IGBT protection circuit

Abstract

The utility model discloses an IGBT (Insulated Gate Bipolar Transistor) protection circuit, which comprises a driving module, the input control end of the driving module is connected with the cathode of a Zener diode D0, and the cathode of the Zener diode D0 is also connected to the emitter E of an insulated gate bipolar transistor Q0. The grid electrode G of the insulated gate bipolar transistor Q0 is connected to the driving output end of the driving module through a resistor R6, and the collector electrode C of the insulated gate bipolar transistor Q0 is connected with the overcurrent detection output end of the driving module through a fast recovery diode FR107. According to the technical scheme, transient voltage spikes can be effectively restrained, the IGBT is protected against overvoltage damage, the anti-interference capacity of the circuit is enhanced, a fast recovery diode FR107 is further arranged at the overcurrent detection output end of the driving module, the switching speed can be increased, the overvoltage phenomenon during switching-off is reduced, the service life of the IGBT and the driving module is prolonged, and the service life of the IGBT and the driving module is prolonged. And the working reliability of the whole circuit is improved.

Description

Technical Field

[0001] The utility model belongs to the field of IGBT charging and discharging protection, and specifically relates to an IGBT protection circuit. Background Art

[0002] In modern power electronics technology, insulated gate bipolar transistors (IGBTs) are an important power semiconductor device that is widely used in inverters, uninterruptible power supplies (UPS), electric vehicle drive systems, and other fields. They are favored because they have both the high input impedance of MOSFETs and the low on-state voltage drop characteristics of bipolar transistors. However, IGBTs are susceptible to various external interferences and internal faults such as overvoltage and overcurrent in high-voltage and high-current working environments. These factors will not only reduce the performance of IGBTs, but also cause device damage in severe cases.

[0003] Traditional IGBT protection strategies mostly rely on simple voltage or current detection loops, such as an IGBT drive circuit based on the EXB841 chip with a publication number of CN201629666U, including a chip of model NE555P and a chip of model 6N137, the third pin of the NE555P chip is connected to one of the inputs of the AND gate, the output of the AND gate is connected to the fifteenth pin of the EX841 chip, the second pin of the NE555P chip is connected to the collector of the transistor through the fifth resistor, the base of the transistor is connected through the sixth pin of the 6N137 chip, the collector of the transistor is connected to one of the inputs of the OR gate, and the output of the OR gate is connected to the other input of the AND gate. In the process of soft shutdown when the EXB841 detects overcurrent, in order to prevent the external input signal from being removed, the IGBT is directly hard-shut down, but these methods often have slow response speeds, limited protection accuracy, and poor protection effects for transient overvoltages and complex working conditions. Especially in application scenarios with high dynamic response requirements, the lack of protection measures directly limits the reliability and efficiency of the entire system. Utility Model Content

[0004] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide an IGBT protection circuit. The utility model is implemented through the following technical solutions:

[0005] An IGBT protection circuit comprises a driving module, wherein an input control terminal of the driving module is connected to a cathode of a voltage stabilizing diode D0, the cathode of the voltage stabilizing diode D0 is also connected to an emitter E of an insulated gate bipolar transistor Q0, a gate G of the insulated gate bipolar transistor Q0 is connected to a driving output terminal of the driving module via a resistor R6, and a collector C of the insulated gate bipolar transistor Q0 is connected to an overcurrent detection output terminal of the driving module via a fast recovery diode FR107.

[0006] Preferably, an isolation module is also included, which includes a trigger RS, an AND gate AND and a fast optocoupler, the Q pin of the trigger RS ​​is connected to the data input terminal 1 of the AND gate AND, the S pin of the trigger RS ​​and the data input terminal 2 of the AND gate AND constitute the input terminal signal of the circuit, the data output terminal of the AND gate AND is connected to the driving signal input terminal of the driving module through a resistor R5, the collector of the fast optocoupler is connected to the positive electrode 5V through a pull-up resistor R2, the anode of the fast optocoupler is connected to the positive electrode 20V through a pull-up resistor R4, and the cathode of the fast optocoupler is connected to the overcurrent detection output terminal of the driving module.

[0007] Preferably, the R pin of the trigger RS ​​of the isolation module is also connected to one end of the button SW4, and the other end of the button SW4 is connected to the positive electrode 5V through the pull-up resistor R2.

[0008] Preferably, a voltage stabilizing diode C4 and a capacitor C5 are connected in parallel to the input control terminal of the driving module.

[0009] Preferably, the input port of the IGBT protection circuit is provided with a Hall voltage sensor and a Hall current sensor.

[0010] Compared with the prior art, the beneficial effects of the utility model are:

[0011] 1. By connecting the voltage stabilizing diode D0 to the input control terminal of the driver module, the transient voltage spike can be effectively suppressed, the IGBT can be protected from overvoltage damage, the driving signal can be stabilized, and the anti-interference ability of the circuit can be enhanced. Further, a fast recovery diode FR107 is set at the overcurrent detection output end of the driver module to increase the switching speed and reduce the overvoltage phenomenon during shutdown, thereby extending the service life of the IGBT and the driver module and improving the working reliability of the entire circuit.

[0012] 2. The electrical isolation performance of the circuit is enhanced by introducing the isolation module trigger RS ​​and fast optocoupler, which effectively prevents the direct impact of high voltage or high current on the control circuit, improves the safety of the system, and realizes low-latency action through the coordination of various components to respond to abnormal conditions in the circuit in a timely manner.

[0013] 3. By adding a reset button SW4 at the R end of the trigger RS, when the fault is eliminated, the reset button can be pressed to release the blockade of the gate signal, realizing a manual intervention or control mechanism, allowing the user to manually trigger the protection action or perform system testing as needed, improving the system's operational flexibility and maintenance convenience, and enhancing the user experience.

[0014] 4. By integrating the Hall voltage sensor and the Hall current sensor at the input end of the IGBT protection circuit, the voltage and current changes in the circuit can be monitored in real time and accurately, and overvoltage or overcurrent conditions can be detected in time, thereby quickly starting the protection mechanism to prevent the IGBT and other components from being damaged due to abnormal working conditions. The response speed and accuracy of the circuit protection are significantly improved, and the safe and stable operation of power electronic equipment is ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the driving and protection circuit of the utility model. DETAILED DESCRIPTION

[0016] The utility model is further described below in conjunction with the accompanying drawings.

[0017] Embodiment 1

[0018] like Figure 1 As shown, an embodiment provides an IGBT protection circuit, including a driving module, an input control end of the driving module is connected to the cathode of a voltage regulator diode D0, the cathode of the voltage regulator diode D0 is also connected to the emitter E of an insulated gate bipolar transistor Q0, a gate G of the insulated gate bipolar transistor Q0 is connected to the driving output end of the driving module through a resistor R6, and a collector C of the insulated gate bipolar transistor Q0 is connected to the overcurrent detection output end of the driving module through a fast recovery diode FR107.

[0019] Preferably, a voltage stabilizing diode C4 and a capacitor C5 are connected in parallel to the input control terminal of the driving module to realize a voltage stabilizing function and improve the voltage stabilizing capability of the circuit.

[0020] Specifically, the driving module adopts EXB841, the pin 1 of the driving module EXB481 is connected in parallel with a voltage zener diode C4 and a capacitor C5, the pin 9 of the driving module EXB481 is grounded, the pin 1 of the driving module EXB481 is connected with the cathode of the voltage zener diode D0, the cathode of the voltage zener diode D0 is also connected to the wire of the emitter E of the insulated gate bipolar transistor Q0, the insulated gate bipolar transistor Q0 is connected to the pin 3 of the driving module EXB841 through a resistor R6, and the collector C of the insulated gate bipolar transistor Q0 is connected to the pin 6 of the driving module EXB841 through a fast recovery diode FR107. After the collector current monitoring is completed, the gate voltage value can be quickly reduced within 10us, so that the IGBT enters soft shutdown, the reverse recovery time of FR107 is about 150ns, and the forward conduction voltage drop is 3V. The use of the reverse recovery diode FR107 ensures the reaction speed of the overcurrent protection.

[0021] By connecting the Zener diode C4 and capacitor C5 in parallel to the pin 9 of the driver module EXB841 to achieve the voltage stabilization function, and connecting the Zener diode D0 to the pin 1, the transient voltage spike can be effectively suppressed to protect the EXB841 from overvoltage damage, while stabilizing the drive signal and enhancing the circuit's anti-interference ability. The use of the fast recovery diode FR107 increases the switching speed and reduces the overvoltage phenomenon during shutdown, thereby extending the service life of the IGBT and the driver module and improving the working reliability of the entire circuit.

[0022] Embodiment 2

[0023] In this embodiment, based on the first embodiment, the IGBT protection circuit further includes an isolation module, which includes a trigger RS, an AND gate AND and a fast optocoupler, the Q pin of the trigger RS ​​is connected to the data input terminal 1 of the AND gate AND, the S pin of the trigger RS ​​and the data input terminal 2 of the AND gate AND constitute the input terminal signal of the circuit, the data output terminal of the AND gate AND is connected to the driving signal input terminal of the driving module through a resistor R5, the collector of the fast optocoupler is connected to the positive electrode 5V through a pull-up resistor R2, the anode of the fast optocoupler is connected to the positive electrode 20V through a pull-up resistor R4, and the cathode of the fast optocoupler is connected to the overcurrent detection output terminal of the driving module.

[0024] Specifically, the isolation module trigger RS ​​is CD4043, the AND gate AND is 4081, the fast optocoupler is 4N35, the R pin of the trigger RS ​​is grounded through a resistor R1, the Q pin of the trigger RS ​​is connected to pin 1 of the AND gate AND, the S pin of the trigger RS ​​and pin 2 of the AND gate AND constitute the input signal of the circuit, pin 2 of the AND gate AND is grounded, pin 3 of the AND gate AND is connected to pin 15 of the EXB841 through a resistor R5, pin 5 of the fast optocoupler 4N35 is connected to the positive pole 5V through a pull-up resistor R2, pin 4 of the fast optocoupler 4N35 is grounded, pin 1 of the fast optocoupler 4N35 is connected to the positive pole 20V through a pull-up resistor R4, and pin 2 of the fast optocoupler 4N35 is connected to pin 5 of the EXB841 module.

[0025] The delay signal of the fast optocoupler 4N35 is about 0-10μs, the delay signal of the AND gate AND is about 10-100ns, and the delay signal of the trigger RS ​​is about 100-900ns. The electrical isolation performance of the circuit is enhanced by introducing the isolation module trigger RS ​​and the fast optocoupler 4N35, effectively preventing the direct impact of high voltage or high current on the control circuit, improving the safety of the system, and at the same time, through the cooperation of various components to achieve low-delay action, timely respond to abnormal conditions in the circuit.

[0026] Embodiment 3

[0027] In this embodiment, based on the second embodiment, the R pin of the isolation module trigger RS ​​is further connected to one end of the button SW4, and the other end of the button SW4 is connected to the positive electrode 5V through the pull-up resistor R2.

[0028] By adding a reset button SW4 to the R end of the trigger RS, when the fault is eliminated, the reset button can be pressed to release the blockade of the gate signal, realizing a manual intervention or control mechanism, allowing the user to manually trigger the protection action or perform system testing as needed, improving the system's operational flexibility and maintenance convenience, and enhancing the user experience.

[0029] Preferably, the input port of the IGBT protection circuit is also provided with a Hall voltage sensor and a Hall current sensor. By integrating the Hall voltage sensor and the Hall current sensor at the input end of the IGBT protection circuit, the voltage and current changes in the circuit can be monitored in real time and accurately, and overvoltage or overcurrent conditions can be detected in time, so as to quickly start the protection mechanism to prevent the IGBT and other components from being damaged due to abnormal working conditions, significantly improve the response speed and accuracy of the circuit protection, and ensure the safe and stable operation of power electronic equipment.

[0030] Furthermore, when the IGBT protection circuit is applied to the battery charging and discharging circuit, it mainly includes the isolation drive of the switch tube, overcurrent protection and reset, terminal voltage detection, and loop current detection. The isolation drive circuit composed of EXB841, after an overcurrent occurs, the driver sends an overcurrent signal, and the gate locks the PWM signal input. After the button SW4 is pressed, the trigger RS ​​is triggered to resume normal operation.

Claims

1. An IGBT protection circuit, comprising a drive module, characterized in that: The input control end of the driving module is connected to the cathode of the voltage stabilizing diode D0, and the cathode of the voltage stabilizing diode D0 is also connected to the emitter E of the insulated gate bipolar transistor Q0. The gate G of the insulated gate bipolar transistor Q0 is connected to the driving output end of the driving module through a resistor R6. The collector C of the insulated gate bipolar transistor Q0 is connected to the overcurrent detection output end of the driving module through a fast recovery diode FR107.

2. The IGBT protection circuit according to claim 1, characterized in that: It also includes an isolation module, which includes a trigger RS, an AND gate AND and a fast optocoupler, the Q pin of the trigger RS ​​is connected to the data input terminal 1 of the AND gate AND, the S pin of the trigger RS ​​and the data input terminal 2 of the AND gate AND constitute the input terminal signal of the circuit, the data output terminal of the AND gate AND is connected to the driving signal input terminal of the driving module through a resistor R5, the collector of the fast optocoupler is connected to the positive electrode 5V through a pull-up resistor R2, the anode of the fast optocoupler is connected to the positive electrode 20V through a pull-up resistor R4, and the cathode of the fast optocoupler is connected to the overcurrent detection output terminal of the driving module.

3. The IGBT protection circuit according to claim 2, characterized in that: The R pin of the trigger RS ​​of the isolation module is also connected to one end of the button SW4, and the other end of the button SW4 is connected to the positive electrode 5V through the pull-up resistor R2.

4. The IGBT protection circuit according to claim 1, characterized in that: The input control terminal of the driving module is connected in parallel with a voltage stabilizing diode C4 and a capacitor C5.

5. The IGBT protection circuit according to claim 1, characterized in that: The input port of the IGBT protection circuit is provided with a Hall voltage sensor and a Hall current sensor.

Images