CN114301436A - IGBT driving and protecting circuit - Google Patents
IGBT driving and protecting circuit Download PDFInfo
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- CN114301436A CN114301436A CN202111665763.4A CN202111665763A CN114301436A CN 114301436 A CN114301436 A CN 114301436A CN 202111665763 A CN202111665763 A CN 202111665763A CN 114301436 A CN114301436 A CN 114301436A
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Abstract
The invention discloses an IGBT driving and protecting circuit, which comprises a fault processing module, a micro control module and a driving module, wherein a driving signal is sent to the input end of the micro control module, and the output end of the micro control module is connected with the driving module and is used for controlling the driving module to output the driving signal so as to drive the IGBT to work; the fault processing module is used for collecting the grid voltage and the emitter collector voltage of the IGBT, and the output end of the fault processing module is connected with the micro control module; the micro control module controls the work of the control drive module at the rear end according to the transmitted drive signal, and controls the drive module to output a low level signal to the grid of the IGBT to close the IGBT output when a fault occurs. The invention has the advantages that: the selection of the device is optimized, a special isolation driving chip is not needed, the IGBT can be driven to normally work by using a micro-processing chip or a logic processing chip, the cost is reduced, and the applicability is increased. The drive has a complete protection circuit, the short circuit of the insulated gate device is detected, the microprocessing chip controls the grid to output low level, and the IGBT is turned off, so that the IGBT is protected.
Description
Technical Field
The invention relates to the field of drive control of power electronic devices, in particular to an IGBT (insulated gate bipolar transistor) drive and protection circuit.
Background
With the continuous progress of science and technology, the power electronic technology is rapidly developed, the electronic technology is the science of designing and manufacturing a circuit with a certain specific function by using electronic components according to the principle of electronics so as to solve the practical problem, and the electronic technology is the technology for processing electronic signals and realizing electric energy conversion. The application of power electronics is not separated in industrial control and energy industry, wherein an IGBT (insulated gate bipolar transistor) is a mainstream power semiconductor device at present. The drive circuit as drive power electron IGBT is also more mature, in the current scheme, most use the scheme that integrates, for example integrated form driver chip, this scheme makes IGBT control become simple, only need to match certain resistance-capacitance circuit and just can accomplish the arrangement of drive technique, but this scheme is because of having chooseed for use dedicated isolation driver chip, has caused the promotion by a wide margin of circuit cost, and the price receives market influence great, be unfavorable for the stable iteration of product, and also be not suitable for some to the more extensive region of the strict and commonality requirement of cost. Therefore, the invention provides a drive control scheme, the traditional drive chip is isolated, and a corresponding drive and protection scheme is provided, so that the circuit cost is reduced, and the applicability of the circuit is enhanced.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides an IGBT driving and protecting circuit which is used for realizing the driving control of an IGBT through a simple circuit and can protect the IGBT in case of failure.
The utility model provides a IGBT drive and protection circuit which characterized in that: the IGBT driving circuit comprises a fault processing module, a micro control module and a driving module, wherein a driving signal is sent to the input end of the micro control module, and the output end of the micro control module is connected with the driving module and is used for controlling the driving module to output the driving signal so as to drive the IGBT to work; the fault processing module is used for collecting the grid voltage and the emitter collector voltage of the IGBT, and the output end of the fault processing module is connected with the micro control module; the micro control module controls the work of the control drive module at the rear end according to the transmitted drive signal, and controls the drive module to output a low level signal to the grid of the IGBT to close the IGBT output when a fault occurs.
The IGBT driving and protecting circuit is characterized in that: the driving module comprises switching tubes Q1 and Q2 and resistors Ron and Roff, and the grid electrode of the switching tube Q1 and the grid electrode of the switching tube Q2 are connected to the output end of the micro-control module; the source of the Q1 is connected with a power supply VCC, and the drain of the Q1 is connected with the gate of the IGBT through a resistor Ron; the source of the Q2 is connected with a power supply VSS, and the drain of the Q2 is connected with the gate of the IGBT through a resistor Roff; the Q1 and the Q2 are NPN type switching tubes and PNP type switching tubes respectively.
The fault processing module comprises comparators COMP1 and COMP2, wherein the inverting input ends of the comparators COMP1 are connected to the grid electrode of the IGBT, the inverting end of the COMP2 is connected to the collector electrode of the power electronic IGBT through R1 and D1, and the inverting end of the COMP2 is connected with a capacitor C1 and a resistor R2 in parallel to the emitter; a non-inverting input end of the comparator COMP1 inputs a first comparison reference Vref 1; a non-inverting input end of the comparator COMP2 inputs a second comparison reference Vref 2; the output ends of the comparators COMP1 and COMP2 are connected to the input end of the micro control module.
The first comparison reference is larger than the maximum opening voltage of the grid electrode when the insulated gate device works normally, and the voltage determined by the time that the IGBT can bear short-circuit current is not larger than the voltage generated by charging time of two ends of a bus pair capacitor C1 during short circuit.
The charge-discharge formula of the C1 capacitor is as follows:
Vt＝VO+(V1-V0)*[1-exp(-t/RC)]
t＝RC*Ln[(V1-V0)/(V1-Vt)]
vt: the voltage value of the capacitor at the moment t;
v0, which is the initial voltage value on the capacitor;
v1: the voltage value that the capacitor can be charged or discharged finally;
t: charging or discharging time;
note: the exp () above represents an exponential function with e as the base; ln () is a base e logarithmic function.
The micro control module comprises a AND gate U1 and a U2, and a driving signal input end is connected to a first input end of an AND gate U1; a second input of the and gate U1 is connected to an output of the and gate U2. A first input terminal of the and gate U2 is connected to an output terminal of the comparator COMP1, and a second input terminal of the and gate U2 is connected to an output terminal of the comparator COMP 2.
The driving signal is sent by the signal generating equipment and is connected with the micro control module after passing through the isolation module.
The invention has the advantages that: the selection of the device is optimized, a special isolation driving chip is not needed, the IGBT can be driven to normally work by using a micro-processing chip or a logic processing chip, the cost is reduced, and the applicability is increased. The drive has a complete protection circuit, the short circuit of the insulated gate device is detected, the microprocessing chip controls the grid to output low level, and the IGBT is turned off, so that the IGBT is protected.
Drawings
The contents of the expressions in the various figures of the present specification and the labels in the figures are briefly described as follows:
FIG. 1 is a schematic diagram of a driving protection circuit according to the present invention;
fig. 2 is a circuit diagram of the driving protection circuit of the present invention.
Detailed Description
The following description of preferred embodiments of the invention will be made in further detail with reference to the accompanying drawings.
The IGBT driving protection circuit is low in cost and wide in application range, and accordingly the IGBT driving protection circuit can drive the IGBT without a special chip and can achieve the protection function. Compared with the conventional mode of driving power electronics by using a driving chip, the invention particularly provides a mode of using micro-control driving, and has a complete fault protection circuit, thereby effectively reducing the design cost and improving the driving stability. The invention uses a driving and protecting circuit, a microcontroller is used for receiving a driving signal and controlling the driving signal to drive an insulated gate device to work, and a detection module is used for acquiring the voltage of a grid electrode and a collector electrode emitter of the insulated gate device and outputting a state detection signal to the control module according to the voltage of the insulated gate device.
As shown in fig. 1, the present invention discloses a power electronic driving and protection circuit, which includes a magnetic isolation module, a transformer module, a microcontroller module, a driving module, a fault detection module and a power electronic module. The power electronic module may be a mainstream power semiconductor device, such as an Insulated Gate Bipolar Transistor (IGBT), which is now used in bulk in the motor controller. The isolation module is a magnetic induction module which is commonly used and can also be a photoelectric isolation module. The transformer module provides the isolated power supply voltage to the micro control module and the driving module at the rear end for realizing power supply. The other end of the driving module is connected with the control module, one end of the fault processing module is respectively connected with the grid electrode and the collector electrode of the insulated gate device, and the other end of the fault processing module is connected with the control module. The state detection module is used for obtaining the voltages of a grid electrode and a collector electrode of the insulated gate device and outputting a state detection signal to the control module according to the voltages, and the control module is used for judging whether the insulated gate device is short-circuited or not according to the state detection signal and controlling the driving module to output a low level to the grid electrode of the insulated gate device when the insulated gate device is short-circuited, so that the IGBT is turned off and the power device is protected. The invention provides a protection method of a drive protection circuit, which effectively avoids the current after the short circuit of an insulated gate device from burning out the drive circuit, thereby reducing the loss.
The circuit connection relation of the application is specifically shown in fig. 1 and 2, the IGBT driving and protecting circuit comprises a fault processing module, a micro control module and a driving module, wherein a driving signal is sent to the input end of the micro control module, and the output end of the micro control module is connected with the driving module and is used for controlling the driving module to output the driving signal so as to drive the IGBT to work; the fault processing module is used for collecting the grid voltage and the emitter collector voltage of the IGBT, and the output end of the fault processing module is connected with the micro control module; the micro control module controls the work of the control drive module at the rear end according to the transmitted drive signal, and controls the drive module to output a low level signal to the grid of the IGBT to close the IGBT output when a fault occurs.
The driving module comprises switching tubes Q1 and Q2 and resistors Ron and Roff, and the grid electrode of the switching tube Q1 and the grid electrode of the switching tube Q2 are connected to the output end of the micro-control module; the source of the Q1 is connected with a power supply VCC, and the drain of the Q1 is connected with the gate of the IGBT through a resistor Ron; the source of the Q2 is connected with a power supply VSS, and the drain of the Q2 is connected with the gate of the IGBT through a resistor Roff; the Q1 and the Q2 are NPN type switching tubes and PNP type switching tubes respectively.
The IGBT driving and protecting circuit is characterized in that: the fault processing module comprises comparators COMP1 and COMP2, wherein the inverting input ends of the comparators COMP1 are connected to the grid electrode of the IGBT, the inverting end of the COMP2 is connected to the collector electrode of the power electronic IGBT through R1 and D1, and the inverting end of the COMP2 is connected with a capacitor C1 and a resistor R2 in parallel to the emitter; a non-inverting input end of the comparator COMP1 inputs a first comparison reference Vref 1; a non-inverting input end of the comparator COMP2 inputs a second comparison reference Vref 2; the output ends of the comparators COMP1 and COMP2 are connected to the input end of the micro control module.
The IGBT driving and protecting circuit is characterized in that: the first comparison reference is larger than the maximum opening voltage of the grid electrode when the insulated gate device works normally, and the voltage determined by the time that the IGBT can bear short-circuit current is not larger than the voltage generated by charging time of two ends of a bus pair capacitor C1 during short circuit.
The charge-discharge formula of the C1 capacitor is as follows:
Vt＝VO+(V1-V0)*[1-exp(-t/RC)]
t＝RC*Ln[(V1-V0)/(V1-Vt)]
vt: the voltage value of the capacitor at the moment t;
v0, which is the initial voltage value on the capacitor;
v1: the voltage value that the capacitor can be charged or discharged finally;
t: charging or discharging time;
note: the exp () above represents an exponential function with e as the base; ln () is a base e logarithmic function.
The micro control module comprises a AND gate U1 and a U2, and a driving signal input end is connected to a first input end of an AND gate U1; a second input of the and gate U1 is connected to an output of the and gate U2. A first input terminal of the and gate U2 is connected to an output terminal of the comparator COMP1, and a second input terminal of the and gate U2 is connected to an output terminal of the comparator COMP 2.
The circuit principle of the application is as follows: and the driving module outputs a normal driving voltage signal to the grid electrode of the insulated gate device under the control of the driving signal processed by the control module, so that the insulated gate device continuously and normally works. When a fault occurs, the driving module outputs a low level to the insulated gate device under the control of the driving signal processed by the control module, so that a grid short circuit loop of the insulated gate device is cut off. Therefore, the driving module can be effectively prevented from being burnt by short-circuit current, and the loss is reduced.
The control module comprises two AND gates AND, a first input terminal of the AND gate U1 is connected to the isolated driving signal AND is configured to receive the driving signal from the signal generating device, AND a second input terminal of the AND gate U1 is electrically connected to an output terminal of the AND gate U2. A first input terminal of the and-gate U2 is connected to the output terminal of said comparator COMP1, and a second input terminal is connected to the output terminal of the comparator COMP 2.
The driving module comprises switching tubes Q1 and Q2 and resistors Ron and Roff, and the grid electrode of the switching tube Q1 and the grid electrode of the Q2 are connected to the output end of the micro-control module; the source of Q1 is connected with a power supply VCC, and the drain of Q1 is connected with the gate of the IGBT through a resistor Ron; the source of Q2 is connected with power supply VSS, and the drain of Q2 is connected with the grid of IGBT through resistor Roff; the Q1 and the Q2 are NPN type switching tubes and PNP type switching tubes respectively.
The status detection module comprises two comparators COMPl, COMP 2. A first input end of the comparator COMPl is connected to the gate of the insulated gate device. The COMP2 reverse terminal is connected to the collector of the power electronic IGBT through R1 and D1, and the COMP2 reverse terminal is connected to the emitter in parallel with a capacitor C1 and a resistor R2.
The power supply VSS is electrically connected to a second input terminal of the comparator COMP1 to provide a first comparison reference Vref 1. The power supply VSS is electrically connected to a second input terminal of the comparator COMP2 to provide a second comparison reference Vref2, an output terminal of the comparator COMP1 is electrically connected to a first input terminal of the and gate U2, and an output terminal of the comparator COMP2 is electrically connected to a second input terminal of the and gate U2. The first comparison reference is larger than the maximum opening voltage of the grid electrode when the insulated gate device works normally, and the voltage determined by the time that the IGBT can bear short-circuit current is not larger than the voltage generated by charging time of two ends of a bus pair capacitor C1 during short circuit.
According to the working principle of the fault processing module, the comparator COMP1 is used for detecting the normal driving voltage of the insulated gate, when the driving voltage of the gate is normal, the voltage of the reverse end of the comparator COMP1 is smaller than the reference voltage Vref1 of the same-direction end, at the moment, the output end of the comparator COMP1 outputs a high level, when a fault occurs, when the driving voltage of the gate is not normal, the voltage of the reverse end of the comparator COMP1 is larger than the reference voltage Vref1 of the same-direction end, and at the moment, the output end of the comparator COMP1 outputs a bottom level. The comparator COMP2 is used for detecting the collector emitter voltage of the insulated gate, that is, the voltage at the two ends of the capacitor C1, and an RC network is used for short-circuit protection detection, and the protection method uses the IGBT desaturation effect to detect the VCE (collector emitter) saturation conduction voltage drop when the IGBT is turned on, and compares the VCE with a reference value Vref2 set inside the chip to determine whether a short circuit occurs. The driver employs an RC network to detect the VCE. When the IGBT is turned off, C1 will internally discharge through resistor R2 and pull VCE down to VSS at which VCE < Vref2, the driver will not falsely fault. When the IGBT is normally turned on, the voltage VCE of the IGBT collector with respect to the emitter E gradually decreases to the VCE saturation turn-on voltage drop of the IGBT itself, and is charged through the resistor R1, and until VCE is equal to VCESAT but still less than Vref2, the driver does not falsely report a fault. When the IGBT is short-circuited, the voltage VCE of the IGBT collector C relative to the voltage VCE of the IGBT collector E bears the bus voltage HV +, the VCE is charged through the resistor R1, the VCE is increased all the time, and when the set reference voltage Vref2 is exceeded, the output end of the comparator COMP2 outputs a low level which is transmitted to the AND gate U2 so as to control the driving module to actively turn off the short-circuited IGBT module.
When the insulated gate device is in normal operation, the inverting input terminal of the comparator COMP1 obtains the gate voltage of the insulated gate device to compare with the first comparison reference Vref1, the inverting input terminal of the comparator COMP2 obtains the voltage across the C1, and compares with the second comparison reference Vref2, when the insulated gate device is in normal switching state, the comparator COMP1 and the comparator COMP2 both output high level signals, the output terminal of the and gate U2 outputs high level signals, if the driving signal is at low level, the high level signals and the low level driving signal are input to the and gate U1 together, and a low level signal is output to the driving module, at this time, the electronic switch Q1 is turned off, the electronic switch Q2 is turned on, so that the driving module outputs a low level state to maintain the insulated gate device in off state operation, if the driving signal is at a high level, the high-level signal and the high-level driving signal are input to the and gate U1 together, and a high-level signal is output to the driving module, and at this time, the electronic switch Q1 is turned on, and the electronic switch Q2 is turned off, so that the driving module outputs a high-level state to maintain the insulated gate device in an on state to work, and at this time, it represents that the insulated gate device has no abnormal short circuit state and is in a normal switching state of the driven signal controller.
When the insulated gate device is in short-circuit operation, the inverting input terminal of the comparator COMP1 obtains the gate voltage of the insulated gate device to compare with the first comparison reference Vref1, the inverting input terminal of the comparator COMP2 obtains the voltage across the C1, and compares with the second comparison reference Vref2, when the insulated gate device is in abnormal switching state, the comparator COMP1 and the comparator COMP2 both output low level signals, or when only one of the output terminals of the comparators COMP1 and COMP2 is in low level, the output terminal of the and gate U2 outputs low level signals, if the driving signal is in low level, the low level signals and the low level driving signal are input to the and gate U1 together, and output the low level signals to the driving module, and when the electronic switch Q1 is turned off, the electronic switch Q2 is turned on, and thus, the driving module will output a low level state, the insulated gate device is maintained to be in a closed state to work, if the driving signal is at a high level at the moment, the low level signal and the driving signal at the high level are input into the and gate U1 together, and a low level signal is output to the driving module, at the moment, the electronic switch Q1 is turned off, and the electronic switch Q2 is turned on, so that the driving module outputs a low level state to close the insulated gate device to work in a closed state, at the moment, the insulated gate device is in a short-circuit state, the insulated gate device is driven and controlled to be turned off, and the short-circuited insulated gate device is turned off. Thereby protecting the device from damage.
It is clear that the specific implementation of the invention is not restricted to the above-described embodiments, but that various insubstantial modifications of the inventive process concept and technical solutions are within the scope of protection of the invention.
Claims (6)
1. The utility model provides a IGBT drive and protection circuit which characterized in that: the IGBT driving circuit comprises a fault processing module, a micro control module and a driving module, wherein a driving signal is sent to the input end of the micro control module, and the output end of the micro control module is connected with the driving module and is used for controlling the driving module to output the driving signal so as to drive the IGBT to work; the fault processing module is used for collecting the grid voltage and the emitter collector voltage of the IGBT, and the output end of the fault processing module is connected with the micro control module; the micro control module controls the work of the control drive module at the rear end according to the transmitted drive signal, and controls the drive module to output a low level signal to the grid of the IGBT to close the IGBT output when a fault occurs.
2. The IGBT driving and protection circuit of claim 1, wherein: the driving module comprises switching tubes Q1 and Q2 and resistors Ron and Roff, and the grid electrode of the switching tube Q1 and the grid electrode of the switching tube Q2 are connected to the output end of the micro-control module; the source of the Q1 is connected with a power supply VCC, and the drain of the Q1 is connected with the gate of the IGBT through a resistor Ron; the source of the Q2 is connected with a power supply VSS, and the drain of the Q2 is connected with the gate of the IGBT through a resistor Roff; the Q1 and the Q2 are NPN type switching tubes and PNP type switching tubes respectively.
3. The IGBT driving and protection circuit according to claim 1 or 2, wherein: the fault processing module comprises comparators COMP1 and COMP2, wherein the inverting input ends of the comparators COMP1 are connected to the grid electrode of the IGBT, the inverting end of the COMP2 is connected to the collector electrode of the power electronic IGBT through R1 and D1, and the inverting end of the COMP2 is connected with a capacitor C1 and a resistor R2 in parallel to the emitter; a non-inverting input end of the comparator COMP1 inputs a first comparison reference Vref 1; a non-inverting input end of the comparator COMP2 inputs a second comparison reference Vref 2; the output ends of the comparators COMP1 and COMP2 are connected to the input end of the micro control module.
4. The IGBT driving and protection circuit of claim 3, wherein: the first comparison reference is larger than the maximum opening voltage of the grid electrode when the insulated gate device works normally, and the voltage determined by the time that the IGBT can bear short-circuit current is not larger than the voltage generated by charging time of two ends of a bus pair capacitor C1 during short circuit.
5. The IGBT drive protection circuit of claim 3, wherein: the micro control module comprises a AND gate U1 and a U2, and a driving signal input end is connected to a first input end of an AND gate U1; a second input of the and gate U1 is connected to an output of the and gate U2. A first input terminal of the and gate U2 is connected to an output terminal of the comparator COMP1, and a second input terminal of the and gate U2 is connected to an output terminal of the comparator COMP 2.
6. The IGBT driving and protection circuit according to claim 1 or 2, wherein: the driving signal is sent by the signal generating equipment and is connected with the micro control module after passing through the isolation module.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111665763.4A CN114301436A (en) | 2021-12-31 | 2021-12-31 | IGBT driving and protecting circuit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111665763.4A CN114301436A (en) | 2021-12-31 | 2021-12-31 | IGBT driving and protecting circuit |
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| CN114301436A true CN114301436A (en) | 2022-04-08 |
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| CN202111665763.4A Pending CN114301436A (en) | 2021-12-31 | 2021-12-31 | IGBT driving and protecting circuit |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116759995A (en) * | 2023-08-23 | 2023-09-15 | 深圳深蕾科技股份有限公司 | Driving fault protection circuit for single power module driving chip |
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2021
- 2021-12-31 CN CN202111665763.4A patent/CN114301436A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116759995A (en) * | 2023-08-23 | 2023-09-15 | 深圳深蕾科技股份有限公司 | Driving fault protection circuit for single power module driving chip |
| CN116759995B (en) * | 2023-08-23 | 2024-02-13 | 深圳深蕾科技股份有限公司 | Driving fault protection circuit for single power module driving chip |
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