CN220401994U

CN220401994U - IGBT driving circuit and electromagnetic heating equipment

Info

Publication number: CN220401994U
Application number: CN202321908653.0U
Authority: CN
Inventors: 冯红涛; 樊光民; 王强; 汪钊; 张涛; 陈虎; 吴焯然
Original assignee: Chunmi Technology Shanghai Co Ltd
Current assignee: Chunmi Technology Shanghai Co Ltd
Priority date: 2023-07-19
Filing date: 2023-07-19
Publication date: 2024-01-26
Anticipated expiration: 2033-07-19

Abstract

The utility model discloses an IGBT driving circuit and electromagnetic heating equipment, which are applied to the technical field of power electronics and are used for solving the problem that in the prior art, an IGBT is damaged due to overhigh collector voltage at the moment of switching on the IGBT, and specifically comprise the following steps: the first end of the voltage-stabilizing diode module is connected to the wiring of the second end of the driving module and the grid electrode of the external IGBT, and the second end of the voltage-stabilizing diode module is connected with the first end of the on-off control module; the second end of the on-off control module is connected with the second end of the external controller, and the third end of the on-off control module is connected with the ground; when the collector voltage is too high at the turn-on instant of the IGBT, the initial voltage of the driving signal may be stabilized to the first voltage. Therefore, the method reduces the turn-on speed of the IGBT by reducing the initial voltage of the driving signal, ensures that the peak current is reduced at the moment of switching on the IGBT, and avoids damaging the IGBT.

Description

IGBT driving circuit and electromagnetic heating equipment

Technical Field

The utility model relates to the technical field of power electronics, in particular to an IGBT driving circuit and electromagnetic heating equipment.

Background

The electromagnetic heating equipment is an electric appliance which converts electric energy into heat energy by utilizing an electromagnetic induction principle, and an electromagnetic oven and an electric cooker are common electromagnetic heating equipment. Electromagnetic heating devices typically consist of an inductance and a capacitance to resonate and are controlled by an IGBT (Insulated Gate Bipolar Transistor ) on and off to perform resonant heating.

At present, the IGBT of electromagnetic heating equipment is turned on instantly, the condition that the collector voltage of the IGBT is too high exists, so that the IGBT is turned on quickly, the current peak value at the moment of the IGBT is higher, the IGBT is easy to damage, and noise is generated.

Disclosure of Invention

The embodiment of the utility model provides an IGBT driving circuit and electromagnetic heating equipment, which are used for solving the problem that an IGBT is damaged due to over-high collector voltage at the moment of switching on the IGBT in the prior art.

The technical scheme provided by the embodiment of the utility model is as follows:

in one aspect, an embodiment of the present utility model provides an IGBT driving circuit, including: the device comprises a voltage-stabilizing diode module, a driving module, an on-off control module and a power supply module;

the first end of the driving module is connected with the first end of the external controller, the second end of the driving module is connected with the grid electrode of the external IGBT, and the third end of the driving module is connected with the power supply module; the driving module is used for generating driving signals according to signals input by the external controller;

the first end of the zener diode module is connected to the wiring between the second end of the driving module and the grid electrode of the external IGBT, and the second end of the zener diode module is connected with the first end of the on-off control module; the second end of the on-off control module is connected with the second end of the external controller, and the third end of the on-off control module is connected with the ground; the on-off control module is used for connecting or disconnecting the voltage-stabilizing diode module with the ground; the zener diode module is used for stabilizing the initial voltage of the driving signal to the first voltage when the second end of the zener diode module is grounded and the initial voltage of the driving signal is larger than the first voltage.

In one possible implementation, the zener diode module includes: at least one zener diode;

the cathode of the first one of the at least one zener diode is connected to the second end of the driving module and the connection line of the grid electrode of the external IGBT, the anode of the last one of the at least one zener diode is connected with the first end of the on-off control module, the cathode of each one of the at least one zener diode is connected with the anode of the previous one of the at least one zener diode, and the anode of each one of the at least one zener diode is connected with the cathode of the next one of the at least one zener diode.

In one possible embodiment, the driving module includes: the driving circuit comprises a first resistor, a driving chip and a waveform adjusting module;

the input end of the driving chip is connected with the first end of the external controller through the first resistor, the power supply end of the driving chip is connected with the power supply module, and the output end of the driving chip is connected with the first end of the waveform adjusting module;

the second end of the waveform adjusting module is connected with the grid electrode of the external IGBT; the waveform adjusting module is used for adjusting rising edges and falling edges of the driving signals.

In one possible implementation, the waveform adjustment module includes: the second resistor, the third resistor and the first diode;

the first end of the second resistor is connected with the output end of the driving chip, and the second end of the second resistor is connected with the grid electrode of the external IGBT;

the first end of the third resistor is connected with the cathode of the first diode, and the second end of the third resistor is connected with the second end of the second resistor; the anode of the first diode is connected with the first end of the second resistor.

In one possible embodiment, the power module includes: the direct-current power supply, the first capacitor and the electrolytic capacitor;

the positive electrode of the electrolytic capacitor is respectively connected with the direct-current power supply and the power supply end of the driving chip, and the negative electrode of the electrolytic capacitor is respectively connected with the ground and the ground end of the driving chip;

the first end of the first capacitor is connected with the positive electrode of the electrolytic capacitor, and the second end of the first capacitor is connected with the negative electrode of the electrolytic capacitor.

In one possible implementation, the on-off control module includes: the first triode, the fourth resistor, the fifth resistor, the sixth resistor and the second capacitor;

the base electrode of the first triode is connected with the second end of the external controller through a fourth resistor, the collector electrode of the first triode is connected with the second end of the zener diode module through a fifth resistor, and the emitter electrode of the first triode is connected with the ground;

the sixth resistor is connected with the second capacitor in parallel, one connecting node is connected with the base electrode of the first triode, and the other connecting node is grounded.

In one possible embodiment, the IGBT driving circuit further includes: a protection module;

the first end of the protection module is connected with the first end of the zener diode module and the grid electrode of the external IGBT respectively, and the second end of the protection module is connected with the emitter electrode of the external IGBT; the protection module is used for stabilizing the voltage between the grid electrode and the emitter electrode of the external IGBT to a second voltage.

In one possible implementation, the protection module includes: a first zener diode and a seventh resistor;

the anode of the first zener diode is connected with the emitter of the external IGBT, and the cathode of the zener diode is respectively connected with the first end of the zener diode module and the grid electrode of the external IGBT;

the first end of the seventh resistor is connected with the positive electrode of the first voltage stabilizing diode, and the second end of the seventh resistor is connected with the negative electrode of the first voltage stabilizing diode.

In another aspect, an embodiment of the present utility model provides an electromagnetic heating apparatus, including: the IGBT driving circuit, the main circuit, the controller and the synchronous hardware circuit provided by the embodiment of the utility model;

the first end of the IGBT driving circuit is connected with the grid electrode of the IGBT in the main circuit, the second end of the IGBT driving circuit is connected with the first end of the controller, and the third end of the IGBT driving circuit is connected with the second end of the controller;

the first end of the synchronous hardware circuit is connected with the second end of the main circuit, and the second end of the synchronous hardware circuit is connected with the third end of the controller.

In one possible implementation, the main circuit includes: the device comprises an EMI filter circuit, a rectifier circuit, a filter capacitor, an LC resonant circuit and an IGBT;

the first end of the EMI filter circuit is connected with an external power supply, and the second end of the EMI filter circuit is connected with the first end of the rectifying circuit;

the second end of the rectifying circuit is respectively connected with the first end of the LC resonant circuit and the first end of the filter capacitor, and the third end of the rectifying circuit is respectively connected with the emitter of the IGBT and the second end of the filter capacitor;

the second end of the LC resonance circuit is connected with the collector of the IGBT, and the third end of the LC resonance circuit is connected with the first end of the synchronous hardware circuit; the gate of the IGBT is connected with a first end of the IGBT driving circuit.

The embodiment of the utility model has the following beneficial effects:

in the embodiment of the utility model, the first end of the voltage-stabilizing diode module is connected to the wiring between the second end of the driving module and the grid electrode of the external IGBT, and the second end of the voltage-stabilizing diode module is connected with the first end of the on-off control module; the second end of the on-off control module is connected with the second end of the external controller, and the third end of the on-off control module is connected with the ground; when the collector voltage is too high at the moment of switching on the IGBT, the initial voltage of the driving signal can be stabilized to the first voltage, and the switching-on speed of the IGBT is reduced in a mode of reducing the initial voltage of the driving signal, so that the peak current at the moment of switching on the IGBT is reduced, and damage to the IGBT is avoided.

Additional features and advantages of the utility model will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model. The objectives and other advantages of the utility model will be realized and attained by the structure particularly pointed out in the written description and claims thereof as well as the appended drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description serve to explain the utility model and do not constitute a limitation on the utility model. In the drawings:

fig. 1 is a schematic diagram of a first circuit structure of an IGBT driving circuit according to an embodiment of the present utility model;

fig. 2 is a schematic diagram of a second circuit structure of an IGBT driving circuit according to an embodiment of the present utility model;

fig. 3 is a schematic diagram of a third circuit structure of an IGBT driving circuit according to an embodiment of the present utility model;

fig. 4 is a schematic diagram of a fourth circuit structure of an IGBT driving circuit according to an embodiment of the present utility model;

fig. 5 is a schematic diagram of a fifth circuit structure of an IGBT driving circuit according to an embodiment of the utility model;

fig. 6 is a schematic diagram of a sixth circuit structure of an IGBT driving circuit according to an embodiment of the utility model;

fig. 7 is a schematic diagram of a seventh circuit structure of an IGBT driving circuit according to an embodiment of the utility model;

fig. 8 is a schematic diagram of an eighth circuit structure of an IGBT driving circuit according to an embodiment of the utility model;

fig. 9 is a schematic view of a first structure of an electromagnetic heating apparatus according to an embodiment of the present utility model;

fig. 10 is a schematic diagram of a second structure of an electromagnetic heating apparatus according to an embodiment of the present utility model.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments, but not all embodiments of the present utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

An embodiment of the present utility model provides an IGBT driving circuit, referring to fig. 1, the IGBT driving circuit 100 is characterized by comprising: a zener diode module 110, a driving module 120, an on-off control module 130, and a power module 140;

a first end of the driving module 120 is connected with a first end of an external controller, a second end of the driving module 120 is connected with a grid electrode of an external IGBT, and a third end of the driving module 120 is connected with the power supply module 140; the driving module 120 is used for generating a driving signal according to a signal input by an external controller;

the first end of the zener diode module 110 is connected to the connection between the second end of the driving module 120 and the gate of the external IGBT, and the second end of the zener diode module 110 is connected to the first end of the on-off control module 130; the second end of the on-off control module 130 is connected with the second end of the external controller, and the third end of the on-off control module 130 is connected with the ground; the on-off control module 130 is used for switching on or switching off the connection between the zener diode module 110 and the ground; the zener diode module 110 is configured to stabilize the initial voltage of the driving signal to the first voltage when the second terminal of the zener diode module 110 is grounded and the initial voltage of the driving signal is greater than the first voltage.

In practical applications, the power module 140 is configured to supply power to the driving module 120, and after the driving module 120 receives a signal input by the external controller, it outputs a driving signal with the same period and duty ratio as those of the signal input by the external controller, but different voltages. The initial voltage of the driving signal output by the driving module 120 is generally equal to the voltage provided by the power module 140. Because the collector voltage of the IGBT is too high, the IGBT is controlled according to the driving signal currently output by the driving module 120, so that the IGBT is turned on at a fast speed, resulting in a higher current peak at the moment of IGBT turn-on and easy damage to the IGBT, so that at the moment of IGBT turn-on, the on-off control module 130 receives a corresponding control signal input by the external controller, and turns on the connection between the zener diode module 110 and ground, so that when the initial voltage of the driving signal is greater than the first voltage, the zener diode module 110 stabilizes the initial voltage of the driving signal to the first voltage and then transmits the first voltage to the gate of the IGBT. The first voltage is a voltage value that can ensure that the IGBT is turned on and is lower than an initial voltage of the driving signal, and the voltage value is generally a voltage stabilizing value of the zener diode module 110. Therefore, the method reduces the turn-on speed of the IGBT by reducing the initial voltage of the driving signal, ensures that the peak current is reduced at the moment of switching on the IGBT, and avoids damaging the IGBT. In the normal operation of the IGBT, the on-off control module 130 receives a corresponding control signal input from the external controller, disconnects the zener diode module 110 from the ground, and the driving signal output from the driving module 120 is directly input to the gate of the IGBT without being stabilized by the zener diode module 110. Therefore, the IGBT can be ensured to keep a good conduction speed during normal operation.

In specific implementation, in the IGBT driving circuit 100 provided in the embodiment of the present application, the zener diode module 110 may have various specific structures to implement the functions thereof. As shown in fig. 2, for example, the zener diode module 110 includes: at least one zener diode;

the cathode of the first one of the at least one zener diode is connected to the connection between the second end of the driving module 120 and the gate of the external IGBT, the anode of the last one of the at least one zener diode is connected to the first end of the on-off control module 130, the cathode of each of the at least one zener diode is connected to the anode of the previous one, and the anode of each of the at least one zener diode is connected to the cathode of the next one.

In practical applications, the zener diode module 110 is mainly composed of at least one zener diode. The sum of the regulated values of the at least one zener diode is equal to the first voltage. When the initial voltage of the driving signal is higher than the first voltage, the zener diode in the zener diode module 110 breaks down and stabilizes the initial voltage of the driving signal to the first voltage. The model number and the number of the zener diodes in the zener diode module 110 can be determined according to the value of the first voltage. If the first voltage value is equal to the voltage value of the voltage stabilizing diode of the corresponding model, a voltage stabilizing diode can be arranged in the voltage stabilizing diode module 110; if the first voltage value is larger, the plurality of zener diodes are required to be connected in series in sequence, so that the sum of the voltage stabilizing values of the plurality of zener diodes is equal to the first voltage. In addition, the selection of the zener diode is not limited herein, and other factors such as current in the circuit are also considered.

In specific implementation, in the IGBT driving circuit 100 provided in the embodiment of the present application, the driving module 120 may have various specific structures to implement the functions thereof. As shown in fig. 3, for example, the driving module 120 includes: a first resistor R1, a driving chip 121, and a waveform adjusting module 122;

the input end of the driving chip 121 is connected with the first end of the external controller through a first resistor R1, the power supply end of the driving chip 121 is connected with the power supply module 140, and the output end of the driving chip 121 is connected with the first end of the waveform adjusting module 122;

a second end of the waveform adjusting module 122 is connected with a grid electrode of the external IGBT; the waveform adjusting module 122 is used for adjusting rising edges and falling edges of the driving signals.

In practical applications, the first resistor R1 is generally used for adjusting the current input to the driving chip 121 to prevent the driving chip 121 from being damaged due to excessive current. The driving chip 121 is used for receiving signals input by an external controller and generating driving signals according to the signals input by the external controller. The waveform adjusting module 122 is mainly used for adjusting the rising edge and the falling edge of the driving signal through the resistance change on the line.

In particular implementations, to achieve rising and falling edges of a drive signal input to an IGBT to improve EMI (Electromagnetic Interference ) in a circuit, referring to fig. 4, the waveform adjustment module 122 includes: a second resistor R2, a third resistor R3 and a first diode D1;

the first end of the second resistor R2 is connected with the output end of the driving chip 121, and the second end of the second resistor R2 is connected with the grid electrode of the external IGBT;

the first end of the third resistor R3 is connected with the cathode of the first diode D1, and the second end of the third resistor R3 is connected with the second end of the second resistor R2; the anode of the first diode D1 is connected to the first end of the second resistor R2.

In practical application, when the driving signal output from the output terminal of the driving chip 121 becomes high level, the first diode is turned on, at this time, the impedance of the line between the output terminal of the driving chip 121 and the gate of the external IGBT is the impedance obtained by connecting the second resistor R2 and the third resistor R3 in parallel, and the voltage input to the gate of the IGBT increases from 0V to 18V under the effect of the impedance obtained by connecting the second resistor R2 and the third resistor R3 in parallel. When the driving signal output from the output terminal of the driving chip 121 becomes low level, the first diode is not turned on, and at this time, the impedance of the line between the output terminal of the driving chip 121 and the gate of the external IGBT is the second resistor R2, and the voltage input to the gate of the IGBT drops from 18V to 0V by the second resistor R2. By adjusting the magnitudes of the second resistor R2 and the third resistor R3 in the circuit, the speed at which the voltage input to the gate of the IGBT rises or falls, i.e., the rising and falling edges of the drive signal input to the IGBT can be adjusted. When the second resistor R2 and the third resistor R3 are increased at the same time, the speed at which the voltage input to the gate of the IGBT rises and falls becomes slow, and when the second resistor R2 is increased, the speed at which the voltage input to the gate of the IGBT falls becomes slow.

In specific implementation, in the IGBT driving circuit 100 provided in the embodiment of the present application, the power module 140 may have various specific structures to implement the functions thereof. As shown in fig. 5, for example, the power module 140 includes: a direct current power supply VCC, a first capacitor C1 and an electrolytic capacitor EC1;

the positive electrode of the electrolytic capacitor EC1 is respectively connected with the direct-current power supply VCC and the power supply end of the driving chip 121, and the negative electrode of the electrolytic capacitor EC1 is respectively connected with the ground and the grounding end of the driving chip 121;

the first end of the first capacitor C1 is connected with the positive electrode of the electrolytic capacitor EC1, and the second end of the first capacitor C1 is connected with the negative electrode of the electrolytic capacitor EC 1.

In practical application, the dc power VCC is used for providing dc power, and the magnitude of the dc power needs to be determined according to the type of the driving chip 121 and the driving condition of the IGBT, and is generally 18V; the first capacitor C1 and the electrolytic capacitor EC1 mainly play a role in filtering the input direct current, and provide the filtered direct current to the driving chip 121.

In specific implementation, in the IGBT driving circuit 100 provided in the embodiment of the present application, the on-off control module 130 may have various specific structures to implement the functions thereof. For example, as shown in fig. 6, the on-off control module 130 includes: the first triode Q1, the fourth resistor R4, the fifth resistor R5, the sixth resistor R6 and the second capacitor C2;

the base electrode of the first triode Q1 is connected with the second end of the external controller through a fourth resistor R4, the collector electrode of the first triode Q1 is connected with the second end of the zener diode module 110 through a fifth resistor R5, and the emitter electrode of the first triode Q1 is connected with the ground;

the sixth resistor R6 is connected in parallel with the second capacitor C2, and one connection node is connected to the base of the first triode Q1, and the other connection node is grounded.

In practical applications, the second capacitor C2 is used for filtering the voltage input to the first transistor Q1, and the fifth resistor R5 is generally used for adjusting the current input to the collector of the first transistor Q1 to prevent the first transistor Q1 from being damaged due to excessive current. The fourth resistor R4 and the sixth resistor R6 form a bias voltage divider circuit, and step down the voltage input from the second end of the external controller to the driving voltage of the first triode Q1, so that the first triode Q1 is connected to or disconnected from the zener diode module 110 under the control of the external controller.

In one possible implementation, referring to fig. 7, the IGBT driving circuit 100 provided in the embodiment of the present application further includes: a protection module 150;

the first end of the protection module 150 is connected with the first end of the zener diode module 110 and the grid electrode of the external IGBT respectively, and the second end of the protection module 150 is connected with the emitter electrode of the external IGBT; the protection module 150 is used to stabilize the voltage of the gate of the external IGBT to the second voltage.

In practical application, in order to prevent interference caused by spike voltage, the protection module 150 is configured to stabilize the voltage between the gate and the emitter of the external IGBT to the second voltage, and in particular, in the IGBT driving circuit 100 provided in the embodiment of the present application, the protection module 150 may have a plurality of specific structures to implement the functions thereof. As shown in fig. 8, for example, the protection module 150 includes: a first zener diode ZD1 and a seventh resistor R7;

the anode of the first zener diode ZD1 is connected with the emitter of the external IGBT, and the cathode of the zener diode is connected with the first end of the zener diode module 110 and the gate of the external IGBT, respectively;

the first end of the seventh resistor R7 is connected to the positive electrode of the first zener diode ZD1, and the second end of the seventh resistor R7 is connected to the negative electrode of the first zener diode ZD 1.

In practical applications, the second voltage is generally set to be the initial voltage of the driving signal output by the driving chip 121. The voltage stabilizing value of the first zener diode ZD1 is a second voltage, and when there is a spike voltage, the first zener diode ZD1 breaks down to stabilize the voltage of the gate of the external IGBT to the second voltage.

Based on the same concept, the embodiment of the present utility model further provides an electromagnetic heating apparatus, referring to fig. 9, including: the embodiment of the present utility model provides the above IGBT driving circuit 100, the main circuit 210, the controller 220, and the synchronization hardware circuit 230;

a first end of the IGBT driving circuit 100 is connected to the gate of the IGBT in the main circuit 210, a second end of the IGBT driving circuit 100 is connected to the first end of the controller 220, and a third end of the IGBT driving circuit 100 is connected to the second end of the controller 220;

a first terminal of the synchronization hardware circuit 230 is connected to a second terminal of the main circuit 210, and a second terminal of the synchronization hardware circuit 230 is connected to a third terminal of the controller 220.

In practical applications, the synchronous hardware circuit 230 may collect the working condition of the LC resonant circuit 213 in the main circuit 210, so that the controller 220 determines the driving signal and determines whether there is an excessively high collector voltage of the IGBT, if so, the IGBT driving circuit 100 is controlled to stabilize the initial voltage of the driving signal to the first voltage at the moment of turning on the IGBT, and then the initial voltage is transmitted to the gate of the IGBT. If not, the driving signal output by the driving module is directly input to the grid electrode of the IGBT.

In one possible embodiment, referring to fig. 10, the main circuit 210 of the electromagnetic heating apparatus 200 includes at least: an EMI filter circuit 211, a rectifier circuit 212, a filter capacitor Cin, an LC resonance circuit 213, and an IGBT;

a first end of the EMI filter circuit 211 is connected to an external power source, and a second end of the EMI filter circuit 211 is connected to a first end of the rectifier circuit 212;

the second end of the rectifying circuit 212 is respectively connected with the first end of the LC resonant circuit 213 and the first end of the filter capacitor Cin, and the third end of the rectifying circuit 212 is respectively connected with the emitter of the IGBT and the second end of the filter capacitor Cin;

a second terminal of LC resonant circuit 213 is connected to the collector of the IGBT, and a third terminal of LC resonant circuit 213 is connected to a first terminal of synchronization hardware circuit 230; the gate of the IGBT is connected to a first terminal of the IGBT drive circuit 100.

In practice, the LC resonant circuit 213 is generally formed by parallel connection of an inductance and a capacitance. The rectifying circuit 212 is a rectifying bridge. The main circuit 210 may be additionally provided with a voltage sampling circuit, a voltage surge circuit, and a temperature sampling circuit. The output terminals of the voltage sampling circuit, the voltage surge circuit and the temperature sampling circuit are connected with the controller 220, so that the controller 220 determines the voltage, the voltage surge and the temperature conditions of the circuit.

In the electromagnetic heating device provided by the embodiment of the utility model, the IGBT driving circuit can avoid the condition that the IGBT is damaged due to the over-voltage of the collector electrode at the moment of switching on the IGBT, so the electromagnetic heating device using the IGBT driving circuit also has the corresponding advantages, and the details are not repeated here.

While preferred embodiments of the present utility model have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the utility model.

It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the present utility model without departing from the spirit or scope of the embodiments of the utility model. Thus, if such modifications and variations of the embodiments of the present utility model fall within the scope of the claims and the equivalents thereof, the present utility model is also intended to include such modifications and variations.

Claims

1. An IGBT drive circuit, comprising: the device comprises a voltage-stabilizing diode module, a driving module, an on-off control module and a power supply module;

the first end of the zener diode module is connected to the wiring of the second end of the driving module and the grid electrode of the external IGBT, and the second end of the zener diode module is connected with the first end of the on-off control module; the second end of the on-off control module is connected with the second end of the external controller, and the third end of the on-off control module is connected with the ground; the on-off control module is used for switching on or switching off the connection between the voltage-stabilizing diode module and the ground; the voltage stabilizing diode module is used for stabilizing the initial voltage of the driving signal to a first voltage when the second end of the voltage stabilizing diode module is grounded and the initial voltage of the driving signal is larger than the first voltage.

2. The IGBT driving circuit according to claim 1, wherein the zener diode module comprises: at least one zener diode;

the cathode of a first one of the at least one zener diode is connected to the connection between the second end of the driving module and the grid electrode of the external IGBT, the anode of the last one of the at least one zener diode is connected with the first end of the on-off control module, the cathode of each one of the at least one zener diode is connected with the anode of the previous one of the at least one zener diode, and the anode of each one of the at least one zener diode is connected with the cathode of the next one of the at least one zener diode.

3. The IGBT drive circuit according to claim 1, wherein the drive module comprises: the driving circuit comprises a first resistor, a driving chip and a waveform adjusting module;

4. The IGBT driving circuit according to claim 3, wherein the waveform adjusting module includes: the second resistor, the third resistor and the first diode;

5. The IGBT driving circuit according to claim 3, wherein the power supply module includes: the direct-current power supply, the first capacitor and the electrolytic capacitor;

the positive electrode of the electrolytic capacitor is respectively connected with the direct-current power supply and the power supply end of the driving chip, and the negative electrode of the electrolytic capacitor is respectively connected with the ground and the grounding end of the driving chip;

6. The IGBT driving circuit according to any one of claims 1 to 5, wherein the on-off control module includes: the first triode, the fourth resistor, the fifth resistor, the sixth resistor and the second capacitor;

the base electrode of the first triode is connected with the second end of the external controller through the fourth resistor, the collector electrode of the first triode is connected with the second end of the zener diode module through the fifth resistor, and the emitter electrode of the first triode is connected with the ground;

7. The IGBT driving circuit according to claim 6, further comprising: a protection module;

the first end of the protection module is connected with the first end of the voltage-stabilizing diode module and the grid electrode of the external IGBT respectively, and the second end of the protection module is connected with the emitter electrode of the external IGBT; the protection module is used for stabilizing the voltage between the grid electrode and the emitter electrode of the external IGBT to a second voltage.

8. The IGBT driving circuit according to claim 7, wherein the protection module includes: a first zener diode and a seventh resistor;

the anode of the first zener diode is connected with the emitter of the external IGBT, and the cathode of the zener diode is connected with the first end of the zener diode module and the grid of the external IGBT respectively;

the first end of the seventh resistor is connected with the positive electrode of the first zener diode, and the second end of the seventh resistor is connected with the negative electrode of the first zener diode.

9. An electromagnetic heating apparatus, comprising: the IGBT drive circuit, main circuit, controller, synchronous hardware circuit according to any one of claims 1 to 8;

10. The electromagnetic heating apparatus of claim 9, wherein the main circuit comprises: the device comprises an EMI filter circuit, a rectifier circuit, a filter capacitor, an LC resonant circuit and an IGBT;

the second end of the LC resonance circuit is connected with the collector of the IGBT, and the third end of the LC resonance circuit is connected with the first end of the synchronous hardware circuit; and the grid electrode of the IGBT is connected with the first end of the IGBT driving circuit.