High-voltage and high-current IGBT driving circuit

Abstract

This invention discloses a high-voltage, high-current IGBT driving circuit, including a first logic control circuit and a second logic control circuit, as well as an upper bridge arm optocoupler circuit, an upper bridge arm drive signal conditioning circuit, a first IGBT power transistor Q1, a lower bridge arm optocoupler circuit, a lower bridge arm drive signal conditioning circuit, and a second IGBT power transistor Q2. The upper bridge arm optocoupler circuit receives the signal from the output of the first logic control circuit. The signal is isolated and amplified by the upper bridge arm optocoupler circuit and then output to the upper bridge arm drive signal conditioning circuit. The conditioned signal is then output to the first IGBT power transistor Q1, driving Q1 to turn on and off. Based on the optocoupler device, the IGBT driving circuit achieves an IGBT turn-on voltage of 12V ≤ U. GE ≤18V, shutdown voltage -7.5V≤U GE The ≤0V driving technology requires a simple and reliable circuit that can drive 1200V, 200A IGBT power devices. To drive IGBTs with higher power, a power amplifier circuit can be added to the output of the optocoupler to enhance the driving capability and enable the driving of IGBT devices with higher power.

Description

Technical Field

[0001] This invention belongs to the field of IGBT drive control, and specifically relates to a high-voltage, high-current IGBT drive circuit. Background Technology

[0002] With the development of power devices and the increase in automation, the demand for high-voltage, high-power motor drivers is growing. Currently, the commonly used high-voltage, high-current power drive device is the IGBT. The performance of the IGBT drive circuit directly determines the switching performance and lifespan of the power transistor. Although commonly used IGBTs are equipped with corresponding driver chips, they are expensive, have complex peripheral circuits, and are not flexible in application. Moreover, most high-voltage, high-current power transistors (IGBTs) and their corresponding driver chips are imported. Summary of the Invention

[0003] The purpose of this invention is to provide a low-cost high-voltage, high-current IGBT drive circuit that utilizes common components.

[0004] The objective of this invention is achieved through the following technical means: a high-voltage, high-current IGBT drive circuit, comprising a first logic control circuit and a second logic control circuit, further comprising an upper bridge arm optocoupler circuit, an upper bridge arm drive signal conditioning circuit, a first IGBT power transistor Q1, a lower bridge arm optocoupler circuit, a lower bridge arm drive signal conditioning circuit, and a second IGBT power transistor Q2; the upper bridge arm optocoupler circuit receives the signal from the output terminal of the first logic control circuit, the signal is isolated and amplified by the upper bridge arm optocoupler circuit and then output to the upper bridge arm drive signal conditioning circuit, the conditioned signal is output to the first IGBT power transistor Q1, driving the first IGBT power transistor Q1 to turn on and off; the lower bridge arm optocoupler circuit receives the signal from the output terminal of the second logic control circuit, the signal is isolated and amplified by the lower bridge arm optocoupler circuit and then output to the lower bridge arm drive signal conditioning circuit, the conditioned signal is output to the second IGBT power transistor Q2, driving the second IGBT power transistor Q2 to turn on and off.

[0005] The upper bridge arm optocoupler circuit includes a first optocoupler device U1, a first diode D1, a third resistor R3, a fourth resistor R4, and a fifth resistor R5;

[0006] The upper bridge arm drive signal conditioning circuit includes a second diode D2, a second resistor R2, a sixth resistor R6, a first capacitor C1, and a second capacitor C2.

[0007] The second pin of the first optocoupler U1 is connected to the first common power supply;

[0008] The third pin of the first optocoupler U1 is connected to the output of the first logic control circuit.

[0009] The fifth pin of the first optocoupler U1 is grounded;

[0010] The 8th pin of the first optocoupler U1 is connected to one end of the third resistor R3 and one end of the first capacitor C1, respectively. The other end of the third resistor R3 is connected to the cathode of the first diode D1 and the first positive voltage supply terminal in sequence.

[0011] The other end of the first capacitor is grounded, and the cathode of the first diode D1 is connected in sequence to the second resistor R2 and the negative terminal of the second diode D2. The positive terminal of the second diode D2 is grounded.

[0012] One end of the second resistor R2 and the second diode D2 is also connected to the fifth resistor R5 and the second capacitor C2, and the other end of the second capacitor C2 is grounded.

[0013] The other end of the fifth resistor R5 is connected to the fourth resistor R4 and the sixth resistor R6 respectively. The other end of the fourth resistor R4 is connected to the 6th and 7th pins of the first optocoupler U1 respectively. The other end of the sixth resistor R6 is connected to the gate of the first IGBT power transistor Q1.

[0014] The source of the first IGBT power transistor Q1 is connected to the second positive voltage supply terminal;

[0015] The drain of the first IGBT power transistor Q1 is connected to the drain of the second IGBT power transistor Q2.

[0016] The lower bridge arm optocoupler circuit includes a second optocoupler device U2, a third diode D3, a ninth resistor R9, a tenth resistor R10, and an eleventh resistor R11.

[0017] The lower bridge arm drive signal conditioning circuit includes a fourth diode D4, an eighth resistor R8, a twelfth resistor R12, a third capacitor C3, and a fourth capacitor C4.

[0018] The second pin of the second optocoupler U2 is connected to the second common power supply;

[0019] The third pin of the second optocoupler U2 is connected to the output of the second logic control circuit.

[0020] The fifth pin of the second optocoupler U2 is grounded;

[0021] The 8th pin of the second optocoupler U2 is connected to one end of the ninth resistor R9 and one end of the third capacitor C3, respectively. The other end of the ninth resistor R9 is connected to the cathode of the third diode D3 and the third positive voltage supply terminal in sequence.

[0022] The other end of the first capacitor is grounded. The cathode of the third diode D3 is also connected to the eighth resistor R8 and the cathode of the fourth diode D4. The anode of the fourth diode D4 is grounded.

[0023] The eighth resistor R8 is connected to the fourth capacitor D4 at one end, and the eleventh resistor R11 and the fourth capacitor C4 are also connected to the eleventh resistor R11 and the fourth capacitor C4. The other end of the fourth capacitor C4 is grounded.

[0024] The other end of the eleventh resistor R11 is connected to the tenth resistor R10 and the twelfth resistor R12 respectively. The other end of the tenth resistor R10 is connected to the 6th and 7th pins of the second optocoupler U2 respectively. The other end of the twelfth resistor R12 is connected to the gate of the second IGBT power transistor Q2.

[0025] The source of the second IGBT power transistor Q2 is connected to the first IGBT power transistor Q1. The drain of the second IGBT power transistor Q2 is connected to the eleventh resistor R11 and the positive terminal of the fourth capacitor C4, respectively. The drain of the second IGBT power transistor Q2 is also grounded.

[0026] It also includes a protection circuit, which includes an eleventh resistor R13, a twelfth resistor R14, a fifth diode D5, a sixth diode D6, a fifth capacitor C5, and a sixth capacitor C6. The anode of the fifth diode D5 is connected to the drain of the first IGBT power transistor Q1, and the cathode of the fifth diode D5 is connected to the eleventh resistor R13 and the second positive voltage supply terminal in sequence.

[0027] The drain of the second IGBT power transistor Q2 is connected in sequence to the twelfth resistor R14 and the anode of the sixth diode D6. The cathode of the sixth diode D6 is connected to the anode of the fifth diode D5. One end of the fifth capacitor C5 is connected to the first positive voltage supply terminal, and the other end is connected to the anode of the sixth diode D6. One end of the sixth capacitor C6 is connected to the drain of the second IGBT power transistor Q2, and the other end is connected to the cathode of the fifth diode D5. The anode of the fifth diode D5 is also connected to the upper bridge arm drive signal conditioning circuit.

[0028] The second diode D2 is a Zener diode.

[0029] The fourth diode, D4, is a Zener diode.

[0030] The third pin of the first optocoupler U1 is also connected to a first resistor R1.

[0031] The third pin of the second optocoupler U2 is also connected to a seventh resistor R7.

[0032] The beneficial effects of this invention are as follows: 1. The IGBT driving circuit based on optocoupler devices achieves an IGBT turn-on voltage of 12V ≤ U. GE ≤18V, shutdown voltage -7.5V≤U GE The ≤0V driving technology requires a simple and reliable circuit. This solution can be used to drive 1200V, 200A IGBT power devices. To drive IGBTs with higher power, a power amplifier circuit can be added to the output of the optocoupler to enhance the driving capability. Combined with the pre-drive circuit principle of this solution, it is possible to drive IGBT devices with higher power.

[0033] 2. To avoid crosstalk issues caused by high voltage and high current in the control signals, the power supplies for the upper and lower bridge drive signals are independent. That is, the base power supply and ground of the six drive signals of the three sets of full-bridge IGBT modules are isolated and do not interfere with each other, and the lower bridge arm ground and the bus ground share a single ground point.

[0034] 3. A resistor and an inverting diode are connected in series and then in parallel to the collector and emitter of the IGBT. A capacitor is connected in parallel with the two diodes to form a protection circuit, which eliminates the voltage overshoot phenomenon that is easily caused when the IGBT is turned on and off. Attached Figure Description

[0035] Figure 1 Diagram of IGBT drive circuit and absorption protection circuit;

[0036] Figure 2 This is a single-channel pre-drive circuit diagram for an IGBT.

[0037] Figure 3 This is a circuit diagram for IGBT absorption protection.

[0038] Figure 4 This is a waveform diagram of the IGBT drive signal;

[0039] Figure 5 This refers to the internal structure circuit of an optocoupler.

[0040] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0041]

Example 1

[0042] like Figure 1 and Figure 2 As shown, a high-voltage, high-current IGBT drive circuit includes a first logic control circuit and a second logic control circuit, as well as an upper bridge arm optocoupler circuit, an upper bridge arm drive signal conditioning circuit, a first IGBT power transistor Q1, a lower bridge arm optocoupler circuit, a lower bridge arm drive signal conditioning circuit, and a second IGBT power transistor Q2. The upper bridge arm optocoupler circuit receives the signal from the output of the first logic control circuit. After isolation and amplification by the upper bridge arm optocoupler circuit, the signal is output to the upper bridge arm drive signal conditioning circuit. The conditioned signal is then output to the first IGBT power transistor Q1, driving Q1 to turn on and off. The lower bridge arm optocoupler circuit receives the signal from the output of the second logic control circuit. After isolation and amplification by the lower bridge arm optocoupler circuit, the signal is output to the lower bridge arm drive signal conditioning circuit. The conditioned signal is then output to the second IGBT power transistor Q2, driving Q2 to turn on and off.

[0043] The upper bridge arm optocoupler circuit includes a first optocoupler device U1, a first diode D1, a third resistor R3, a fourth resistor R4, and a fifth resistor R5;

[0044] The upper bridge arm drive signal conditioning circuit includes a second diode D2, a second resistor R2, a sixth resistor R6, a first capacitor C1, and a second capacitor C2.

[0045] The second pin of the first optocoupler U1 is connected to the first common power supply;

[0046] The third pin of the first optocoupler U1 is connected to the output of the first logic control circuit.

[0047] The fifth pin of the first optocoupler U1 is grounded;

[0048] The 8th pin of the first optocoupler U1 is connected to one end of the third resistor R3 and one end of the first capacitor C1, respectively. The other end of the third resistor R3 is connected to the cathode of the first diode D1 and the first positive voltage supply terminal in sequence.

[0049] The other end of the first capacitor is grounded, and the cathode of the first diode D1 is connected in sequence to the second resistor R2 and the negative terminal of the second diode D2. The positive terminal of the second diode D2 is grounded.

[0050] One end of the second resistor R2 and the second diode D2 is also connected to the fifth resistor R5 and the second capacitor C2, and the other end of the second capacitor C2 is grounded.

[0051] The other end of the fifth resistor R5 is connected to the fourth resistor R4 and the sixth resistor R6 respectively. The other end of the fourth resistor R4 is connected to the 6th and 7th pins of the first optocoupler U1 respectively. The other end of the sixth resistor R6 is connected to the gate of the first IGBT power transistor Q1.

[0052] The source of the first IGBT power transistor Q1 is connected to the second positive voltage supply terminal;

[0053] The drain of the first IGBT power transistor Q1 is connected to the drain of the second IGBT power transistor Q2.

[0054] The lower bridge arm optocoupler circuit includes a second optocoupler device U2, a third diode D3, a ninth resistor R9, a tenth resistor R10, and an eleventh resistor R11.

[0055] The lower bridge arm drive signal conditioning circuit includes a fourth diode D4, an eighth resistor R8, a twelfth resistor R12, a third capacitor C3, and a fourth capacitor C4.

[0056] The second pin of the second optocoupler U2 is connected to the second common power supply;

[0057] The third pin of the second optocoupler U2 is connected to the output of the second logic control circuit.

[0058] The fifth pin of the second optocoupler U2 is grounded;

[0059] The 8th pin of the second optocoupler U2 is connected to one end of the ninth resistor R9 and one end of the third capacitor C3, respectively. The other end of the ninth resistor R9 is connected to the cathode of the third diode D3 and the third positive voltage supply terminal in sequence.

[0060] The other end of the first capacitor is grounded. The cathode of the third diode D3 is also connected to the eighth resistor R8 and the cathode of the fourth diode D4. The anode of the fourth diode D4 is grounded.

[0061] The eighth resistor R8 is connected to the fourth capacitor D4 at one end, and the eleventh resistor R11 and the fourth capacitor C4 are also connected to the eleventh resistor R11 and the fourth capacitor C4. The other end of the fourth capacitor C4 is grounded.

[0062] The other end of the eleventh resistor R11 is connected to the tenth resistor R10 and the twelfth resistor R12 respectively. The other end of the tenth resistor R10 is connected to the 6th and 7th pins of the second optocoupler U2 respectively. The other end of the twelfth resistor R12 is connected to the gate of the second IGBT power transistor Q2.

[0063] The source of the second IGBT power transistor Q2 is connected to the first IGBT power transistor Q1. The drain of the second IGBT power transistor Q2 is connected to the eleventh resistor R11 and the positive terminal of the fourth capacitor C4, respectively. The drain of the second IGBT power transistor Q2 is also grounded.

[0064] The second diode D2 is a Zener diode.

[0065] The fourth diode, D4, is a Zener diode.

[0066] The third pin of the first optocoupler U1 is also connected to a first resistor R1.

[0067] The third pin of the second optocoupler U2 is also connected to a seventh resistor R7.

[0068] The driving power supply is an upper-arm optocoupler circuit and an upper-arm drive signal conditioning circuit. The first IGBT power transistor Q1 provides upper-bridge isolation power. The output of the first logic control circuit, i.e., the PWM signal output by the microprocessor chip, is input to the upper-arm optocoupler circuit. The upper-arm optocoupler circuit serves to isolate and enhance the group signal driving capability. Then, the signal is input to the upper-arm drive signal conditioning circuit, and finally input to the IGBT from the gate of the first IGBT power transistor Q1 to control the on / off state of the first IGBT power transistor Q1. The first optocoupler U1 and the second optocoupler U2 are model TLP250. In practical engineering applications, any optocoupler can be selected with an external current amplification circuit.

[0069] IGBTs combine the advantages of bipolar junction transistors (BJTs) and power MOSFETs. They are voltage-controlled devices that combine the high input impedance of MOSFETs with the low on-state voltage drop of GTRs. MOSFETs have low drive power and fast switching speed, but high on-state voltage drop and low current density; GTRs have low saturation voltage drop, high current density, and relatively large drive current. Their turn-on and turn-off are controlled by the gate-source voltage U. GE To control, when U GE Greater than the threshold voltage U GE(th) When the IGBT is turned on, it is turned off when a reverse signal or no signal is applied between the gate and emitter. However, the magnitude of the gate forward drive voltage has a significant impact on the circuit performance and must be selected correctly. In practice, its turn-on and turn-off voltages are designed to be 12V ≤ U. GE ≤18V and -7.5V≤U GE ≤0V. Ideally, the voltage VGE between the gate (G) and emitter (E) must be very steep to enable the IGBT to turn on quickly and with the shortest possible turn-on time, thus reducing turn-on losses. When the IGBT turns off, a very steep reverse forward bias voltage must be applied between G and E to enable rapid turn-off, thereby reducing dead time and improving power supply utilization. After the IGBT is turned on, the gate drive circuit must provide a sufficiently large drive voltage and current to keep the IGBT output in saturation.

[0070] The internal structure of the two optocouplers is as follows Figure 5 As shown, the model is TLP250, VCC is the circuit's power supply voltage, vo is the signal input voltage; GND is the ground wire; Tr1 and Tr2 are transformers; Vf is the feedback voltage;

[0071] Working principle of the drive circuit:

[0072] (1) When the signal output by PWM1, i.e., the output terminal of the second logic control circuit, is high, the PWM signal is 5V, the voltage drop across the optocoupler input VF is 0V, the IF current is cut off, the optocoupler LED is off, Tr1 is off, and Tr2 is on. When the PWM1 signal is low, the voltage drop across the optocoupler input VF is 5V, the IF current is on, the optocoupler LED is on, Tr1 is on, and Tr2 is off.

[0073] (2) When Tr1 is closed, it is equivalent to Tr1 being disconnected. When Tr2 is open, it is equivalent to Tr2 being short-circuited. The input level of the fourth resistor R4 is close to ground. Since the IGBT power transistor is connected between the HO1 terminal and the P_A terminal, the IGBT transistor can be regarded as a capacitor. Under the action of the 7.5V Zener diode, it is equivalent to a 7.5V voltage drop between the HO1 terminal and the P_A terminal. At this time, when the IGBT power transistor has a momentary positive 7.5V voltage, it can be regarded as a capacitor short circuit. At this time, a 7.5V voltage is applied to the fourth resistor R4 terminal. The fourth resistor R4 is selected as 15 ohms. The instantaneous current on the fourth resistor R4 is 0.5A, which is consistent with the description of the optocoupler TLP250.

[0074] When the IGBT (capacitor) is charged to saturation, the voltage at the P_A terminal is 7.5V. After voltage division by the fifth resistor R5 with a resistance of 1K and the fourth resistor R4 with a resistance of 15 ohms, the voltage across the resistor R5 is 7.39V according to formula (1).

[0075]

[0076] That is, the output voltage between HO1 and P_A is -7.39V, at which point the IGBT controlled by HO1 can be completely turned off. The capacitor charging time is related to the IGBT junction capacitance, and resistor R5 plays a role in both releasing and charging.

[0077] (3) When Tr2 is off, it is equivalent to Tr2 being open; when Tr1 is on, it is equivalent to Tr1 being short-circuited.

[0078] The input voltage of the fourth resistor R4 is the voltage value after the power supply VCC is divided by the third resistor R3. Since the IGBT power transistor is connected between the HO1 terminal and the P_A terminal, the IGBT transistor can be regarded as a capacitor. Under the action of the 7.5V Zener diode, a 7.5V voltage drop is generated between the HO1 terminal and the P_A terminal. At this time, when the IGBT momentarily has a positive 7.5V voltage, it can be regarded as a capacitor short circuit. At this time, the maximum current I output by the fourth resistor R4 is... R4 The current is approximately 0.47A according to formula (2), which is basically consistent with the maximum peak current of 0.5A described in the TLP250 datasheet.

[0079]

[0080] When the IGBT (capacitor) is charged to saturation, the voltage at the P_A terminal is 7.5V. After voltage division by the fifth resistor R5 with a resistance of 1K and the fourth resistor R4 with a resistance of 15 ohms, the voltage across the fifth resistor R5 is 16.256V according to formula (3).

[0081]

[0082] That is, the output voltage between the HO1 terminal and the P_A terminal is +16.256V, at which point the IGBT controlled by HO1 is turned on. The capacitor charging time is related to the IGBT junction capacitance, and the fifth resistor R5 plays a role in charging and discharging.

[0083] The same applies to the lower bridge arm drive circuit.

[0084] The solution achieves an IGBT turn-on voltage of 12V ≤ U GE ≤18V, shutdown voltage -7.5V≤U GE For drive technology requirements of ≤0V, the drive signal waveform should be as follows: Figure 4 As shown in the figure, the voltage amplitude is 5.00V / div.

[0085]

Example 2

[0086] like Figure 1 and Figure 3 As shown, it also includes a protection circuit, which includes an eleventh resistor R13, a twelfth resistor R14, a fifth diode D5, a sixth diode D6, a fifth capacitor C5, and a sixth capacitor C6. The anode of the fifth diode D5 is connected to the drain of the first IGBT power transistor Q1, and the cathode of the fifth diode D5 is connected to the eleventh resistor R13 and the second positive voltage supply terminal in sequence.

[0087] The drain of the second IGBT power transistor Q2 is connected in sequence to the twelfth resistor R14 and the anode of the sixth diode D6. The cathode of the sixth diode D6 is connected to the anode of the fifth diode D5. One end of the fifth capacitor C5 is connected to the first positive voltage supply terminal, and the other end is connected to the anode of the sixth diode D6. One end of the sixth capacitor C6 is connected to the drain of the second IGBT power transistor Q2, and the other end is connected to the cathode of the fifth diode D5. The anode of the fifth diode D5 is also connected to the upper bridge arm drive signal conditioning circuit. The anode of the fifth diode D5 is connected to the end of the second resistor R2 that is connected to the second diode D2.

[0088] Due to the presence of parasitic inductance, when the second IGBT power transistor Q2 is turned off, the load current cannot change immediately. The upper arm freewheeling diode conducts, and at this time, the parasitic inductance generates a voltage that, combined with the bus voltage, surges across the lower arm IGBT. This voltage can easily exceed VCES and cause damage. To address this, an absorption protection circuit is added. When the voltage at the P_A terminal surges and exceeds the second positive voltage supply terminal VCC_M, the fifth diode D5 quickly resumes conduction, rapidly reducing the VCE voltage across D5 to stabilize and suppress voltage fluctuations. If the bus voltage VCC_M surges, resistor R13 and capacitor C6 are connected in series across the bus. This series connection of resistor and capacitor blocks DC and passes AC, and passes high frequencies while blocking low frequencies. Here, their delay function is primarily used to mitigate the damage caused by sudden voltage changes to the IGBT, thus improving the voltage and current waveforms experienced by the IGBT power transistor during turn-on and turn-off. Similarly, when the second IGBT power transistor Q2 is turned on, the freewheeling current is transferred to the second IGBT power transistor Q2 and decreases. When it recovers, the parasitic inductance in the circuit will also generate a surge voltage, which is given by formula (4), where LP is the parasitic inductance. denoted as the rate of change of current.

[0089]

[0090] Based on the DC bus voltage VCC_M and the IGBT power transistor emitter voltage V CE The voltage relationship across the inductor is given in formula (5).

[0091] V CE =(VCC_M-V L (V) (5)

[0092] It is evident that the presence of this parasitic inductance makes the IGBT prone to voltage overshoot during turn-on and turn-off. To eliminate this surge voltage, the protection circuit involved in this case consists of a resistor and an inverting diode connected in series and then connected in parallel to the source and drain of the IGBT, and a capacitor connected in parallel with the resistor and the two diodes. Since the voltage and current between the emitter and the electrode of the IGBT power transistor change abruptly when the IGBT is turned on and off, the series resistor and capacitor in the protection circuit will delay the voltage surge at the moment of turn-on. At the moment of turn-off, the freewheeling current of the inverting diode and the absorption function of the series resistor will also delay the voltage surge, thus achieving the function of protecting the IGBT.

Claims

1. A high-voltage, high-current IGBT drive circuit, comprising a first logic control circuit and a second logic control circuit, characterized in that: It also includes an upper bridge arm optocoupler circuit, an upper bridge arm drive signal conditioning circuit, a first IGBT power transistor Q1, a lower bridge arm optocoupler circuit, a lower bridge arm drive signal conditioning circuit, and a second IGBT power transistor Q2. The upper bridge arm optocoupler circuit receives the signal from the output of the first logic control circuit. After the signal is isolated and amplified by the upper bridge arm optocoupler circuit, it is output to the upper bridge arm drive signal conditioning circuit. The conditioned signal is then output to the first IGBT power transistor Q1, driving the first IGBT power transistor Q1 to turn on and off. The lower bridge arm optocoupler circuit receives the signal from the output of the second logic control circuit. After the signal is isolated and amplified by the lower bridge arm optocoupler circuit, it is output to the lower bridge arm drive signal conditioning circuit. The conditioned signal is then output to the second IGBT power transistor Q2, driving the second IGBT power transistor Q2 to turn on and off. It also includes a protection circuit, which includes a thirteenth resistor R13, a fourteenth resistor R14, a fifth diode D5, a sixth diode D6, a fifth capacitor C5, and a sixth capacitor C6. The cathode of the fifth diode D5 is connected in sequence to the thirteenth resistor R13 and the second positive voltage supply terminal. The drain of the second IGBT power transistor Q2 is connected in sequence to the fourteenth resistor R14 and the anode of the sixth diode D6. The cathode of the sixth diode D6 is connected to the anode of the fifth diode D5. One end of the fifth capacitor C5 is connected to the second positive voltage supply terminal, and the other end is connected to the anode of the sixth diode D6. One end of the sixth capacitor C6 is connected to the drain of the second IGBT power transistor Q2, and the other end is connected to the cathode of the fifth diode D5. The anode of the fifth diode D5 is also connected to the upper bridge arm drive signal conditioning circuit. The upper bridge arm optocoupler circuit includes a first optocoupler device U1, a first diode D1, a third resistor R3, a fourth resistor R4, and a fifth resistor R5; The upper bridge arm drive signal conditioning circuit includes a second diode D2, a second resistor R2, a sixth resistor R6, a first capacitor C1, and a second capacitor C2. The second pin of the first optocoupler U1 is connected to the first common power supply; The third pin of the first optocoupler U1 is connected to the output of the first logic control circuit. The fifth pin of the first optocoupler U1 is connected to the bridge arm signal ground; The 8th pin of the first optocoupler U1 is connected to one end of the third resistor R3 and one end of the first capacitor C1, respectively. The other end of the third resistor R3 is connected to the cathode of the first diode D1 and the first positive voltage supply terminal in sequence. The other end of the first capacitor C1 is connected to the bridge arm signal ground. The cathode of the first diode D1 is also connected to the second resistor R2 and the cathode of the second diode D2 in sequence. The anode of the second diode D2 is connected to the bridge arm signal ground. One end of the second resistor R2 and the second diode D2 is also connected to the fifth resistor R5 and the second capacitor C2. The other end of the second capacitor C2 is connected to the bridge arm signal ground. The other end of the fifth resistor R5 is connected to the fourth resistor R4 and the sixth resistor R6 respectively. The other end of the fourth resistor R4 is connected to the 6th and 7th pins of the first optocoupler U1 respectively. The other end of the sixth resistor R6 is connected to the gate of the first IGBT power transistor Q1. The source of the first IGBT power transistor Q1 is connected to the second positive voltage supply terminal; The drain of the first IGBT power transistor Q1 is connected to the source of the second IGBT power transistor Q2. The anode of the fifth diode D5 is connected to the end of the second resistor R2 that is connected to the second diode D2.

2. The high-voltage, high-current IGBT drive circuit according to claim 1, characterized in that: The lower bridge arm optocoupler circuit includes a second optocoupler device U2, a third diode D3, a ninth resistor R9, a tenth resistor R10, and an eleventh resistor R11. The lower bridge arm drive signal conditioning circuit includes a fourth diode D4, an eighth resistor R8, a twelfth resistor R12, a third capacitor C3, and a fourth capacitor C4; The second pin of the second optocoupler U2 is connected to the second common power supply; The third pin of the second optocoupler U2 is connected to the output of the second logic control circuit. The fifth pin of the second optocoupler U2 is connected to the lower bridge arm signal ground; The 8th pin of the second optocoupler U2 is connected to one end of the ninth resistor R9 and one end of the third capacitor C3, respectively. The other end of the ninth resistor R9 is connected to the cathode of the third diode D3 and the third positive voltage supply terminal in sequence. The other end of the third capacitor C3 is connected to the lower bridge arm signal ground. The cathode of the third diode D3 is also connected to the eighth resistor R8 and the cathode of the fourth diode D4 in sequence. The anode of the fourth diode D4 is connected to the lower bridge arm signal ground. The eighth resistor R8 is connected to the fourth diode D4 at one end, which is also connected to the eleventh resistor R11 and the fourth capacitor C4. The other end of the fourth capacitor C4 is connected to the lower bridge arm signal ground. The other end of the eleventh resistor R11 is connected to the tenth resistor R10 and the twelfth resistor R12 respectively. The other end of the tenth resistor R10 is connected to the 6th and 7th pins of the second optocoupler U2 respectively. The other end of the twelfth resistor R12 is connected to the gate of the second IGBT power transistor Q2. The source of the second IGBT power transistor Q2 is connected to the drain of the first IGBT power transistor Q1. The drain of the second IGBT power transistor Q2 is connected to the eleventh resistor R11 and the positive terminal of the fourth capacitor C4, respectively. The drain of the second IGBT power transistor Q2 is also connected to the second ground.

3. The high-voltage, high-current IGBT drive circuit according to claim 1, characterized in that: The second diode D2 is a Zener diode.

4. The high-voltage, high-current IGBT drive circuit according to claim 2, characterized in that: The fourth diode, D4, is a Zener diode.

5. The high-voltage, high-current IGBT drive circuit according to claim 1, characterized in that: The third pin of the first optocoupler U1 is also connected to a first resistor R1.

6. The high-voltage, high-current IGBT drive circuit according to claim 2, characterized in that: The third pin of the second optocoupler U2 is also connected to a seventh resistor R7.

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