Crosstalk suppression circuit and method with self-recovery function based on GaN HEMT

Abstract

The invention discloses a crosstalk suppression circuit and method with a self-recovery function based on a GaN HEMT, and belongs to the technical field of power electronics and power transmission, and the circuit topology structure comprises a square wave gating module, a resistor R1, a capacitor C1, a diode D1 and a diode D2. According to the method, the capacitor is charged in the gate opening process, then when the GaN HEMT is turned off and enters the dead time, the anode potential of the capacitor is changed into 0 and is clamped by the diode, and the capacitor provides negative voltage for the gate-source electrode of the GaN HEMT; when the positive crosstalk comes, the gate source voltage is a negative value, and the positive crosstalk can be successfully suppressed; and finally, the grid source voltage is recovered to 0 before the negative crosstalk comes, so that the negative crosstalk is prevented from being intensified. According to the invention, a simple passive device architecture is adopted, an additional power supply and control unit are not needed, the switching speed of the device is not influenced, additional power loss is not increased, the cost is low, the stability is high, positive and negative crosstalk can be effectively inhibited, and the operation reliability and conversion efficiency of a power conversion system can be remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of power electronics and electric transmission, and particularly relates to a crosstalk suppression circuit and method based on GaN HEMT with a self-recovery function. Background Art

[0002] Wide-bandgap power semiconductor devices, exemplified by gallium nitride high electron mobility transistors (GaN HEMTs), are attracting increasing attention in both the academic and industrial fields of power electronics due to their fast switching speeds and low conduction losses. These advantages enable GaN HEMTs to achieve higher efficiency and power density in applications such as data centers, electric vehicles, and aerospace propulsion systems. However, despite these advantages, GaN HEMTs suffer from a low threshold voltage, making them more sensitive to interfering signals. The combination of the high switching speed and low threshold voltage of GaN HEMTs makes them more susceptible to crosstalk.

[0003] In a half-bridge circuit, when the device is turned on or off, a high di / dt and dv / dt , which can generate positive and negative crosstalk voltage spikes on complementary devices. The positive crosstalk voltage may exceed the threshold voltage, causing the device to malfunction. The negative crosstalk voltage may exceed the negative withstand voltage of the device, causing negative breakdown and damage. Therefore, it is necessary to take measures to suppress the positive and negative crosstalk between devices.

[0004] Many methods and strategies for suppressing device crosstalk have been proposed, mainly including reducing the device dv / dt and di / dt , reduce gate loop impedance and use negative voltage drive, etc. Add additional capacitance at the gate-source or increase gate resistance to reduce the device's dv / dt and di / dt Crosstalk reduction is one of the primary measures to mitigate crosstalk. This relatively simple approach can suppress crosstalk to a certain extent, but it reduces switching speed and increases switching losses, hindering the high-frequency application advantages of GaN HEMTs. Some research has achieved crosstalk suppression by creating a low gate impedance path during the crosstalk generation phase. This approach has a minimal impact on switching speed, but requires additional control and complex design, adding cost and circuit complexity.

[0005] Negative voltage drive is also a common method for suppressing device crosstalk. It can effectively suppress positive crosstalk, but it also increases the risk of device breakdown caused by negative crosstalk. In addition, since GaN HEMTs do not have body diodes, negative voltage drive may increase the reverse conduction loss of the device. In addition, some methods require additional power supply and control, which will increase cost and circuit volume. The multi-level gate drive method suppresses the positive and negative crosstalk of the device by maintaining a constant negative voltage during positive crosstalk and returning to zero level during negative crosstalk. The method of maintaining a constant negative voltage during positive crosstalk interacts with the reverse conduction characteristics of GaN devices and may result in relatively large reverse conduction losses. In addition, an additional comparator circuit is required, which will increase the complexity of the design. Based on the above analysis, it can be concluded that existing crosstalk suppression research has problems such as complex driver design, limited suppression effect, or additional negative effects.

[0006] Today, GaN HEMT design and manufacturing technologies are rapidly developing, and there is an urgent need for their high-reliability and high-efficiency applications in converters. Therefore, research is crucial to achieve quantitative crosstalk suppression, reduce switching losses, and improve device reliability and efficiency while addressing actual operating conditions at minimal cost. Summary of the Invention

[0007] The purpose of the present invention is to address the above-mentioned deficiencies in the prior art and to provide a crosstalk suppression circuit and method based on GaN HEMT with self-recovery function, so as to solve the problems in existing crosstalk suppression research such as complex driver design, limited suppression effect or additional negative effects.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is: In the first aspect, a crosstalk suppression circuit with self-recovery function based on GaN HEMT includes a square wave gating module, a resistor R 1. Capacitor C 1. Diode D 1 and diode D 2; the capacitor C 1 and resistor R 1 After being connected in parallel with the diode D 1 anode and diode D 2 is connected to the anode; The square wave gating module includes a field effect transistor M 1 and field effect tube M 2; The field effect tube M 1 gate and field effect tube M 2's gate is grounded, the field effect tube M 1's drain and field effect transistor M 2 is connected to the drain of the drive resistor; the field effect tube M1. Source connection driver power supply V G , field effect transistor M 2 source connection capacitance C One end of 1, resistor R One end of 1, diode D 1 anode and diode D 2 anode; the capacitor C 1 and resistor R The other end of 1 is connected to the driving power supply V G ,diode D 1's cathode is grounded, and the diode D The cathode of 2 is connected to the gate pin of the GaN device.

[0009] Furthermore, field effect transistors M 1 is a PMOS field effect tube; field effect tube M 2 is an NMOS field effect transistor.

[0010] In a second aspect, a method for suppressing a crosstalk suppression circuit with a self-recovery function based on a GaN HEMT includes the following steps: S1. Quantify the margin of positive crosstalk voltage and negative crosstalk voltage of GaN devices. S2. Based on the margin quantification analysis results, the positive crosstalk voltage and negative crosstalk voltage of the GaN device are calculated using the crosstalk voltage estimation method. S3. Design the parameters of the electrical components in the crosstalk suppression circuit based on the suppression targets of the positive and negative crosstalk of the GaN device; S4, in the first stage of operation, the capacitor C 1. Charging during the gate-on phase of the GaN device; S5, in the second stage of operation, the capacitor C 1 acts as a negative voltage supply during the dead time and through a resistor R 1 discharge; S6. In the third stage of operation, the crosstalk suppression circuit provides a negative voltage, making the gate-source voltage of the GaN device negative, thereby suppressing the forward crosstalk voltage. S7. In the fourth stage of operation, the GaN gate-source voltage is restored to 0 through the negative voltage self-recovery function of the crosstalk suppression circuit.

[0011] Furthermore, in S1, a margin quantification analysis is performed on the positive crosstalk voltage and negative crosstalk voltage of the GaN device, including: the positive crosstalk voltage spike of the GaN device does not exceed the threshold voltage, and the negative crosstalk voltage spike does not exceed the maximum negative withstand voltage of the GaN device, specifically expressed as: Where, V P is the positive crosstalk voltage, V N is the negative crosstalk voltage, V th is the device threshold voltage, V ngs_max is the maximum negative withstand voltage of the device, V gs_off Turn off the drive voltage for the device.

[0012] Furthermore, in S2, the positive crosstalk voltage ∆ of the GaN device is calculated. V P and negative crosstalk voltage ∆ V N , respectively expressed as: Where, V in is the input voltage, C gs is the gate-source capacitance; C gd is the gate-drain capacitance; C iss is the input capacitance, indicating C gs and C gd sum; T r and T f are the rise and fall times of the drain-source voltage, respectively; R G is the driving resistor.

[0013] Furthermore, in S3, the suppression targets for positive and negative crosstalk of GaN devices include: the capacitor in the crosstalk suppression circuit C 1 and resistor R The value of 1 must satisfy the requirement that the time it takes for the negative voltage to recover to 0 is greater than the dead time and that the time it takes for the negative voltage to recover to 0 is less than 0.2 times the switching period. The suppression target is specifically expressed as: Where, R G_int is the internal parasitic gate resistance of the GaN device, Tdt is the dead time, T S is the switching cycle.

[0014] Furthermore, in S4, during the first stage of operation, the capacitor C 1. Charging is performed during the gate-on phase of the GaN device. The specific process is as follows: When the gate of the GaN device is turned on, the driving voltage is 6V and the field effect tube M 1 conduction, field effect tube M 2 Turn off; drive power through the gate resistor R G and gate inductance L G Gate-source capacitance C gs Charging, GaN device turns on; At the same time, the driving power supply to the capacitor C 1 Charging, capacitor C 1The voltage on the left is higher than the voltage on the right; due to the diode D 1 is turned on, and a positive conduction voltage drop occurs V F ,capacitance C 1 The voltage on the right side will be clamped at V F On, finally, the capacitor C The voltage across 1 is V G - V F .

[0015] Furthermore, in S5, during the second phase of operation, the capacitor C 1 acts as a negative voltage supply during the dead time and through a resistor R 1 discharge, the specific process is: At the beginning of the second stage, the driving voltage of the GaN device changes from high level to low level, and the field effect transistor M 1 turns off, and the GaN device turns off, and the complementary device Q 1 produces negative crosstalk; at this time, the capacitor C The voltage across 1 will become -( V G - V F ),diode D 1 is off, FET M 2 is on, capacitor C 1 acts as a negative voltage source to reduce the gate-source capacitance of the GaN device C gs Discharge to negative voltage; at this time, the capacitor C 1 will pass through the resistorR 1Discharge.

[0016] Furthermore, in S6, in the third stage of operation, the crosstalk suppression circuit provides a negative voltage, making the gate-source voltage of the GaN device negative, thereby suppressing the forward crosstalk voltage. The specific process is as follows: At the beginning of the third phase, the complementary devices Q 1 is turned on, due to transient commutation, high dv / dt and di / dt A positive crosstalk voltage spike will be generated on the bottom GaN device; at this time, the gate-source voltage of the GaN device v gs In the self-recovery process, it is negative, thereby suppressing the positive crosstalk voltage amplitude; and the diode D 1 has anode voltage lower than cathode voltage, so the diode D 1 is still in the off state; The gate-source voltage v gs During the self-recovery period, the diode D 2. Provide a path with lower impedance than the gate loop, thereby reducing the impedance of the current path and suppressing the positive crosstalk voltage amplitude; when positive crosstalk occurs, the GaN device remains off and the gate-source voltage v gs Restore to zero.

[0017] Furthermore, in S7, in the fourth stage of operation, the negative voltage self-recovery function of the crosstalk suppression circuit is used to restore the GaN gate-source voltage to 0. The specific process is as follows: At the beginning of the fourth phase, the complementary devices Q 1 is turned off, due to the bridge arm commutation, high dv / dt and di / dt A negative crosstalk voltage spike will be generated on the bottom GaN device; this negative crosstalk voltage spike is suppressed by the low impedance path; At the same time, the gate-source voltage of the GaN device v gs It has recovered to 0. This stage is in the second dead time stage. When the driving signal of the GaN device arrives, this stage ends and the crosstalk suppression circuit enters the next switching cycle.

[0018] The crosstalk suppression circuit and method with self-recovery function based on GaN HEMT provided by the present invention have the following beneficial effects: The method of the present invention is based on the positive and negative crosstalk voltage characteristics to establish a crosstalk suppression circuit. RCA quantitative design method for key network parameters is proposed, and specifications for the selection of key components are given. The present invention is widely used in bridge circuits, adopts a simple passive component architecture, does not require an additional power supply and control unit, does not affect the switching speed of the device, does not increase additional power loss, and can effectively suppress positive and negative crosstalk, thereby significantly improving the operating reliability and conversion efficiency of the power conversion system.

[0019] The method of the present invention first quantifies the peak positive and negative crosstalk of the GaN HEMT and calculates the positive and negative crosstalk voltages based on the crosstalk model. The specific selection of resistors and capacitors is then quantitatively calculated based on the theoretical crosstalk value, completing the quantitative design of key parameters of the crosstalk suppression circuit. The method is then applied to a half-bridge circuit. First, the capacitor charges during the gate-on process. Then, when the GaN HEMT is turned off and enters the dead time, the anode potential of the energy storage capacitor becomes zero and is clamped by the diode. The capacitor provides a negative voltage for the gate-source of the GaN HEMT. When positive crosstalk occurs, the gate-source voltage is negative, successfully suppressing the positive crosstalk. Finally, the gate-source voltage is restored to zero before the onset of negative crosstalk, preventing the aggravation of negative crosstalk. The present invention utilizes only a simple passive device architecture, eliminating the need for an additional power supply and control unit. It can quantitatively suppress crosstalk. Compared with existing methods, this method is low-cost and highly stable, significantly improving the reliability and efficiency of power conversion systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of a crosstalk suppression circuit according to embodiment 1 of the present invention, wherein Figure 1 (a) is a schematic diagram of a half-bridge circuit; Figure 1 (b) is for passive tube Q Specific circuit diagram of the crosstalk suppression circuit 2.

[0021] Figure 2 This is the RC network selection area for the suppression circuit in Example 2 of the present invention.

[0022] Figure 3 This is the first stage of the operation of the half-bridge circuit in which the crosstalk suppression circuit of Example 2 of the present invention is used.

[0023] Figure 4 This is the second stage of the crosstalk suppression circuit used in the second embodiment of the present invention for the operation of the half-bridge circuit.

[0024] Figure 5 This is the third stage of the crosstalk suppression circuit used in the second embodiment of the present invention for the half-bridge circuit.

[0025] Figure 6 This is the fourth stage of the crosstalk suppression circuit used in the second embodiment of the present invention for the operation of the half-bridge circuit.

[0026] Figure 7 This is the overall waveform of the process in which the crosstalk suppression circuit of Example 2 of the present invention is used in a half-bridge circuit.

[0027] Figure 8 This is the crosstalk suppression experiment waveform of Example 2 of the present invention, wherein: Figure 8 (a) is the crosstalk suppression test waveform under 100V / 10A working condition; Figure 8 (b) is the crosstalk suppression experimental waveform under 100V / 15A working conditions; Figure 8 (c) is the waveform of the crosstalk suppression experiment under 100V / 20A working condition; Figure 8 (d) in the figure is the crosstalk suppression experiment waveform under 100V / 25A working condition. DETAILED DESCRIPTION

[0028] The specific embodiments of the present invention are described below to facilitate understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the appended claims, these changes are obvious, and all inventions and creations utilizing the concepts of the present invention are protected.

[0029] Example 1 The crosstalk suppression circuit with self-recovery function based on GaN HEMT of this embodiment can be applied in bridge circuits. Figure 1 (a) in the circuit. This embodiment can effectively solve the problem of gate-source voltage overshoot caused by crosstalk during high-frequency switching, avoid device gate breakdown, and improve the reliability of the device in long-term operation. Figure 1 (b) in the above clauses shall specifically include: Square wave gating module, resistor R 1. Capacitor C 1. Diode D 1 and diode D 2. Capacitor C 1 and resistor R 1 After being connected in parallel with the diode D 1 anode and diode D 2 is connected to the anode; Specifically, the square wave gating module of this embodiment includes a field effect transistor M 1 and field effect tube M 2. Field-effect transistor M 1 gate and field effect tube M 2's gate is grounded, the field effect tube M 1's drain and field effect transistor M 2. Drain connected to the drive resistor R G Field-effect transistor M 1. Source connection driver power supply VG , field effect transistor M 2 source connection capacitance C One end of 1, resistor R One end of 1, diode D 1 anode and diode D 2 anode; capacitor C 1 and resistor R The other end of 1 is connected to the driving power supply V G ,diode D 1's cathode is grounded, and the diode D The cathode of 2 is connected to the gate pin of the GaN device.

[0030] The GaN HEMT of the present invention is referred to as a GaN device; As a preferred embodiment of this embodiment, the field effect tube M 1 is a PMOS field effect tube; field effect tube M 2 is an NMOS field effect transistor.

[0031] Example 2 This embodiment is based on the crosstalk suppression circuit in embodiment 1, and provides a crosstalk suppression method based on GaN HEMT with self-recovery function. Figure 1 、 Figure 3 、 Figure 4 、 Figure 5 in Q 2 is a GaN device. This embodiment specifically includes the following steps: S1. Quantify the margin of positive crosstalk voltage and negative crosstalk voltage of GaN devices. In this embodiment, to ensure safe operation of the GaN device and achieve good crosstalk suppression, a margin quantification analysis is performed on the positive and negative crosstalk voltages of the GaN device. It is required that the positive crosstalk voltage spike of the GaN device does not exceed the threshold voltage, and the negative crosstalk voltage spike does not exceed the maximum negative withstand voltage of the GaN device. To further ensure safe operation, a margin of 1.5 times should be reserved. Based on the above requirements, the margin quantification analysis is specifically expressed as follows: Where, V P is the positive crosstalk voltage, V N is the negative crosstalk voltage, V th is the device threshold voltage, Vngs_max is the maximum negative withstand voltage of the device, V gs_off Turn off the drive voltage for the device.

[0032] S2. Based on the margin quantification analysis results, the positive crosstalk voltage and negative crosstalk voltage of the GaN device are calculated using the crosstalk voltage estimation method. This embodiment builds a crosstalk calculation model to calculate the positive crosstalk voltage ∆ V P and negative crosstalk voltage ∆ V N , which is specifically expressed as: Where, V in is the input voltage, C gs is the gate-source capacitance; C gd is the gate-drain capacitance; C iss is the input capacitance, indicating C gs and C gd sum; T r and T f are the rise and fall times of the drain-source voltage, respectively; R G is the gate resistance.

[0033] S3. Design the parameters of the electrical components in the crosstalk suppression circuit based on the suppression targets of the positive and negative crosstalk of the GaN device; refer to Figure 2 In order to better suppress the crosstalk voltage, this embodiment must ensure that the passive tube Q 2 After shutting down and in the active tube (complementary device) Q1 A sufficient negative voltage needs to be generated before it is turned on. Therefore, the values ​​of the resistors and capacitors in the crosstalk suppression circuit need to ensure that the time for the negative voltage to recover to 0 is greater than the dead time. In addition, since GaN devices do not have a reverse body diode, there is no reverse recovery process. However, due to its own reverse conduction characteristics, GaN devices can still conduct in the reverse direction, but the reverse conduction voltage drop during its dead time is usually large, which will result in a large dead time loss. Therefore, in order to effectively reduce reverse conduction losses and reduce the possibility of reverse breakdown of the device, when a negative crosstalk voltage is generated, the gate-source voltage of the GaN device should be restored to zero as quickly as possible. Therefore, the values ​​of the resistors and capacitors in the crosstalk suppression circuit need to ensure that the time for the negative voltage to recover to 0 is less than about 0.2 times the switching period. Based on this, the suppression target of this embodiment is specifically expressed as: Where, R G_int is the internal parasitic gate resistance of the GaN device, T dt is the dead time, T S is the switching cycle; In this embodiment, based on the relationship that needs to be met for the suppression target, the resistors and capacitors can be selected quantitatively. In addition, the other device models of this embodiment are preferably: the diode is RF202LAM2S, and the square wave gating module is Si553CDL.

[0034] S4, in the first stage of operation, the capacitor C 1. Charging during the gate-on phase of the GaN device; In this embodiment, after completing the selection of parameters of electrical components in the crosstalk suppression circuit in step S3, the entire crosstalk suppression circuit is applied to a half-bridge circuit; refer to Figure 3 , in the first stage of the half-bridge circuit operation [ t 0- t 1], the specific process of this stage is: The driving voltage of the GaN device is 6V. At this time, the field effect tube M 1 conduction, field effect tube M 2 is turned off. During this period, the driving power is supplied through the driving resistor R G and gate inductance L G Gate-source capacitance C gs Charging, GaN device turns on.

[0035] In addition, the drive power will also C1 charge, which will make the capacitor C 1The voltage on the left side is higher than on the right side. D 1 is conducting, and there will be a positive conduction voltage drop V F , so the capacitor C 1 The voltage on the right side will be clamped quickly at V F Finally, the capacitor C The voltage across 1 is V G - V F ,in V G Since no commutation occurs during this phase, no crosstalk occurs.

[0036] S5, in the second stage of operation, the capacitor C 1 acts as a negative voltage supply during the dead time and through a resistor R 1 discharge; refer to Figure 4 , in the second stage of the half-bridge circuit operation [ t 1- t 2], the specific process of this stage is as follows: This stage is the dead time. t 1 moment, GaN devices ( Q 2) The driving voltage changes from high level to low level, the field effect tube M 1 is off, so the GaN device is off, which will cause the complementary device Q 1 produces negative crosstalk. At this time, the capacitor C The voltage across 1 will become -( V G - V F ). Accordingly, the diode D 1 is off, FET M 2 is on, capacitor C 1 acts as a negative voltage source to reduce the gate-source capacitance of the GaN device C gs Rapidly discharge to negative voltage. At this time, the capacitor C 1 will pass R 1 discharge, RC The time constant determines the time it takes for the negative pressure to recover.

[0037] S6. In the third stage of operation, the crosstalk suppression circuit provides a negative voltage, making the gate-source voltage of the GaN device negative, thereby suppressing the forward crosstalk voltage. refer to Figure 5 , in the third stage of the half-bridge circuit operation [ t 2- t3], the specific process of this stage is: exist t 2 moments, complementary devices Q 1 is turned on, due to transient commutation, high dv / dt and di / dt A positive crosstalk spike will be generated on the bottom GaN device. At this time, the gate-source voltage of the GaN device v gs Still in the self-recovery process, it is negative, which will effectively suppress the positive crosstalk voltage amplitude. D 1's anode voltage is lower than its cathode voltage, so D 1 is still in the off state. v gs During the self-recovery period, the diode D 2 provides a path with lower impedance than the gate loop, thereby reducing the impedance of the current path and suppressing the crosstalk amplitude. After crosstalk occurs, the GaN device remains off and the gate-source voltage v gs Restore to zero.

[0038] S7. In the fourth stage of operation, the GaN gate-source voltage is restored to 0 through the negative voltage self-recovery function of the crosstalk suppression circuit.

[0039] refer to Figure 6 , in the fourth stage of the half-bridge circuit operation [ t 3- t 4], the specific process of this stage is: exist t 3 moments, complementary devices Q 1 is turned off. Similarly, due to the bridge arm commutation, the high dv / dt and di / dt A negative crosstalk spike will be generated on the bottom GaN device, but this crosstalk can still pass through a low-impedance path, thus suppressing the crosstalk amplitude to a certain extent.

[0040] At the same time, the gate-source voltage of the GaN device v gs The self-recovery circuit does not aggravate the negative crosstalk spike's impact on the device. This mode is also in the second dead time phase, which ends when the driving signal of the GaN device arrives, and the entire circuit enters the next switching cycle.

[0041] Figure 7 It is the key waveform of the gate-source voltage in the entire switching process. Based on the present invention, the positive and negative crosstalk is accurately suppressed.

[0042] like Figure 8 As shown in the figure, the test was carried out at four loads of 10A, 15A, 20A and 25A at a bus voltage of 100V. Figure 8 (a) in the figure shows that under the 100V / 10A operating condition, the positive crosstalk of the GaN HEMT can be reduced from 2.110V to 0.625V, a reduction of about 70%, and the negative crosstalk is 6.216V. The negative crosstalk of the traditional circuit is 5.971V, which does not have a significant impact on the negative crosstalk.

[0043] like Figure 8 In (b), under the 100V / 15A working condition, the positive crosstalk is reduced from 2.031V to 0.646V, and the negative crosstalk is 6.855V, while the negative crosstalk of the traditional circuit is 7.145V, which does not have a significant impact on the negative crosstalk.

[0044] like Figure 8 In (c), under the 100V / 20A operating condition, the positive crosstalk is reduced from 1.946V to 0.665V.

[0045] like Figure 8 In (d), under the operating conditions of 100V / 25A, the positive crosstalk is reduced from 2.075V to 0.660V. Experimental verification shows that the present invention can effectively reduce positive crosstalk and prevent the device from mis-conducting, and the impact of the present invention on negative crosstalk is negligible.

[0046] Although the specific embodiments of the invention are described in detail in conjunction with the accompanying drawings, this should not be construed as limiting the scope of protection of this patent. Within the scope described by the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of this patent.

Claims

1. A crosstalk suppression circuit with self-recovery function based on GaN HEMT, characterized in that: Including square wave gating module, resistor R 1. Capacitor C 1. Diode D 1 and diode D 2; the capacitor C 1 and resistor R 1 After being connected in parallel with the diode D 1 anode and diode D 2 is connected to the anode; The square wave gating module includes a field effect transistor M 1 and field effect tube M 2; The field effect tube M 1 gate and field effect tube M 2's gate is grounded, the field effect tube M 1's drain and field effect transistor M 2 is connected to the drain of the drive resistor; the field effect tube M 1. Source connection driver power supply V G , field effect transistor M 2 source connection capacitance C One end of 1, resistor R One end of 1, diode D 1 anode and diode D 2 anode; the capacitor C 1 and resistor R The other end of 1 is connected to the driving power supply V G ,diode D 1's cathode is grounded, and the diode D The cathode of 2 is connected to the gate pin of the GaN device.

2. The crosstalk suppression circuit with self-recovery function based on GaN HEMT according to claim 1, characterized in that: The field effect tube M 1 is a PMOS field effect tube; field effect tube M 2 is an NMOS field effect transistor.

3. A method for suppressing crosstalk in a GaN HEMT-based self-recovery circuit according to claim 1 or 2, characterized in that: The following steps are involved: S1. Quantify the margin of positive crosstalk voltage and negative crosstalk voltage of GaN devices. S2. Based on the margin quantification analysis results, the positive crosstalk voltage and negative crosstalk voltage of the GaN device are calculated using the crosstalk voltage estimation method. S3. Design the parameters of the electrical components in the crosstalk suppression circuit based on the suppression targets of the positive and negative crosstalk of the GaN device; S4, in the first stage of operation, the capacitor C 1. Charging during the gate-on phase of the GaN device; S5, in the second stage of operation, the capacitor C 1 acts as a negative voltage supply during the dead time and through a resistor R 1 discharge; S6. In the third stage of operation, the crosstalk suppression circuit provides a negative voltage, making the gate-source voltage of the GaN device negative, thereby suppressing the forward crosstalk voltage. S7. In the fourth stage of operation, the GaN gate-source voltage is restored to 0 through the negative voltage self-recovery function of the crosstalk suppression circuit.

4. The method for suppressing crosstalk suppression circuit with self-recovery function based on GaN HEMT according to claim 3, characterized in that: In S1, a margin quantification analysis is performed on the positive crosstalk voltage and negative crosstalk voltage of the GaN device, including: the positive crosstalk voltage spike of the GaN device does not exceed the threshold voltage, and the negative crosstalk voltage spike does not exceed the maximum negative withstand voltage of the GaN device, specifically expressed as: Where, V P is the positive crosstalk voltage, V N is the negative crosstalk voltage, V th is the device threshold voltage, V ngs_max is the maximum negative withstand voltage of the device, V gs_off Turn off the drive voltage for the device.

5. The crosstalk suppression method according to claim 3, wherein: In S2, the positive crosstalk voltage ∆ of the GaN device is calculated respectively. V P and negative crosstalk voltage ∆ V N , respectively expressed as: Where, V in is the input voltage, C gs is the gate-source capacitance; C gd is the gate-drain capacitance; C iss is the input capacitance, indicating C gs and C gd sum; T r and T f are the rise and fall times of the drain-source voltage, respectively; R G is the driving resistor.

6. The method for suppressing crosstalk suppression circuit with self-recovery function based on GaN HEMT according to claim 5, characterized in that: In S3, the suppression targets for positive and negative crosstalk of GaN devices include: the capacitors in the crosstalk suppression circuit C 1 and resistor R The value of 1 must satisfy the requirement that the time it takes for the negative voltage to recover to 0 is greater than the dead time and the time it takes for the negative voltage to recover to 0 is less than 0.2 times the switching period. The suppression target is specifically expressed as: Where, R G_int is the internal parasitic gate resistance of the GaN device, T dt is the dead time, T S is the switching cycle.

7. The crosstalk suppression method of the GaN HEMT-based self-recovery circuit according to claim 3, wherein: In S4, during the first stage of operation, the capacitor C 1. Charging is performed during the gate-on phase of the GaN device. The specific process is as follows: When the gate of the GaN device is turned on, the driving voltage is 6V and the field effect tube M 1 conduction, field effect tube M 2. Shut down; The driving power is passed through the driving resistor R G and gate inductance L G Gate-source capacitance C gs Charging, GaN device turns on; At the same time, the driving power supply to the capacitor C 1 Charging, capacitor C 1The voltage on the left is higher than the voltage on the right; due to the diode D 1 is turned on, and a positive conduction voltage drop occurs V F ,capacitance C 1 The voltage on the right side will be clamped at V F On, finally, the capacitor C The voltage across 1 is V G - V F .

8. The crosstalk suppression method of the GaN HEMT-based self-recovery circuit according to claim 3, wherein: In the S5, in the second stage of operation, the capacitor C 1 acts as a negative voltage supply during the dead time and through a resistor R 1 discharge, the specific process is: At the beginning of the second stage, the driving voltage of the GaN device changes from high level to low level, and the field effect transistor M 1 turns off, and the GaN device turns off, and the complementary device Q 1 produces negative crosstalk; at this time, the capacitor C The voltage across 1 will become -( V G - V F ),diode D 1 is off, FET M 2 is connected, capacitor C 1 acts as a negative voltage source to reduce the gate-source capacitance of the GaN device C gs Discharge to negative voltage; at this time, the capacitor C 1 will pass through the resistor R 1Discharge.

9. The crosstalk suppression method of the GaN HEMT-based self-recovery circuit according to claim 3, wherein: In the third stage of operation in S6, the crosstalk suppression circuit provides a negative voltage, so that the gate-source voltage of the GaN device is negative, thereby suppressing the forward crosstalk voltage. The specific process is as follows: At the beginning of the third phase, the complementary devices Q 1 is turned on, due to transient commutation, high dv / dt and di / dt A positive crosstalk voltage spike will be generated on the bottom GaN device; at this time, the gate-source voltage of the GaN device v gs In the self-recovery process, it is negative, thereby suppressing the positive crosstalk voltage amplitude; and the diode D 1 has anode voltage lower than cathode voltage, so the diode D 1 is still in the off state; The gate-source voltage v gs During the self-recovery period, the diode D 2. Provide a path with lower impedance than the gate loop, thereby reducing the impedance of the current path and suppressing the positive crosstalk voltage amplitude; when positive crosstalk occurs, the GaN device remains off and the gate-source voltage v gs Restore to zero.

10. The crosstalk suppression method of the GaN HEMT-based self-recovery circuit according to claim 3, wherein: In the fourth stage of operation in S7, the negative voltage self-recovery function of the crosstalk suppression circuit is used to restore the GaN gate-source voltage to 0. The specific process is as follows: At the beginning of the fourth phase, the complementary devices Q 1 is turned off, due to the bridge arm commutation, high dv / dt and di / dt A negative crosstalk voltage spike will be generated on the bottom GaN device; This negative crosstalk voltage spike is suppressed through the low impedance path; At the same time, the gate-source voltage of the GaN device v gs It has recovered to 0. This stage is in the second dead time stage. When the driving signal of the GaN device arrives, this stage ends and the crosstalk suppression circuit enters the next switching cycle.

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