CN-122026876-A - Driving circuit of semiconductor power switch device

CN122026876ACN 122026876 ACN122026876 ACN 122026876ACN-122026876-A

Abstract

The invention relates to the technical field of power electronic devices, in particular to a driving circuit of a semiconductor power switching device, which comprises a driving module connected with a grid electrode of the semiconductor power switching device and used for responding to a driving signal to turn on or turn off the semiconductor power switching device, a filtering limiting module respectively connected with a power source electrode of the semiconductor power switching device and a clamping module and used for detecting the common source inductance voltage of the semiconductor power switching device and transmitting the common source inductance voltage to the clamping module, wherein the clamping module is used for reducing the grid source voltage of the semiconductor power switching device to a first voltage when the common source inductance voltage reaches a preset voltage threshold value, and the drain current of a saturation region of the semiconductor power switching device is larger than a load current when the grid source voltage of the semiconductor power switching device is reduced to the first voltage.

Inventors

CHENG XU
NIU YUKUN
LI ZHENCONG
PEI XINGYU
LI JIANBIAO
WU HONGYUAN
ZHAO XIAOYAN
ZHENG YUZE
CHEN YONG
ZHANG FAN
LIAO YANQUN
SONG XUHUI
GAO ZHIHUA
ZHANG XIAOLU
HE JIANZONG

Assignees

广东电网有限责任公司珠海供电局

Dates

Publication Date: 20260512
Application Date: 20260129

Claims (10)

1. A drive circuit of a semiconductor power switching device, comprising: The driving module is connected with the grid electrode of the semiconductor power switching device and is used for responding to a driving signal to turn on or off the semiconductor power switching device; The filtering amplitude limiting module is respectively connected with the power source of the semiconductor power switching device and the clamping module, and is used for detecting the common-source inductance voltage of the semiconductor power switching device and transmitting the common-source inductance voltage to the clamping module; The clamping module is connected with the grid electrode of the semiconductor power switching device and is used for reducing the grid electrode and source electrode voltage of the semiconductor power switching device to a first voltage when the common source inductance voltage reaches a preset voltage threshold value so as to inhibit the change rate of drain electrode current, and when the grid electrode and source electrode voltage of the semiconductor power switching device is reduced to the first voltage, the drain electrode current of a saturation region of the semiconductor power switching device is larger than the load current.
2. The driving circuit according to claim 1, wherein the clamp module includes a clamp driving unit and a clamp action unit; The clamping action unit is connected with the grid electrode of the semiconductor power switch device; The clamping driving unit is connected with the filtering amplitude limiting module and the clamping action unit and is used for switching on a loop formed by the clamping action unit and the grid electrode of the semiconductor power switch device when the common source inductance voltage reaches a preset voltage threshold value, so that the grid-source voltage of the semiconductor power switch device is reduced to a first voltage.
3. The driving circuit according to claim 2, wherein the clamp driving unit includes a first switching device, a first resistor, and a second resistor; One end of the first resistor is connected with the filtering amplitude limiting module, and the other end of the first resistor is connected with the first end of the first switching device and is used for conducting the first switching device when the common-source inductance voltage reaches a preset voltage threshold value; The second end of the first switching device is connected with one end of the second resistor and the first end of the clamping action unit respectively; The other end of the second resistor is connected with a first power supply and the second end of the clamping action unit respectively; when the first switching device is conducted, a loop formed by the clamping action unit and the grid electrode of the semiconductor power switching device is in a conducting state.
4. The driving circuit according to claim 3, wherein the clamp action unit comprises a second switching device and a voltage stabilizing element; the first end of the second switching device is connected with the second end of the first switching device; the second end of the second switching device is connected with the other end of the second resistor; The third end of the second switching device is connected with the voltage stabilizing element in series, and the voltage stabilizing element is connected with the grid electrode of the semiconductor power switching device; Wherein when the first switching device is turned on, the second switching device is turned on.
5. The driving circuit according to claim 4, wherein the driving module comprises a push-pull unit, wherein an input end of the push-pull unit is used for receiving a driving signal; The output end of the push-pull unit is connected with the on driving resistor and the off driving resistor respectively; the turn-on driving resistor is connected with a turn-on diode, and the turn-on diode is connected to the grid electrode of the semiconductor power switching device; the turn-off driving resistor is connected with a turn-off diode, and the turn-off diode is connected to the grid electrode of the semiconductor power switch device.
6. The drive circuit according to claim 5, further comprising an overcurrent protection unit and a control unit; The input end of the overcurrent protection unit is respectively connected with a Kelvin source electrode of the semiconductor power switch device and a power source electrode of the semiconductor power switch device, and is used for detecting a common source inductance voltage of the power source electrode of the semiconductor power switch device and converting the common source inductance voltage into drain current; The control unit is connected with the overcurrent protection unit and the push-pull unit and is used for judging whether the drain current is larger than a preset protection threshold value, and if yes, a locking signal is output to enable the push-pull unit to stop driving the semiconductor power switch device.
7. The driving circuit according to claim 6, wherein the overcurrent protection unit includes a third resistor, a fourth resistor, a first capacitor, a second capacitor, and an operational amplifier; One end of the third resistor is connected with the Kelvin source electrode of the semiconductor power switch device, and the other end of the third resistor is respectively connected with the negative input end of the operational amplifier and one end of the first capacitor; One end of the fourth resistor is connected with the power source electrode of the semiconductor power switching device, the other end of the fourth resistor is respectively connected with the positive input end of the operational amplifier and one end of the second capacitor, and the other end of the second capacitor is connected with the Kelvin source electrode of the semiconductor power switching device.
8. The driving circuit according to claim 7, wherein the filtering clipping module comprises a filtering unit and a clipping unit; the input end of the filtering unit is used for being connected with a power source electrode of the semiconductor power switching device; The input end of the filtering unit is connected with the input end of the amplitude limiting unit and is used for filtering interference signals in the common-source inductance voltage signals; the output end of the amplitude limiting unit is connected with the clamping module and used for limiting the amplitude of the common-source inductance voltage signal after filtering within a preset voltage range.
9. The driving circuit according to claim 8, wherein the push-pull unit comprises a half-bridge circuit including a third switching device and a fourth switching device; The first end of the third switching device is connected with the first end of the fourth switching device and is used as an input end of the push-pull unit; the second end of the third switching device is connected with a second power supply; the second end of the fourth switching device is connected with the first power supply; the third terminal of the third switching device is connected with the third terminal of the fourth switching device and serves as an output terminal of the push-pull unit.
10. The drive circuit of claim 9, wherein the clipping unit comprises a first clipping element and a second clipping element, the first clipping element and the second clipping element being connected in series.

Description

Driving circuit of semiconductor power switch device Technical Field The invention relates to the technical field of power electronic devices, in particular to a driving circuit of a semiconductor power switching device. Background The third generation semiconductor power switch device such as the SiC device has the advantages of high voltage resistance, high temperature resistance, high frequency and low loss, and compared with the Si IGBT, the on-resistance of the SiC device is smaller and almost no tailing current exists, so that the power electronic equipment can be pushed to be improved in the high-efficiency, light-weight and high-reliability directions. Specifically, the SiC device can adopt higher switching frequency, and the requirements on energy storage elements such as a filter, an inductor, a capacitor and the like are greatly reduced, so that the size of the device is reduced, and the power density is improved. However, the gate voltage for maintaining the SiC device on is relatively high, typically 15V to 20V, and in order to ensure reliable turn-off of the device, a negative voltage is typically applied to the gate to turn off, typically about-3V to-5V, and the PWM signal level output by the digital microcontroller is typically 0 to 5V, so that the conversion of the signal level and the amplification of the current need to be performed by using the gate driving circuit. For a SiC MOSFET in the practical application of a SiC device, because parasitic inductance exists in a conductor connected in a gate driving circuit, and parasitic parameters inside the device package are not negligible under the conditions of high drain current change rate di/dt and drain-source voltage change rate dv/dt generated by switching transient, the parasitic inductance and parasitic capacitance inside the SiC MOSFET form an oscillation loop, current and voltage oscillation can be generated when the SiC MOSFET is turned on and turned off, and the amplitude of the oscillation is influenced by the drain current change rate di/dt and the drain-source voltage change rate dv/dt generated by the turning on and turned off. For the traditional grid driving circuit, the smaller the driving resistance is, the faster the switching speed is, the switching transient time is shortened, the switching loss is reduced, meanwhile, serious voltage current oscillation is caused, in the switching-on process, the high drain current change rate di/dt generated by the high switching speed also causes serious reverse recovery current peak, extra current stress is caused, and especially for the SiC MOSFET configured in a half bridge, the drain current change rate di/dt in the switching-on process of a lower tube also causes voltage oscillation in the upper tube, and extra overvoltage damage risk is caused. And when the SiC MOSFET has short circuit faults, such as hard switch faults and load short circuit faults, the grid driving circuit is required to timely detect the occurrence of the short circuit and respond to the short circuit to timely turn off the MOSFET, so that the damage of devices caused by accumulation of a large amount of heat generated by excessive short circuit current on the SiC chip is prevented. However, the existing driving scheme has difficulty in reducing current oscillation while increasing the switching speed, and in suppressing short-circuit current. Disclosure of Invention The invention provides a driving circuit of a semiconductor power switch device, which is used for solving the technical problems that the current oscillation is difficult to reduce while the switching speed is improved and the short-circuit current is difficult to restrain in the existing driving scheme. In one aspect, the present invention provides a driving circuit of a semiconductor power switching device, comprising: The driving module is connected with the grid electrode of the semiconductor power switching device and is used for responding to a driving signal to turn on or off the semiconductor power switching device; The filtering amplitude limiting module is respectively connected with the power source of the semiconductor power switching device and the clamping module, and is used for detecting the common-source inductance voltage of the semiconductor power switching device and transmitting the common-source inductance voltage to the clamping module; The clamping module is connected with the grid electrode of the semiconductor power switching device and is used for reducing the grid electrode and source electrode voltage of the semiconductor power switching device to a first voltage when the common source inductance voltage reaches a preset voltage threshold value so as to inhibit the change rate of drain electrode current, and when the grid electrode and source electrode voltage of the semiconductor power switching device is reduced to the first voltage, the drain electrode current of a saturation region of the semiconductor power swit