IGBT drive protection circuit

Abstract

This utility model discloses an IGBT drive protection circuit, including: a signal amplification module, an IGBT, a freewheeling diode, and a discharge module; a pulse control voltage is amplified by the signal amplification module and connected to the gate of the IGBT; the emitter of the IGBT is connected to ground potential, and the collector of the IGBT is connected to the DC bus via the freewheeling diode; a load motor is connected between the collector of the IGBT and the DC bus; the discharge module includes a first capacitor, a fifth resistor, a sixth resistor, a seventh resistor, and a third transistor; the collector of the third transistor is connected to the collector of the IGBT via the fifth resistor; the emitter of the third transistor is connected to ground potential; the gate of the third transistor is connected to the collector of the IGBT via the seventh resistor and the first capacitor in series, and is also connected to ground potential via the sixth resistor. This utility model can realize IGBT overvoltage protection for high-voltage units, prevent IGBT damage, improve unit operation reliability, and enhance user satisfaction.

Description

Technical Field

[0001] This utility model relates to the field of air conditioning technology, specifically to an IGBT drive protection circuit. Background Technology

[0002] In the field of air conditioning technology, the stable operation of power electronic devices plays a crucial role in the performance and reliability of air conditioning systems. Among them, the insulated gate bipolar transistor (IGBT), as a key power device in air conditioning circuits, has always been a focus of industry attention due to its overvoltage suppression problem.

[0003] In conventional air conditioning operation, the power input is typically a single-phase AC power of 220V, which is rectified to obtain a DC bus voltage of approximately 310V. When using a three-phase power supply, the rectified DC bus voltage is around 540V. For these conventional power supply scenarios, the industry commonly uses capacitor absorption to suppress IGBT overvoltage. This involves using parallel capacitors to absorb the energy stored in the inductor during the commutation process. Specifically, during the commutation process in an air conditioning circuit, the inductor stores a certain amount of energy. If this energy is not released in time when the circuit state changes, it will generate an overvoltage across the IGBT, potentially damaging it and affecting the normal operation of the air conditioning system. The capacitor, with its energy storage characteristics, can effectively absorb this energy, thus suppressing the voltage across the IGBT within a safe range and ensuring its normal operation.

[0004] However, air conditioning products in North America require compatibility with three-phase power supply systems with a line voltage of 575V, resulting in a DC bus voltage as high as 820V after rectification. Under these high-voltage conditions, traditional capacitor absorption methods face two major technical challenges: firstly, conventional capacitors have limitations in their voltage withstand capability and capacitance, making it difficult to match the 820V DC bus voltage and posing a risk of breakdown; secondly, capacitor capacity design must balance energy storage requirements with size constraints, requiring an exponential increase in capacitance at high voltages to maintain the same energy absorption capacity, leading to a surge in device size and cost, severely contradicting the trend towards miniaturization and low cost. Therefore, the aforementioned method of absorbing inductor energy through capacitors is insufficient to effectively suppress IGBT overvoltage under high-voltage conditions. Thus, it is necessary to research new IGBT drive protection circuits for suppressing IGBT overvoltage under high-voltage power supplies. Utility Model Content

[0005] To address the shortcomings of existing technologies, this utility model provides an IGBT drive protection circuit, which aims to provide IGBT overvoltage protection for air conditioning units with high-voltage power supplies, especially high-voltage air conditioning units with a line voltage of 575V and a rectified DC voltage of 820V, thereby preventing IGBT damage under high-voltage conditions, improving the reliability of unit operation, and enhancing user satisfaction.

[0006] The present invention adopts the following technical solution.

[0007] In one embodiment, the present invention provides an IGBT protection circuit. The IGBT protection circuit includes: a pulse control voltage amplified by the signal amplification module and connected to the gate of the IGBT; the emitter of the IGBT connected to ground potential; the collector of the IGBT connected to a DC bus via a freewheeling diode; and a load motor connected between the collector of the IGBT and the DC bus. The discharge module includes a first capacitor, a fifth resistor, a sixth resistor, a seventh resistor, and a third transistor; the collector of the third transistor is connected to the collector of the IGBT via the fifth resistor; the emitter of the third transistor is connected to ground potential; the gate of the third transistor is connected to the collector of the IGBT via the seventh resistor and the first capacitor in series, and is connected to ground potential via the sixth resistor.

[0008] Preferably, when the IGBT is turned off and the voltage between the emitter and collector of the IGBT exceeds a preset threshold, the emitter and collector of the third transistor are turned on, and the fifth resistor and the third transistor form a discharge path to discharge the current and voltage of the collector of the IGBT to ground potential.

[0009] Preferably, when the IGBT is turned off, the energy stored in the first capacitor is released through a circuit formed by the sixth resistor, the third transistor, the fifth resistor, and the seventh resistor.

[0010] Preferably, the discharge module further includes a sixth diode; the positive terminal of the sixth diode is connected to ground potential, and the negative terminal is connected to the gate of the third transistor.

[0011] Preferably, the discharge module further includes a plurality of diodes connected in series between the base of the third transistor and the ground potential; the positive terminals of the plurality of diodes are close to the base of the third transistor, and the negative terminals of the plurality of diodes are close to the ground potential.

[0012] Preferably, the amplification module includes a current-limiting resistor, a push-pull amplifier, and a drive resistor; the pulse control voltage is connected to the gate of the IGBT via the series-connected current-limiting resistor, push-pull amplifier, and drive resistor.

[0013] Preferably, the IGBT protection circuit further includes a protection module; the protection module includes a second resistor and a dynamic feedback capacitor connected in series; The pulse control voltage is connected to the collector of the IGBT in sequence via the current-limiting resistor and the protection module.

[0014] Preferably, the IGBT protection circuit further includes a clamping module; the clamping module includes a third resistor, a second diode, a third diode, and a fourth resistor; The pulse control voltage is connected to the gate of the IGBT in sequence via a current-limiting resistor, a third resistor, and a fourth resistor; the collector of the IGBT is connected to the gate of the IGBT via a second diode, a third diode, and a fourth resistor; the anode of the second diode is connected to the anode of the third diode.

[0015] Preferably, a second capacitor is provided between the DC bus and the ground potential.

[0016] Preferably, the IGBT protection circuit further includes a clamping diode; the positive terminal of the clamping diode is connected to the emitter of the IGBT; and the negative terminal of the clamping diode is connected to the collector of the IGBT.

[0017] The beneficial effects of this invention are compared with those of the prior art: 1. By introducing a discharge module including a transistor, resistor, and capacitor between the collector and emitter, when the IGBT is turned off and the voltage between the emitter and collector of the IGBT exceeds a preset threshold, the emitter and collector of the transistor in the discharge module are turned on. The resistor and the transistor in the discharge module form a discharge path, discharging the current and voltage at the collector of the IGBT to ground potential. Simultaneously, the energy stored in the capacitor in the discharge module is released through the circuit formed by the resistor and the transistor.

[0018] 2. By introducing a protection circuit, a resistor is connected in series and parallel between the collector of the IGBT and the input terminal of the previous stage, so as to control the current flow and eliminate oscillation.

[0019] 3. By introducing a clamping circuit, a resistor is added to both the collector-gate of the IGBT and the front stage of the push-pull circuit to prevent the potential of the front stage of the push-pull circuit from rising and thus the gate voltage of the IGBT from rising.

[0020] This effectively enables ultra-high voltage protection for the IGBTs of 820V high-voltage air conditioning units. Attached Figure Description

[0021] Figure 1 This is the equivalent circuit diagram of an IGBT drive protection circuit used in a conventional voltage source; Figure 2 This is an equivalent circuit diagram of an IGBT drive protection circuit for a high-voltage power supply according to an embodiment of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. The embodiments described in this application are merely some embodiments of this utility model, not all embodiments. Based on the spirit of this utility model, other embodiments obtained by those skilled in the art without creative effort are all within the protection scope of this utility model.

[0023] Inadequacies of existing IGBT drive protection circuits for conventional voltage sources Figure 1 An equivalent circuit diagram of an IGBT drive protection circuit for a conventional voltage source is shown. Figure 1 A typical IGBT operating circuit usually includes: a current-limiting resistor R1, a push-pull amplifier, a drive resistor Rg, and the IGBT (corresponding to...). Figure 1 Z in the text refers to Z and FWD (Freewheeling Diode).

[0024] The pulse control voltage is connected to the gate of the IGBT via a series current-limiting resistor R1, a push-pull amplifier, and a drive resistor Rg; the emitter of the IGBT is connected to ground potential, and the collector of the IGBT is connected to the DC bus via the FWD. The load motor (e.g., an air conditioner motor) is connected between the collector of the IGBT and the DC bus.

[0025] Furthermore, the push-pull amplifier includes a first transistor Q1 and a second transistor Q2 connected in parallel with opposite polarities. Figure 1 In this configuration, the first transistor Q1 is a P-type transistor, and the second transistor Q2 is an N-type transistor. More specifically, the bases of the first transistor Q1 and the second transistor Q2 are connected together; the emitters of the first transistor Q1 and the second transistor Q2 are connected together; the collector of the first transistor Q1 is connected to a first reference voltage (e.g., +15V); and the collector of the second transistor Q2 is connected to a second reference voltage (e.g., -15V).

[0026] In addition, a clamping diode D1 is provided between the collector and emitter of the IGBT to clamp and control the collector-emitter voltage of the IGBT when it is broken down.

[0027] exist Figure 1In this case, considering that there are parasitic inductances in the DC bus, connecting wires, PCB traces and IGBT module pins, it can be equivalently considered that there is a stray inductance Lc connected in series at the collector of the IGBT, that is, the collector of the IGBT is connected to the load motor through the stray inductance Lc.

[0028] exist Figure 1 In this case, the load motor can be represented by the motor resistance Rm and motor inductance Lm connected in series.

[0029] In addition, Figure 1 In this study, considering the influence of the load motor, it is assumed that there is also a magnetizing inductance Le between the collector of the IGBT and the freewheeling diode FWD.

[0030] In order to absorb the energy stored in various inductive components (i.e., stray inductance Lc, motor inductance Lm, magnetizing inductance Le, etc.) in the circuit when the collector-emitter overvoltage of the IGBT is applied, and to prevent this energy from damaging the IGBT, a capacitor is also provided between the DC bus and the ground potential in the system.

[0031] If the aforementioned conventional IGBT drive protection circuit is applied to a high-voltage power supply, such as one with a rectified DC voltage of 820V, voltages higher than 820V may be generated on the DC bus due to grid fluctuations and abnormal shutdowns of the load motor. Most current devices have a peak voltage limit of 1200V; when using 575V high voltage, the rated voltage of 820V can be increased by 1.2 times to reach 984V. Especially when the abnormal shutdown of the load motor is combined with the parasitic parameters of the IGBT device itself, the voltage across the capacitor can exceed 1200V, directly damaging the device and affecting reliability.

[0032] The IGBT drive protection circuit of this invention overcomes the shortcomings of conventional IGBT drive protection circuits, thus making it suitable for high-voltage power supply applications, especially 820V high-voltage power supplies. The specific solution of this invention is described below.

[0033] It should be noted that in this utility model, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0034] In this utility model, if there are descriptions involving "first," "second," etc., such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0035] like Figure 2 As shown, in one embodiment, the IGBT drive protection circuit of this utility model includes: a signal amplification module, an IGBT (corresponding to...) Figure 2 The components include Z), freewheeling diode FWD, and bleeder module.

[0036] The pulse control voltage is amplified by the signal amplification module and then connected to the gate of the IGBT; the emitter of the IGBT is connected to ground potential, and the collector of the IGBT is connected to the DC bus (the rated voltage of the DC bus in this embodiment is 820V) via the freewheeling diode FWD; the load motor (e.g., an air conditioner motor) is connected between the collector of the IGBT and the DC bus. The discharge module includes a first capacitor C1, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and a third transistor Q3; the collector of the third transistor Q3 is connected to the collector of the IGBT via the fifth resistor R5; the emitter of the third transistor Q3 is connected to ground potential; the gate of the third transistor Q3 is connected to the collector of the IGBT via the seventh resistor R7 and the first capacitor C1 connected in series, and is connected to ground potential via the sixth resistor R6.

[0037] In this way, when the IGBT needs to be turned off due to an abnormality, causing the voltage between the emitter and collector of the IGBT to be too high and exceed the preset threshold, the third transistor Q3 is turned on. The fifth resistor R5 and the third transistor Q3 form a discharge path to discharge the large current and high voltage of the collector during the IGBT turn-off process to the reference ground potential.

[0038] Meanwhile, after the IGBT is turned off, the excess energy stored in the first capacitor C1 can be released through the circuit formed by the sixth resistor R6, the third transistor Q3, the fifth resistor R5, and the seventh resistor R7.

[0039] In a further preferred embodiment, the discharge module may further include a sixth diode D6. The positive terminal of the sixth diode D6 is connected to ground potential, and the negative terminal is connected to the gate of the third transistor Q3.

[0040] This protects the third transistor Q3 from overvoltage, thus preventing it from being damaged by overvoltage.

[0041] Preferably, the discharge module may further include a plurality of diodes connected in series between the base of the third transistor Q3 and the ground potential, for example... Figure 2 Diodes D7 to D11 are included. The positive terminals of the plurality of diodes are close to or connected to the gate of the third transistor Q3, and the negative terminals of the plurality of diodes are close to or connected to ground potential.

[0042] This allows for forward clamping of the third transistor Q3. It should be noted that the number of diodes can be selected based on different supply voltages, and each diode can also have a different voltage drop depending on the supply voltage.

[0043] In a further preferred embodiment, the signal amplification module in the IGBT drive protection circuit of this invention includes: a current-limiting resistor R1, a push-pull amplifier, and a drive resistor Rg; the pulse control voltage is connected to the gate of the IGBT via the series-connected current-limiting resistor R1, the push-pull amplifier, and the drive resistor Rg. The push-pull amplifier can be a prior art design, i.e., it can be referenced... Figure 1 The design of the push-pull amplifier in the existing IGBT drive protection circuit will not be elaborated here.

[0044] In a further preferred embodiment, the IGBT drive protection circuit of this invention further includes a protection module. The protection module includes a second resistor R2 connected in series and a dynamic feedback capacitor Cf. The pulse control voltage is connected to the collector of the IGBT via a current-limiting resistor R1 and the protection module.

[0045] In this way, during the turn-off process, the feedback capacitor Cf can sense the voltage change of the IGBT collector-emitter junction, forming a voltage drop VR1 across the current-limiting resistor R1, thereby increasing the gate voltage of the IGBT and protecting the drive side of the IGBT.

[0046] In a further preferred embodiment, the IGBT drive protection circuit of this invention further includes a clamping module. The clamping module includes a third resistor R3, a second diode D2, a third diode D3, and a fourth resistor R4. The pulse control voltage is connected to the gate of the IGBT via a current-limiting resistor R1, the third resistor R3, and the fourth resistor R4; the collector of the IGBT is connected to the gate of the IGBT via the second diode D2, the third diode D3, and the fourth resistor R4; the anode of diode D2 is connected to the anode of diode D3. Preferably, the resistance values ​​of the third resistor R3 and the fourth resistor R4 are equal, and preferably between 1 and 100 Ω as needed.

[0047] In this way, when the collector-emitter voltage Vce of the IGBT reaches the clamping voltage of the second diode D2, the second diode D2 turns on, and the current flows into the gate of the IGBT through the third resistor R3 and the fourth resistor R4, thereby increasing the gate voltage and further protecting the drive side of the IGBT.

[0048] In a further preferred embodiment, a second capacitor C2 is provided between the DC bus and ground potential of the IGBT drive protection circuit of this utility model, for absorbing the energy stored in each inductive element or parasitic inductance.

[0049] In a further preferred embodiment, the IGBT drive protection circuit of this invention further includes a clamping diode D1. The positive terminal of the clamping diode D1 is connected to the emitter of the IGBT; the negative terminal of the clamping diode D1 is connected to the collector of the IGBT. In this way, the collector-emitter voltage can be clamped after the collector-emitter voltage of the IGBT reaches the breakdown voltage of the clamping diode D1, thus providing further protection for the IGBT.

[0050] It should be noted that, although Figure 2 The equivalent circuit diagram shown includes a discharge module, a clamping module, and a protection module, but this is merely one possible scenario, not a limitation. In other embodiments, the IGBT drive protection circuit of this invention can select one or two modules from these three modules according to actual conditions, as long as it can achieve protection for the IGBT under high-voltage power supply.

[0051] Specifically, refer to Figure 2 Taking an IGBT drive protection circuit that simultaneously includes a discharge module, a clamping module, and a protection module as an example, the working principle of the IGBT drive protection circuit of this utility model is explained as follows: 1. First Stage: IGBT Turn-Off. The IGBT's gate voltage momentarily drops to the Miller voltage. At this time, the IGBT's collector-emitter voltage Vce and collector current remain unchanged. The Miller voltage refers to the displacement current generated on the gate due to the Miller capacitance when the IGBT's collector-emitter voltage Vce changes drastically during switching. This displacement current charges and discharges through the gate drive resistor, causing a plateau or a decrease in the rate of change of the gate voltage. The voltage value corresponding to this plateau is the Miller voltage.

[0052] 2. Second Stage: The IGBT desaturates and enters the linear region, and the collector-emitter voltage Vce begins to rise rapidly at a certain rate. During this process, the dynamic feedback capacitor Cf and the first capacitor C1 detect the change in the collector-emitter voltage, generating currents If and I1 on the dynamic feedback capacitor Cf and the first capacitor C1, respectively. At this time, the pulse control PWM voltage is at a low level, and the voltage at the front end of the push-pull output stage is 0V supplied by the PWM voltage through the first resistor R1. Most of the current If from the dynamic feedback capacitor Cf flows to the first resistor R1 through the second resistor R2, forming a voltage drop VR1 across the second resistor R2 and the first resistor R1. The current I1 generated on the first capacitor C1 flows entirely through the seventh resistor R7, forming a voltage drop VR7. During this process, VR1 increases the IGBT gate voltage through the amplification effect of the push-pull circuit in the amplification unit, reducing the IGBT collector-emitter voltage Vce. At this time, the decrease in the collector-emitter voltage causes current to be generated on the dynamic feedback capacitor Cf, further suppressing the increase of the IGBT collector-emitter voltage Vce. Simultaneously, the voltage drop VR7 across the seventh resistor R7 will generate a pulsating voltage as the voltage changes, causing the third transistor Q3 to conduct, releasing the large current at the IGBT's collector. This current is absorbed and directed to ground potential through the discharge path formed by the fifth resistor R5 and the third transistor Q3. Despite the suppression of the two circuit channels corresponding to the protection and discharge modules, the collector-emitter voltage Vce will still rise. However, after reaching the bus voltage (i.e., 820V), the IGBT's collector current and gate voltage begin to decrease. 3. Third Stage: The collector-emitter voltage Vce of the IGBT continues to rise and reaches the breakdown voltage of the clamping transistor. At this time, the clamping transistor breaks down, the collector-emitter voltage is clamped, the anti-series diode conducts, and the current flows through the third resistor R3 and the fourth resistor R4 into the gate and the front stage of the push-pull amplifier. The gate voltage increases, suppressing the continued rise of the peak voltage. At this time, the collector-emitter clamping voltage will slightly exceed the clamping voltage of the second diode D2, and its expression is: VT = VD2 + VD3 + Vg + VR4. In the formula, VD2 is the clamping voltage value of the second diode D2; VD3 is the voltage drop of the third diode; Vg is the gate voltage after being increased by the dynamic feedback capacitor Cf and the voltage clamping effect; VR4 is the voltage drop across the fourth resistor R4. During this turn-off process, the turn-off current Ioff decreases to: Ioff = Ig - Iz. The slowing down of the IGBT turn-off speed, combined with the current flowing through the third resistor R3 in the front stage, and the effect of the bleeder resistor R1 and dynamic feedback capacitor Cf, together increase the gate potential, suppressing the growth of overvoltage. The protection module also continuously absorbs and releases the voltage. Under the combined action of the protection module and the clamping module, the collector-emitter voltage Vce drops to slightly higher than the DC bus voltage (ideally equal to the DC bus voltage), effectively eliminating the oscillation problem caused by the collector-emitter voltage change, which manifests as voltage spikes in the waveform.

[0053] 4. Fourth stage: The IGBT enters the cutoff region, the current drops to 0, and finally the IGBT is turned off. When the IGBT is turned off, the energy stored on C1 is also released through the circuit of the sixth resistor R6, the third transistor Q3, the fifth resistor R5, and the seventh resistor R7 in the discharge module. The multiple diodes D7 to D11 connected in series play a positive clamping role for the third transistor Q3, while the sixth diode D6 plays a reverse protection role.

[0054] The beneficial effects of this invention are compared with those of the prior art: 1. By introducing a discharge module including a transistor, resistor, and capacitor between the collector and emitter, when the IGBT is turned off and the voltage between the emitter and collector of the IGBT exceeds a preset threshold, the emitter and collector of the transistor in the discharge module are turned on. The resistor and the transistor in the discharge module form a discharge path, discharging the current and voltage at the collector of the IGBT to ground potential. Simultaneously, the energy stored in the capacitor in the discharge module is released through the circuit formed by the resistor and the transistor.

[0055] 2. By introducing a protection circuit, a resistor is connected in series and parallel between the collector of the IGBT and the input terminal of the previous stage, so as to control the current flow and eliminate oscillation.

[0056] 3. By introducing a clamping circuit, a resistor is added to both the collector-gate of the IGBT and the front stage of the push-pull circuit to prevent the potential of the front stage of the push-pull circuit from rising and thus the gate voltage of the IGBT from rising.

[0057] This effectively enables ultra-high voltage protection for the IGBTs of 820V high-voltage air conditioning units.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of this utility model. Any modifications or equivalent substitutions that do not depart from the spirit and scope of this utility model should be covered within the protection scope of the claims of this utility model.

Claims

1. An IGBT drive protection circuit, characterized by, include: Signal amplification module, IGBT, freewheeling diode and bleeder module; The pulse control voltage is amplified by the signal amplification module and then connected to the gate of the IGBT; The emitter of the IGBT is connected to ground potential, and the collector of the IGBT is connected to the DC bus via the freewheeling diode; the load motor is connected between the collector of the IGBT and the DC bus. The discharge module includes a first capacitor, a fifth resistor, a sixth resistor, a seventh resistor, and a third transistor; the collector of the third transistor is connected to the collector of the IGBT via the fifth resistor; the emitter of the third transistor is connected to ground potential; the gate of the third transistor is connected to the collector of the IGBT via the seventh resistor and the first capacitor in series, and is connected to ground potential via the sixth resistor.

2. The IGBT drive protection circuit according to claim 1, characterized in that, When the IGBT is turned off and the voltage between the emitter and collector of the IGBT exceeds a preset threshold, the emitter and collector of the third transistor are turned on, and the fifth resistor and the third transistor form a discharge path to discharge the current and voltage of the collector of the IGBT to ground potential.

3. The IGBT drive protection circuit according to claim 1, characterized in that, When the IGBT is turned off, the energy stored in the first capacitor is released through the circuit formed by the sixth resistor, the third transistor, the fifth resistor, and the seventh resistor.

4. The IGBT drive protection circuit according to claim 1, characterized in that, The discharge module also includes a sixth diode; the positive terminal of the sixth diode is connected to ground potential, and the negative terminal is connected to the gate of the third transistor.

5. The IGBT drive protection circuit according to claim 1, characterized in that, The discharge module also includes a plurality of diodes connected in series between the base of the third transistor and the ground potential; the positive terminals of the plurality of diodes are close to the base of the third transistor, and the negative terminals of the plurality of diodes are close to the ground potential.

6. The IGBT drive protection circuit according to claim 1, characterized in that, The signal amplification module includes a current-limiting resistor, a push-pull amplifier, and a drive resistor; the pulse control voltage is connected to the gate of the IGBT via the current-limiting resistor, the push-pull amplifier, and the drive resistor connected in series.

7. The IGBT drive protection circuit according to claim 6, characterized in that, It also includes a protection module; the protection module includes a second resistor and a dynamic feedback capacitor connected in series; The pulse control voltage is connected to the collector of the IGBT in sequence via the current-limiting resistor and the protection module.

8. The IGBT drive protection circuit according to claim 6, characterized in that, It also includes a clamping module; the clamping module includes a third resistor, a second diode, a third diode, and a fourth resistor; The pulse control voltage is connected to the gate of the IGBT in sequence via a current-limiting resistor, a third resistor, and a fourth resistor; the collector of the IGBT is connected to the gate of the IGBT via a second diode, a third diode, and a fourth resistor; the anode of the second diode is connected to the anode of the third diode.

9. The IGBT drive protection circuit according to claim 1, characterized in that, A second capacitor is also provided between the DC bus and the ground potential.

10. The IGBT drive protection circuit according to claim 1, characterized in that, It also includes a clamping diode; the positive terminal of the clamping diode is connected to the emitter of the IGBT; the negative terminal of the clamping diode is connected to the collector of the IGBT.

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