1 is turned on, as shown in the simulation result in fig. 3. At this time, the charge on dc bus capacitor Cbus is discharged through discharge resistor RL.
Example two
The embodiment of the utility model provides a high-voltage discharge circuit, include:
the discharge circuit is connected with the positive electrode of the direct current bus and the negative electrode of the direct current bus and comprises a discharge resistor and a discharge switch tube which are mutually connected in series;
the ACDC conversion circuit is connected with the alternating current power grid and the direct current bus and is provided with a bridge arm midpoint;
and the discharge driving circuit is connected with the midpoint of the bridge arm and the discharge switch tube, comprises a voltage division circuit, a voltage filter circuit connected with part of the voltage division circuit in parallel and a voltage stabilizing circuit connected with the voltage filter circuit in parallel, and is used for providing a driving signal for the discharge circuit and controlling the discharge time of the discharge circuit.
The ACDC conversion circuit comprises a bridge arm consisting of a plurality of MOS (metal oxide semiconductor) tubes or a plurality of diodes, and the output voltage of the midpoint of the bridge arm is jump voltage; the voltage dividing circuit includes: the ACDC conversion circuit comprises a first resistor and a second resistor which are connected in series, wherein the first resistor and the second resistor are connected between the midpoint of a bridge arm of the ACDC conversion circuit and the negative electrode of a DC bus. The voltage filtering circuit comprises a first capacitor, the first capacitor is connected with a second resistor in parallel, and the first capacitor is connected with the first resistor in series and is connected with the negative electrode of the direct current bus in parallel. The voltage stabilizing circuit comprises a first diode, the first diode is connected with a second resistor in parallel, and the first diode is connected with the first resistor in series and is connected with the negative electrode of the direct current bus in parallel. The discharge switch tube is a first N-channel MOS tube and a second N-channel MOS tube. The first end of the first diode is connected with the grid electrode of the first N-channel MOS tube, the second end of the first diode is connected with the source electrode of the first N-channel MOS tube, the drain electrode of the first N-channel MOS tube is connected with the grid electrode of the second N-channel MOS tube, and the drain electrode of the second N-channel MOS tube is communicated with the drain electrode of the first N-channel MOS tube through the fourth resistor. In other embodiments of the present invention, the first N-channel MOS transistor and the second N-channel MOS transistor can be replaced by corresponding N-type triodes. The discharge driving circuit further comprises a blocking circuit, and the blocking circuit is connected between the midpoint of the bridge arm of the ACDC conversion circuit and the voltage division circuit. The blocking circuit comprises a second diode which is connected in series with the rectified voltage and the first resistor. The discharge drive circuit further includes: and the energy storage capacitor and the pull-down resistor are connected with the voltage stabilizing circuit in parallel.
Specifically, referring to fig. 4 and 5, the circuit of the second embodiment includes: a first end of a high-voltage power supply AC is connected with a first end of an inductor L1, a second end of the inductor L1 is connected with a first MOS transistor Q1 and a second MOS transistor Q2, a second end of the high-voltage power supply AC is connected with a third MOS transistor Q3 and a fourth MOS transistor Q4, a bridge arm is composed of the first MOS transistor Q1, the second MOS transistor Q2, the third MOS transistor Q3 and the fourth MOS transistor Q4, a specific connection mode is the prior art, and details are not described herein, and a connection point of the third MOS transistor Q3 and the fourth MOS transistor Q4 is also a point a of a middle point of the bridge arm; the bridge arm midpoint A is further connected with a first end of a second capacitor C2, a second end of a second capacitor C2 is connected with a first end of a first resistor R1, a second end of the first resistor R1 is connected with a first end of a second resistor R2, a second end of a second resistor R2 is connected with a first end of a first capacitor C1, a first end of a second resistor R2, and a first end of a first diode D1 is connected with a gate of a first N-channel MOS tube S0, a second end of the first resistor R2 is connected with a source of a first N-channel MOS tube S0, a drain of the first N-channel MOS tube S0 is connected with a gate of the second N-channel MOS tube S1, a gate of the second N-channel MOS tube S1 is communicated with a source of the second N-channel MOS tube S1 through a fourth resistor R4, and the second capacitor C2 is a blocking capacitor; the second end of the first capacitor C1, the second end of the second resistor R2, the second end of the first diode D1 and the gate of the second N-channel MOS tube S1 are connected and connected together with the cathode of the direct current bus; the third resistor R3 is connected in parallel with the third capacitor C3 and in parallel with the second diode D2, the third resistor R3 is a pull-down resistor, the first end of the third capacitor C3 is further connected to the source of the first N-channel MOS transistor S0, the second end of the third capacitor C3 is further connected to the gate of the first N-channel MOS transistor S0, and the third capacitor C3 is an energy storage capacitor; the source electrode of the second N-channel MOS tube S1 is connected with the first end of the discharge resistor RL, the third diode D3 is connected with the fifth resistor Rg in parallel, the first end after parallel connection is connected with the source electrode of the second N-channel MOS tube S1, the second end is connected with the negative electrode of the direct current bus, the second end of the discharge resistor RL is connected with the positive electrode of the direct current bus, the direct current bus capacitor Cbus is connected between the positive electrode of the direct current bus and the negative electrode of the direct current bus, and meanwhile, the direct current bus capacitor Cbus is also connected between the second end of the discharge resistor RL and the drain electrode of the second N-channel MOS tube S1. Compared with the first embodiment, the second embodiment has more direct current blocking capacitors, energy storage capacitors and pull-down resistors.
Furthermore, in the circuit, a signal of a driving circuit of the second N-channel MOS transistor S1 is also taken from a point a of a bridge arm of the ACDC conversion circuit, the second capacitor C2 is a blocking capacitor, the first resistor R1 and the second resistor R2 are voltage dividing resistors, the third capacitor C3 may select a filter capacitor as an energy storage capacitor, the second diode D2 is a rectifier diode, the third resistor R3 is a pull-down resistor of the energy storage capacitor, the third capacitor C3 is an energy storage filter capacitor after rectification, and the first diode D1 is used to ensure that the driving signal does not exceed a maximum voltage that the gate of the second N-channel MOS transistor S1 can bear.
When the ACDC conversion circuit works normally, the voltage from the point A of the bridge arm is subjected to voltage division through the first resistor R1 and the second resistor R2 after being blocked, the amplitude is reduced after the voltage division, and then the direct current voltage signal with the amplitude of about 15V-20V is obtained after filtering through the first capacitor C1 and is used as a driving signal of the second N-channel MOS transistor S1. As shown in FIG. 5, during the time t is greater than or equal to 0 and less than or equal to 0.01S, the signal is directly applied to the gate of the second N-channel MOS transistor S1 to keep the second N-channel MOS transistor S1 turned off, so that when the ACDC conversion circuit works normally, the discharge circuit is in an off state, no current flows through the discharge resistor RL, and no power loss is generated by the discharge resistor RL.
When the ACDC conversion circuit stops working, the potential of the point a in the bridge arm stops jumping, and under the action of the first resistor R1 and the second resistor R2 connected in series, the potential of the point a decreases, and the voltage on the first capacitor C1 is discharged through the second resistor R2, so that the driving voltage of the second N-channel MOS transistor S1 gradually decreases until the second N-channel MOS transistor S1 is turned on, as shown in the simulation result in fig. 5. At this time, the charge on the dc bus capacitor Cbus is discharged through the discharge resistor RL.
EXAMPLE III
The embodiment of the utility model provides a high-voltage discharge circuit, include: the first end of the discharge circuit is connected with the first end of the high-voltage alternating current circuit, the second end of the discharge circuit is connected with the second end of the high-voltage alternating current circuit, and the discharge circuit comprises a discharge resistor and a discharge switch tube which are connected in series; the bridge arm neutral point is connected with an alternating current power grid and a direct current bus and is provided with a bridge arm neutral point; the first end of the discharge driving circuit is connected with the second end of the ACDC conversion circuit, the second end of the discharge driving circuit is connected with the discharge switch tube, the discharge driving circuit comprises a voltage division circuit, a voltage filtering circuit connected with part of the voltage division circuit in parallel and a voltage stabilizing circuit connected with the voltage filtering circuit in parallel, and the voltage stabilizing circuit is used for providing a driving signal for the discharge circuit and controlling the discharge time of the discharge circuit.
The ACDC conversion circuit comprises a first diode, a second diode and a third diode, wherein the first diode is a rectifying diode; the high-voltage circuit comprises alternating voltage, and the ACDC conversion circuit rectifies the high-voltage circuit and provides rectified voltage for the discharge driving circuit. The voltage dividing circuit includes: the first resistor and the second resistor are connected in series, and the first resistor and the second resistor are connected between the cathode of the rectifier diode and the second end of the alternating voltage. The voltage filtering circuit comprises a first capacitor, and the first capacitor is connected with a second resistor in parallel. The voltage stabilizing circuit comprises a first diode, and the first diode is connected with a second resistor in parallel. The discharge switch tube is a first N-channel MOS tube and a second N-channel MOS tube. The first end of the first diode is connected with the grid electrode of the first N-channel MOS tube, the second end of the first diode is connected with the source electrode of the first N-channel MOS tube, the drain electrode of the first N-channel MOS tube is connected with the grid electrode of the second N-channel MOS tube, and the drain electrode of the second N-channel MOS tube is communicated with the drain electrode of the first N-channel MOS tube through the fourth resistor. In other embodiments of the present invention, the first N-channel MOS transistor and the second N-channel MOS transistor can be replaced by corresponding N-type triodes.
Specifically, referring to fig. 6 and 7, the circuit of the third embodiment includes: a first end of the alternating current voltage AC is connected with a first end of a first diode D1, a second end of a first diode D1 is connected with a first end of a first resistor R1, a second end of the first resistor R1 is connected with a first end of a second resistor R2, a second end of a second resistor R2 is connected with a first end of a first capacitor C1, a first end of a second resistor R2 and a first end of a first diode D1, a first end of a first diode D1 is connected with a gate of a first N-channel MOS S0, a second end of the first diode D2 is connected with a source of a first N-channel MOS S0, a drain of the first N-channel MOS S0 is connected with a gate of a second N-channel MOS S1, and a gate of the second N-channel MOS S1 is communicated with a drain of the second N-channel MOS S1 through a fourth resistor R4; a second end of the first capacitor C1, a second end of the second resistor R2, a second end of the first diode D1 and a source of the second N-channel MOS transistor S1 are connected and connected together with a second end of the alternating voltage AC; the drain of the second N-channel MOS transistor S1 is connected to the first end of the discharge resistor RL, the third diode D3 is connected in parallel with the fifth resistor Rg, the first end of the parallel connection is connected to the gate of the second N-channel MOS transistor S1, the second end of the parallel connection is connected to the second end of the alternating voltage AC, the second end of the discharge resistor RL is connected to the first end of the alternating voltage AC, the differential mode capacitor Cac is connected between the first end and the second end of the alternating voltage, and the differential mode capacitor Cac is also connected between the second end of the discharge resistor RL and the source of the second N-channel MOS transistor S1. Compared with the first embodiment, the third embodiment replaces the ACDC conversion circuit with the ACDC conversion circuit.
In the circuit, signals of a driving circuit of a first N-channel MOS tube S0 are taken from two ends of an alternating current voltage AC, a first diode D1 is a rectifying diode, a first resistor R1 and a second resistor R2 are voltage dividing resistors, a second diode D2 is a voltage stabilizing diode, and a second diode D2 is used for ensuring that the driving signals do not exceed the maximum voltage which can be borne by the grid electrode of the first N-channel MOS tube S0.
When the ACDC conversion circuit works normally, the voltage of the high-voltage power supply is divided by the first resistor R1 and the second resistor R2, the amplitude is reduced after the voltage division, and a direct-current voltage signal is obtained after the voltage is filtered by the first capacitor C1 and is used as a driving signal of the first N-channel MOS transistor S0. As shown in fig. 7, during the time t is greater than or equal to 0 and less than or equal to 10S, the signal is directly applied to the gate of the first N-channel MOS transistor S0, so that the first N-channel MOS transistor S0 is kept turned on, and the second N-channel MOS transistor S1 is kept turned off, therefore, when the ACDC conversion circuit normally operates, the discharge circuit discharges through the discharge resistor RL and the R4 with a resistance value up to several hundred thousand ohms, and since the resistance value of the R4 is very large, the current flowing through the discharge resistor and the R4 is very small, and the generated power loss is very small and negligible.
When the ac voltage is zero, the voltage across the first capacitor C1 is discharged through the second resistor R2, so that the driving voltage of the first N-channel MOS transistor S0 gradually decreases until the first N-channel MOS transistor S0 is turned off, and at this time, the ac voltage is divided by the discharge resistor RL, the fourth resistor R4, and the fifth resistor Rg, so that the voltage between the gate and the source of the second N-channel MOS transistor S1 reaches its driving level, and the second N-channel MOS transistor S1 is turned on, as shown in the simulation result of fig. 7. At this time, the charge on the differential-mode capacitor Cac is discharged through the discharge resistor RL.
The utility model discloses a second N channel MOS pipe S1 'S of three embodiments drive circuit that discharges is accomplished by analog circuit, and this circuit can realize the control to second N channel MOS pipe S1 break-make state according to ACDC converting circuit' S operating condition is automatic, and second N channel MOS pipe S1 is the off-state when ACDC converting circuit during operation promptly, and second N channel MOS pipe S1 is the on-state when alternating voltage is zero. And the Micro Control Unit (MCU) is not required to be relied on for Control. The control is simple, and meanwhile, the risk that the microcontroller fails to discharge due to failure is avoided. The current flowing through the discharge resistor is far smaller than the current flowing when the ACDC conversion circuit stops working when the ACDC conversion circuit works normally, and in the traditional high-voltage discharge circuit, as long as the ACDC conversion circuit starts working, the discharge resistor in the circuit always bears the voltage, flows the current and generates loss. Therefore, after the high-voltage discharge circuit is adopted, the rated working time of the discharge resistor is obviously reduced in the life cycle of the whole product, and the advantage that the resistor with smaller resistance value and lower rated power consumption can be realized to achieve the effect of faster discharge. And the utility model discloses a discharge resistance is parallelly connected or/and the series connection by resistance less in quantity constitutes, has reduced the complexity of circuit.
The embodiment of the utility model provides an electric automobile's high-pressure system is still provided, include, high-pressure discharge circuit. The utility model discloses an electric automobile's high-pressure system is applicable to high voltage direct current converter, for example the energy converter between high-voltage battery and the low-voltage battery, namely high-pressure DCDC converter; products including bridge and bridgeless PFC circuits, such as vehicle chargers, frequency converters, UPSs, etc.; and a motor controller (inverter), a power electronic converter that converts the direct-current voltage of the high-voltage battery into three-phase alternating current for the motor. Even, the utility model discloses an electric automobile's high-pressure system still is applicable to above product and the integrated product of any form integration. Simultaneously, the high voltage discharge circuit of high voltage circuit such as the input of above product, output port and inside direct current generating line all is suitable for the utility model discloses an improved generation high voltage discharge circuit.
To sum up, in the embodiment of the utility model provides an among the high-voltage discharge circuit, discharge switch can control discharge resistance and discharge, and discharge drive circuit can realize the control to discharge switch according to ACDC converting circuit's operating condition is automatic to control discharge resistance's discharge time reduces discharge circuit's loss.
The above description is only for the preferred embodiment of the present invention, and does not limit the present invention. Any technical personnel who belongs to the technical field, in the scope that does not deviate from the technical scheme of the utility model, to the technical scheme and the technical content that the utility model discloses expose do the change such as the equivalent replacement of any form or modification, all belong to the content that does not break away from the technical scheme of the utility model, still belong to within the scope of protection of the utility model.
Claims (10)
1. A high voltage discharge circuit, comprising:
the discharge circuit is connected with the positive electrode of the direct current bus and the negative electrode of the direct current bus and comprises a discharge resistor and a discharge switch tube which are mutually connected in series;
the ACDC conversion circuit is connected with the alternating current power grid and the direct current bus and is provided with a bridge arm midpoint;
and the discharge driving circuit is connected with the midpoint of the bridge arm and the discharge switch tube, comprises a voltage division circuit, a voltage filter circuit connected with part of the voltage division circuit in parallel and a voltage stabilizing circuit connected with the voltage filter circuit in parallel, and is used for providing a driving signal for the discharge circuit and controlling the discharge time of the discharge circuit.
2. The high voltage discharge circuit of claim 1, wherein the voltage divider circuit comprises: the bridge arm comprises a first resistor and a second resistor which are connected in series, wherein the first resistor and the second resistor are connected between the midpoint of the bridge arm and the negative pole of the direct current bus.
3. The high voltage discharge circuit of claim 2 wherein said voltage filtering circuit includes a first capacitor connected in parallel with said second resistor, said first capacitor being connected in series with said first resistor and connected to the negative terminal of said dc bus.
4. The high voltage discharge circuit of claim 2 wherein said voltage regulation circuit includes a first diode connected in parallel with said second resistor, said first diode connected in series with said first resistor and connected to the negative terminal of said dc bus.
5. The high voltage discharge circuit of claim 4, wherein said discharge switch comprises a first N-channel MOS transistor and a second N-channel MOS transistor.
6. The high voltage discharge circuit as claimed in claim 5, wherein the first diode has a first terminal connected to the gate of the first N-channel MOS transistor, a second terminal connected to the source of the first N-channel MOS transistor, and a drain of the first N-channel MOS transistor connected to the gate of the second N-channel MOS transistor.
7. The high voltage discharge circuit of claim 2 wherein said discharge driver circuit further comprises a dc blocking circuit connected between a bridge arm midpoint of said ACDC converter circuit and said voltage divider circuit.
8. The high voltage discharge circuit of claim 7 wherein said dc blocking circuit includes a second diode connected between said bridge leg midpoint and said first resistor.
9. The high voltage discharge circuit of claim 1, wherein the discharge drive circuit further comprises: and one end of the energy storage capacitor is connected with the source electrode of the first N-channel MOS tube, and the other end of the energy storage capacitor is connected with the grid electrode of the first N-channel MOS tube.
10. A high voltage system for an electric vehicle, comprising: a high voltage discharge circuit as claimed in any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121043141.3U CN215072184U (en) | 2021-05-14 | 2021-05-14 | High-voltage discharge circuit and high-voltage system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121043141.3U CN215072184U (en) | 2021-05-14 | 2021-05-14 | High-voltage discharge circuit and high-voltage system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN215072184U true CN215072184U (en) | 2021-12-07 |
Family
ID=79217361
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121043141.3U Active CN215072184U (en) | 2021-05-14 | 2021-05-14 | High-voltage discharge circuit and high-voltage system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN215072184U (en) |
-
2021
- 2021-05-14 CN CN202121043141.3U patent/CN215072184U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7514817B2 (en) | Converting device with power factor correcting and dc/dc converting functions | |
| US10096435B2 (en) | Digitalized double-excitation uninterrupted switching power supply | |
| CN103219878A (en) | Capacitor discharging circuit and power converter | |
| CN102148566B (en) | Boost-type voltage balance converter | |
| US20230208279A1 (en) | Active diode circuit and ac/dc power conversion circuit | |
| CN103647448B (en) | Integrated step-down-flyback type high power factor constant current circuit and device | |
| CN112821761A (en) | Flying capacitor three-level boost circuit | |
| CN101355305B (en) | Multifunctional active clamping structure-changing type double tube positive and negative sharp DC convertor | |
| CN100377481C (en) | Integration converton with three phase power factor correction | |
| CN209072366U (en) | A kind of low inductance value standard is without bridge AC-DC circuit | |
| CN215072184U (en) | High-voltage discharge circuit and high-voltage system | |
| CN109634341B (en) | Compensation type voltage-stabilized power supply with bidirectional APFC | |
| CN217087767U (en) | Ultrahigh-gain DC/DC boost converter | |
| CN202679247U (en) | Switch power supply circuit and set-top box | |
| CN103546041A (en) | Tri-level flyback converter main circuit topology | |
| CN210839041U (en) | Charging device and driving power generation circuit | |
| CN210405094U (en) | Bidirectional DC conversion circuit, bidirectional DC converter and electrical equipment | |
| CN211018672U (en) | Active diode circuit and alternating current-direct current power supply conversion circuit | |
| CN208063051U (en) | A kind of Switching Power Supply of photovoltaic DC-to-AC converter | |
| CN112636595A (en) | Auxiliary power supply circuit, power supply device and power supply circuit | |
| CN215186465U (en) | Flying capacitor three-level boost circuit | |
| CN213547169U (en) | Centralized charging device for multiple groups of batteries | |
| CN211744354U (en) | Feedback load circuit and power supply aging test equipment | |
| CN110601323B (en) | Charging device and driving power supply generating circuit | |
| CN113595412B (en) | LLC circuit and switching power supply |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |