IGBT module protection system for new energy commercial vehicle

Abstract

The invention discloses an IGBT module protection system for a new energy commercial vehicle. The IGBT module protection system comprises an IGBT module, a PWM driving interlocking module, a driving overvoltage and undervoltage protection module, an overcurrent protection module, a short-circuit protection module and an over-temperature overload protection module. The IGBT module protection system detects the current and temperature of the IGBT module through software to carry out overcurrent, overload and over-temperature protection so as to deal with damage caused by long-time heat accumulation of the IGBT module, and hardware integrates PWM interlocking, driving VGE overvoltage and undervoltage, output overcurrent and VCE desaturation detection to deal with damage caused by excessive instantaneous loss.

Description

Technical Field

[0001] The invention belongs to the technical field of IGBT module protection systems and relates to an IGBT module protection system for new energy commercial vehicles. Background Art

[0002] IGBT module is the core component of new energy controller. Once the IGBT module is damaged, the vehicle will be unable to drive. For safety reasons, it is very necessary to monitor its working status and provide corresponding protection for abnormal conditions. IGBT module damage is mostly caused by excessive junction temperature inside the IGBT chip. Excessive junction temperature is a process of heat accumulation, which is divided into short-term and long-term accumulation. Short-term conditions are usually short-circuit conditions, generally 10us five times the rated current, overcurrent 1ms twice the rated current, and long-term conditions are overload conditions. Summary of the invention

[0003] In order to solve the problems existing in the background technology, the present invention proposes an IGBT module protection system for new energy commercial vehicles. Taking IGBT module protection as a systematic strategy on new energy commercial vehicles, IGBT status monitoring and abnormal status protection can greatly reduce the risk of IGBT module damage.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is as follows: A new energy commercial vehicle IGBT module protection system, including: IGBT module, PWM drive interlock module, drive over-voltage and under-voltage protection module, overcurrent protection module, short circuit protection module, over-temperature and overload protection module; The first end of the PWM drive interlock module is connected to the second end of the over-temperature and overload protection module, the second end of the PWM drive interlock module is connected to the first end of the drive over- and under-voltage protection module, the third end of the PWM drive interlock module is connected to the second end of the overcurrent protection module, the first end of the IGBT module is connected to the second end of the drive over- and under-voltage protection module and the second end of the short-circuit protection module, the second end of the IGBT module is connected to the first end of the over-temperature and overload protection module, and the third end of the IGBT module is connected to the first end of the overcurrent protection module and the first end of the short-circuit protection module.

[0005] Furthermore, the driving over-voltage and under-voltage protection module includes a driving over-voltage and under-voltage protection circuit and an IGBT driving module, and the driving over-voltage and under-voltage protection circuit is connected to a first end of the IGBT driving module; The PWM drive interlocking module is a DSP module, and a first end of the DSP module is connected to a second end of the IGBT drive module; The overcurrent protection module includes a Hall current sampling module and a hardware overcurrent comparison module; The first end of the Hall current sampling module is connected to the third end of the IGBT module, the second end of the Hall current sampling module is connected to the second end of the hardware overcurrent comparison module, and one end of the hardware overcurrent comparison module is connected to the second end of the DSP module; The short-circuit protection module includes a short-circuit circuit, a first end of the short-circuit circuit is connected to a first end of the IGBT module and a third end of the IGBT driving module, and a second end of the short-circuit circuit is connected to a third end of the IGBT module and a first end of the Hall current sampling module; The over-temperature overload protection module includes an IGBT temperature sampling module, the IGBT module includes a thermistor NTC, a first end of the IGBT temperature sampling module is connected to the second end of the IGBT module, and a second end of the IGBT temperature sampling module is connected to the third end of the DSP module.

[0006] Furthermore, the IGBT module includes a thermistor NTC.

[0007] Furthermore, the DSP module includes a PWM output port and Output port, the IGBT driver module includes a first driver and a second driver, and the first driver and the second driver each include an IP port, an IN port, and an output port; The PWM output port is connected to the IP port of the first driver and the IN port of the second driver. The output port is connected to the IN port of the first driver and the IP port of the second driver; The PWM output port outputs a PWM signal, Output port output signal, PWM signal and The signal is a pair of complementary signals with dead zone. When the signal is interfered, PWM signal and When the signals are both at high level, the outputs of the upper and lower bridge arms of the IGBT module enter interlocking mode.

[0008] Further, the hardware overcurrent comparison module includes a fourth comparator COMP3 and a Vref port; The second end of the Hall current sampling module is connected to the inverting input end of the fourth comparator COMP3, the non-inverting input end of the fourth comparator COMP3 is connected to the Vref port, and the output end of the fourth comparator COMP3 is connected to the TZ6 pin of the DSP module; The output current of the IGBT module passes through the Hall current sampling module, converting the current signal into a voltage signal. The voltage signal is compared with the reference voltage Vref of the fourth comparator COMP3. When the reference voltage Vref threshold is exceeded, the fourth comparator COMP3 is reversed, and the DSP module uploads the hardware overcurrent fault, and at the same time shuts down the drive PWM signal and Signal; A current safety threshold will be pre-set in the DSP module as a supplement to the hardware overcurrent comparison protection module failure. The hardware overcurrent comparison protection module detects the overcurrent signal as a spike type. After the current collection in the overcurrent signal is filtered, the DSP module reacts more slowly to the spike-type overcurrent signal. When the hardware overcurrent protection fails, protection is provided by pre-setting the current safety threshold in the DSP module.

[0009] Further, the driving over-voltage and under-voltage protection circuit includes a diode D2, a diode D3, a diode D4, a resistor R1, a resistor R2, a resistor R3, a transistor Q2, a transistor Q3, a first comparator AMP1, a second comparator COMP1, a third comparator COMP2, a Vref1 port, and a Vref2 port; The non-inverting input terminal of the first comparator AMP1 is connected to the collector of the transistor Q2 and the cathode of the diode D4, the base of the transistor Q2 is connected to the base of the transistor Q3, the emitter of the transistor Q2 is connected to the collector of the transistor Q3 and one end of the resistor R1, the other end of the resistor R1 is connected to the anode of the diode D4, the cathode of the diode D2, and the IGBT driving module, the anode of the diode D2 is connected to the anode of the diode D3, the cathode of the diode D3 is connected to the inverting input terminal of the first comparator AMP1, the emitter of the transistor Q3, and the pin U_L_E of the IGBT module, and the resistor R1 is connected to the anode of the diode D4, the cathode of the diode D2, and the IGBT driving module. One end of the resistor R2 is connected to a 5V power supply and a resistor R3, the other end of the resistor R2 is connected to a TZ3 pin of the DSP module and an output end of the third comparator COMP2, the other end of the resistor R3 is connected to a TZ4 pin of the DSP module and an output end of the second comparator COMP1, an inverting input end of the second comparator COMP1 is connected to a Vref1 port, a non-inverting input end of the second comparator COMP1 is connected to an output end of the first comparator AMP1 and an inverting input end of the third comparator COMP2, and a non-inverting input end of the third comparator COMP2 is connected to a Vref2 port; When the voltage of the collector of the transistor Q2 is lower than the reference voltage Vref1, the second comparator COMP1 will reverse, and when the voltage of the collector of the transistor Q2 is higher than the reference voltage Vref2, the third comparator COMP2 will reverse. The second comparator COMP1 and the third comparator COMP2 are push-pull outputs. The TZ4 pin of the DSP module transmits a drive undervoltage lockout fault signal, and the TZ3 pin of the DSP module transmits a drive overvoltage lockout fault signal. When the DSP module receives a drive undervoltage lockout fault signal or transmits a drive overvoltage lockout fault signal, it immediately turns off the drive PWM signal and Signal, and upload driver over-voltage or under-voltage lockout fault.

[0010] Further, the short circuit protection circuit includes: a resistor R4, a diode D1, a diode D5, a transistor Q4, a capacitor C1, a Vref3 port, a fifth comparator COMP4, a VCE desaturation port, and a TIs port; The cathode of the diode D4 is connected to the non-inverting input terminal of the fifth comparator COMP4, the drain of the transistor Q4, the input terminal of the capacitor C1, and the input terminal of the resistor R4, the inverting input terminal of the fifth comparator COMP4 is connected to the Vref3 port, the output terminal of the fifth comparator COMP4 is connected to the VCE desaturation port, the gate of the transistor Q4 is connected to the cathode of the diode D5, the TIs port is connected to the anode of the diode D5 and the IGBT driving module, the source of the transistor Q4 is connected to the output terminal of the capacitor C1 and the U_L_E pin of the IGBT module, the output terminal of the resistor R1 is connected to the anode of the diode D1, and the cathode of the diode D1 is connected to the U_L_C pin of the IGBT module; When a short circuit occurs, the voltage across the IGBT module rises, and the voltage at the in-phase input of the fifth comparator COMP4 also rises. When the voltage at the in-phase input of the fifth comparator COMP4 is higher than the reference voltage Vref3, the fifth comparator COMP4 is triggered to output a Vce desaturation signal. After the DSP module detects the Vce desaturation signal, it turns off the drive PWM signal and signal, while uploading a short circuit fault.

[0011] Further, the IGBT temperature sampling module is connected to the thermistor NTC; The IGBT temperature sampling module converts the change in the resistance of the thermistor NTC into a voltage signal, collects the temperature of the IGBT module through the DSP module, and estimates the temperature of the IGBT module chip and diode through the junction temperature using the thermal impedance model. The junction temperature calculation formula of the thermal impedance model is: ,in is the total loss of the IGBT module, is the thermal resistance from junction temperature to case temperature, and TC is the case temperature. When the estimated junction temperature exceeds the IGBT module junction temperature derating value, an over-temperature fault will be triggered, limiting power or shutting down; As a supplement to the over-temperature protection, the IGBT module overload protection limits the power of the IGBT through the DSP module to further protect the operating junction temperature of the IGBT module from being lower than the maximum junction temperature derating value.

[0012] Compared with the prior art, the present invention has the following beneficial effects: The IGBT module protection system detects the current and temperature of the IGBT module through software to perform overcurrent, overload and overtemperature protection to deal with damage caused by long-term heat accumulation of the IGBT module. The hardware integrates PWM interlocking, drive VGE over-voltage and under-voltage, output overcurrent, and VCE desaturation detection to deal with damage caused by excessive instantaneous loss. Taking IGBT module protection as a system solution, various abnormal working conditions are identified and protected, and the risk of damage can be greatly reduced when the IGBT module is working abnormally. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a structural block diagram of an IGBT module protection system for new energy commercial vehicles of the present invention; Figure 2 This is a structural block diagram of an IGBT module protection circuit for a new energy commercial vehicle of the present invention; Figure 3 It is an overall schematic diagram of the IGBT module protection system of the present invention; Figure 4 It is a connection diagram of the PWM drive circuit of the present invention; Figure 5 It is the PWM drive signal logic diagram of the present invention; Figure 6 It is the PWM drive interlocking logic diagram of the present invention; Figure 7 This is a driving over-voltage and under-voltage protection circuit diagram of the present invention; Figure 8 It is a desaturation detection circuit diagram of the present invention; Fig. 9 Schematic diagram of thermal resistance equivalent model of the present invention; Fig.10 The IGBT module of the present invention Data sheet. DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] like Figure 1-Figure 10 As shown, the technical solution adopted by the present invention is as follows: a new energy commercial vehicle IGBT module protection system, including: an IGBT module, a PWM drive interlock module, a drive over-voltage and under-voltage protection module, an overcurrent protection module, a short-circuit protection module, and an over-temperature and overload protection module.

[0016] like Figure 1 As shown, the first end of the PWM drive interlock module is connected to the second end of the over-temperature and overload protection module, the second end of the PWM drive interlock module is connected to the first end of the drive over- and under-voltage protection module, the third end of the PWM drive interlock module is connected to the second end of the overcurrent protection module, the first end of the IGBT module is connected to the second end of the drive over- and under-voltage protection module and the second end of the short-circuit protection module, the second end of the IGBT module is connected to the first end of the over-temperature and overload protection module, and the third end of the IGBT module is connected to the first end of the overcurrent protection module and the first end of the short-circuit protection module.

[0017] like Figure 2 As shown, the PWM drive interlocking module is a DSP module, and a first end of the DSP module is connected to a second end of the IGBT drive module.

[0018] The driving over-voltage and under-voltage protection module comprises a driving over-voltage and under-voltage protection circuit and an IGBT driving module, wherein the driving over-voltage and under-voltage protection circuit is connected to a first end of the IGBT driving module.

[0019] The overcurrent protection module includes a Hall current sampling module and a hardware overcurrent comparison module.

[0020] The first end of the Hall current sampling module is connected to the third end of the IGBT module, the second end of the Hall current sampling module is connected to the second end of the hardware overcurrent comparison module, and one end of the hardware overcurrent comparison module is connected to the second end of the DSP module.

[0021] The short circuit protection module includes a short circuit, a first end of the short circuit is connected to the first end of the IGBT module and the third end of the IGBT driving module, and a second end of the short circuit is connected to the third end of the IGBT module and the first end of the Hall current sampling module.

[0022] The over-temperature overload protection module includes an IGBT temperature sampling module, the IGBT module includes a thermistor NTC, a first end of the IGBT temperature sampling module is connected to the second end of the IGBT module, and a second end of the IGBT temperature sampling module is connected to the third end of the DSP module.

[0023] like Figure 4 As shown, the microcontroller in the DSP module contains PWM output ports and Output port, the IGBT driver module includes a first driver and a second driver, and the first driver and the second driver each include an IP port, an IN port, and an output port.

[0024] The PWM output port is connected to the IP port of the first driver and the IN port of the second driver. The output port is connected to the IN port of the first driver and the IP port of the second driver.

[0025] like Figure 5 As shown, PWM and PWM are a pair of complementary signals with dead zones, which are inputs to the upper and lower bridges of the IGBT driver module. HS and T IS It is the upper and lower bridge output of the IGBT driver module.

[0026] PWM interlock function such as Figure 6 As shown, when When the PWM is disturbed, and PWM are both high, T HS and T IS It will enter interlock mode, T HS and T IS The driving levels all become low, that is, the upper and lower bridges of the IGBT module are not turned on, preventing short circuit between the bridge arms.

[0027] like Figure 7 As shown, the driving over-voltage and under-voltage protection circuit includes a diode D2, a diode D3, a diode D4, a resistor R1, a resistor R2, a resistor R3, a transistor Q2, a transistor Q3, a first comparator AMP1, a second comparator COMP1, a third comparator COMP2, a Vref1 port, and a Vref2 port; The non-inverting input terminal of the first comparator AMP1 is connected to the collector of the transistor Q2 and the cathode of the diode D4, the base of the transistor Q2 is connected to the base of the transistor Q3, the emitter of the transistor Q2 is connected to the collector of the transistor Q3 and one end of the resistor R1, the other end of the resistor R1 is connected to the anode of the diode D4, the cathode of the diode D2, and the IGBT driving module, the anode of the diode D2 is connected to the anode of the diode D3, the cathode of the diode D3 is connected to the inverting input terminal of the first comparator AMP1, the emitter of the transistor Q3, and the pin U_L_E of the IGBT module, and the resistor R1 is connected to the anode of the diode D4, the cathode of the diode D2, and the IGBT driving module. One end of resistor R2 is connected to a 5V power supply and resistor R3, the other end of resistor R2 is connected to pin TZ3 of the DSP module and the output end of the third comparator COMP2, the other end of resistor R3 is connected to pin TZ4 of the DSP module and the output end of the second comparator COMP1, the inverting input end of the second comparator COMP1 is connected to the Vref1 port, the non-inverting input end of the second comparator COMP1 is connected to the output end of the first comparator AMP1 and the inverting input end of the third comparator COMP2, and the non-inverting input end of the third comparator COMP2 is connected to the Vref2 port.

[0028] Figure 7 The transistor Q1 in the circuit is an IGBT module, and the pin U_L_G of the transistor Q1 is an IGBT driver module. The over-voltage and under-voltage protection is to make the voltage of the pin U_L_G of the IGBT module between +20V and -20V. The active clamping device for over-voltage and under-voltage protection is a bidirectional TVS composed of diodes D2 and D3, with a clamping voltage of 17.8V~20.5V and -17.8V~20.5V. At the same time, diode D4 can clamp the voltage to the UL+ port. The passive detection consists of the first comparator AMP1, the second comparator COMP1, and the third comparator COMP2. The driving power supply of the IGBT module pin U_L_G is the voltage of the UL+ port and the voltage of the UL- port. The power supply voltage is detected by the operational amplifier. When the input voltage UL+ is lower than the reference voltage Vref1, the second comparator COMP1 will reverse. When the input voltage UL- is higher than the reference voltage Vref2, the third comparator COMP2 will reverse. The second comparator COMP1 and the third comparator COMP2 are push-pull outputs. The UVLO port is connected to the TZ4 pin of the DSP module to transmit the driving undervoltage lockout fault signal. The OVLO port is connected to the TZ3 pin of the DSP module to transmit the driving overvoltage lockout fault signal. When the DSP module receives the driving undervoltage lockout fault signal or transmits the driving overvoltage lockout fault signal, it immediately turns off the driving PWM signal and , as well as upload driver over-voltage or under-voltage lockout faults to prevent damage to the module.

[0029] like Figure 3As shown, the hardware overcurrent comparison module includes a fourth comparator COMP3 and a Vref port.

[0030] The second end of the Hall current sampling module is connected to the inverting input end of the fourth comparator COMP3, the non-inverting input end of the fourth comparator COMP3 is connected to the Vref port, and the output end of the fourth comparator COMP3 is connected to the TZ6 pin of the DSP module.

[0031] The output current of the IGBT module passes through the Hall current sampling module, converting the current signal into a voltage signal. The voltage signal is compared with the reference voltage Vref of the fourth comparator COMP3. When the reference voltage Vref threshold is exceeded, the fourth comparator COMP3 is reversed, and the DSP module uploads the hardware overcurrent fault, and at the same time shuts down the drive PWM and The DSP module determines the output current by collecting the voltage signal output by the Hall current sensor. The current safety threshold is pre-set in the DSP module. When the collected current exceeds the set current, the driver PWM and Signal, upload software and hardware overcurrent fault at the same time.

[0032] The current safety threshold is preset in the DSP module as a supplement to the hardware overcurrent comparison protection module fault. The hardware overcurrent fault directly shuts down the driver PWM and , which is faster than program judgment execution.

[0033] The hardware overcurrent comparison protection module detects the overcurrent signal as a spike type. After the current collection in the overcurrent signal is filtered, the DSP module reacts more slowly to the spike type overcurrent signal. When the hardware overcurrent protection fails, protection is provided by pre-setting the current safety threshold in the DSP module.

[0034] like Figure 8 As shown, the short-circuit protection circuit includes: a resistor R4, a diode D1, a diode D5, a transistor Q4, a capacitor C1, a Vref3 port, a fifth comparator COMP4, a VCE desaturation port, and a TIs port.

[0035] The UL+ port is connected to the non-inverting input terminal of the fifth comparator COMP4, the drain of the transistor Q4, the input terminal of the capacitor C1, and the input terminal of the resistor R4. The inverting input terminal of the fifth comparator COMP4 is connected to the Vref3 port. The output terminal of the fifth comparator COMP4 is connected to the VCE desaturation port. The gate of the transistor Q4 is connected to the cathode of the diode D5. The TIs port is connected to the anode of the diode D5 and the IGBT driving module. The source of the transistor Q4 is connected to the output terminal of the capacitor C1 and the U_L_E pin of the IGBT module. The output terminal of the resistor R1 is connected to the anode of the diode D1, and the cathode of the diode D1 is connected to the U_L_C pin of the IGBT module.

[0036] Figure 8 In the figure, transistor Q1 represents the IGBT module, and transistor Q1 pin U_L_G represents the IGBT driver module. When the IGBT module is short-circuited, the current in the IGBT module rises sharply to 5 times the rated current. When the current stops increasing, the voltage across the IGBT module rises to the bus voltage, and the IGBT module enters the desaturation state. By detecting the voltage across the IGBT module when it is turned on, it can be determined whether the IGBT module is short-circuited.

[0037] When the voltage at the TIs port is high, the IGBT module is turned on, the transistor Q4 is turned on, and the current at the UL+ port charges the capacitor C1, with a voltage of Vdesat. Vdesat=Idesat*R1+VF+Vce, where Idesat is the current provided by the UL+ port, VF is the voltage drop of the D1 tube, and Vce is the voltage across the IGBT module.

[0038] When a short circuit occurs, the voltage across the IGBT module increases, and the voltage at the in-phase input of the fifth comparator COMP4 also increases. When the voltage at the in-phase input of the fifth comparator COMP4 is higher than the reference voltage Vref3, the fifth comparator COMP4 is triggered to output a Vce desaturation signal. After the DSP module detects the Vce desaturation signal, it turns off the drive PWM and The short-circuit fault is uploaded simultaneously to prevent the IGBT module from being damaged by continuous short-circuit.

[0039] like Figure 3 As shown, the IGBT temperature sampling module is connected to the thermistor NTC.

[0040] The IGBT temperature sampling module converts the change of thermistor NTC resistance into a voltage signal, collects the temperature of the IGBT module through the DSP module, and estimates the temperature of the IGBT module chip and diode through the junction temperature using the thermal impedance model. Fig. 9 As shown, the thermal impedance model junction temperature calculation formula is ,in is the total loss of the IGBT module, is the thermal resistance from junction temperature to case temperature, and TC is the case temperature. When the estimated junction temperature exceeds the IGBT module junction temperature derating value, an overtemperature fault will be triggered, limiting power or shutting down.

[0041] As a supplement to over-temperature protection, the overload protection of IGBT module requires the shell temperature as the calculation value and thermal resistance model for junction temperature estimation. The shell temperature sampling time is affected by the filtering parameters and has a certain delay. Fig.10 As shown in the figure, based on the estimated junction temperature curve, an inverse time curve of power and time is made. The junction temperature calculated by power at each point of the inverse time curve is less than the junction temperature derating value. By limiting the power of the IGBT by software, the operating junction temperature of the IGBT module is further protected from being less than the maximum junction temperature derating value.

[0042] The IGBT module protection system detects the current and temperature of the IGBT module through software to perform overcurrent, overload and overtemperature protection to deal with damage caused by long-term heat accumulation of the IGBT module. The hardware integrates PWM interlocking, drive VGE over-voltage and under-voltage, output overcurrent, and VCE desaturation detection to deal with damage caused by excessive instantaneous loss. Taking IGBT module protection as a system solution, various abnormal working conditions are identified and protected, and the risk of damage can be greatly reduced when the IGBT module is working abnormally.

[0043] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A new energy commercial vehicle IGBT module protection system, characterized in that: Including: PWM drive interlock module, drive over-voltage and under-voltage protection module, over-current protection module, short-circuit protection module, over-temperature and overload protection module; The first end of the PWM drive interlock module is connected to the second end of the over-temperature and overload protection module, the second end of the PWM drive interlock module is connected to the first end of the drive over- and under-voltage protection module, the third end of the PWM drive interlock module is connected to the second end of the overcurrent protection module, the first end of the IGBT module is connected to the second end of the drive over- and under-voltage protection module and the second end of the short-circuit protection module, the second end of the IGBT module is connected to the first end of the over-temperature and overload protection module, and the third end of the IGBT module is connected to the first end of the overcurrent protection module and the first end of the short-circuit protection module.

2. A new energy commercial vehicle IGBT module protection system according to claim 1, characterized in that: The driving over-voltage and under-voltage protection module comprises a driving over-voltage and under-voltage protection circuit and an IGBT driving module, wherein the driving over-voltage and under-voltage protection circuit is connected to a first end of the IGBT driving module; The PWM drive interlock module includes a DSP module, a first end of the DSP module is connected to a second end of the IGBT drive module; The overcurrent protection module includes a Hall current sampling module and a hardware overcurrent comparison module; The first end of the Hall current sampling module is connected to the third end of the IGBT module, the second end of the Hall current sampling module is connected to the second end of the hardware overcurrent comparison module, and the first end of the hardware overcurrent comparison module is connected to the second end of the DSP module; The short-circuit protection module includes a short-circuit circuit, a first end of the short-circuit circuit is connected to a first end of the IGBT module and a third end of the IGBT driving module, and a second end of the short-circuit circuit is connected to a third end of the IGBT module and a first end of the Hall current sampling module; The over-temperature and overload protection module comprises an IGBT temperature sampling module, a first end of the IGBT temperature sampling module is connected to the second end of the IGBT module, and a second end of the IGBT temperature sampling module is connected to the third end of the DSP module.

3. The IGBT module protection system for new energy commercial vehicles according to claim 1 is characterized in that: The IGBT module is provided with a thermistor NTC.

4. A new energy commercial vehicle IGBT module protection system according to claim 2, characterized in that: The DSP module contains PWM output ports and Output port, the IGBT driver module includes a first driver and a second driver, and the first driver and the second driver each include an IP port, an IN port, and an output port; The PWM output port is connected to the IP port of the first driver and the IN port of the second driver. The output port is connected to the IN port of the first driver and the IP port of the second driver; The PWM output port outputs a PWM signal, Output port output signal, PWM signal and The signal is a pair of complementary signals with dead zone. When the signal is interfered, PWM signal and When the signals are both at high level, the outputs of the upper and lower bridge arms of the IGBT module enter interlocking mode.

5. The IGBT module protection system for new energy commercial vehicles according to claim 4, characterized in that: The hardware overcurrent comparison module includes a fourth comparator COMP3 and a Vref port; The second end of the Hall current sampling module is connected to the inverting input end of the fourth comparator COMP3, the non-inverting input end of the fourth comparator COMP3 is connected to the Vref port, and the output end of the fourth comparator COMP3 is connected to the TZ6 pin of the DSP module; The output current of the IGBT module passes through the Hall current sampling module, converting the current signal into a voltage signal. The voltage signal is compared with the reference voltage Vref of the fourth comparator COMP3. When the reference voltage Vref threshold is exceeded, the fourth comparator COMP3 is reversed, and the DSP module uploads the hardware overcurrent fault, and at the same time shuts down the drive PWM signal and Signal; A current safety threshold will be pre-set in the DSP module as a supplement to the hardware overcurrent comparison protection module failure. The hardware overcurrent comparison protection module detects the overcurrent signal as a spike type. After the current collection in the overcurrent signal is filtered, the DSP module reacts more slowly to the spike-type overcurrent signal. When the hardware overcurrent protection fails, protection is provided by pre-setting the current safety threshold in the DSP module.

6. The IGBT module protection system for new energy commercial vehicles according to claim 2, characterized in that: The driving over-voltage and under-voltage protection circuit includes a diode D2, a diode D3, a diode D4, a resistor R1, a resistor R2, a resistor R3, a transistor Q2, a transistor Q3, a first comparator AMP1, a second comparator COMP1, a third comparator COMP2, a Vref1 port, and a Vref2 port; The non-inverting input terminal of the first comparator AMP1 is connected to the collector of the transistor Q2 and the cathode of the diode D4, the base of the transistor Q2 is connected to the base of the transistor Q3, the emitter of the transistor Q2 is connected to the collector of the transistor Q3 and one end of the resistor R1, the other end of the resistor R1 is connected to the anode of the diode D4, the cathode of the diode D2, and the IGBT driving module, the anode of the diode D2 is connected to the anode of the diode D3, the cathode of the diode D3 is connected to the inverting input terminal of the first comparator AMP1, the emitter of the transistor Q3, and the pin U_L_E of the IGBT module, and the resistor R1 is connected to the anode of the diode D4, the cathode of the diode D2, and the IGBT driving module. One end of the resistor R2 is connected to a 5V power supply and a resistor R3, the other end of the resistor R2 is connected to a TZ3 pin of the DSP module and an output end of the third comparator COMP2, the other end of the resistor R3 is connected to a TZ4 pin of the DSP module and an output end of the second comparator COMP1, an inverting input end of the second comparator COMP1 is connected to a Vref1 port, a non-inverting input end of the second comparator COMP1 is connected to an output end of the first comparator AMP1 and an inverting input end of the third comparator COMP2, and a non-inverting input end of the third comparator COMP2 is connected to a Vref2 port; When the voltage of the collector of the transistor Q2 is lower than the reference voltage Vref1, the second comparator COMP1 will reverse, and when the voltage of the collector of the transistor Q2 is higher than the reference voltage Vref2, the third comparator COMP2 will reverse. The second comparator COMP1 and the third comparator COMP2 are push-pull outputs. The TZ4 pin of the DSP module transmits a drive undervoltage lockout fault signal, and the TZ3 pin of the DSP module transmits a drive overvoltage lockout fault signal. When the DSP module receives a drive undervoltage lockout fault signal or transmits a drive overvoltage lockout fault signal, it immediately turns off the drive PWM signal and Signal, and upload driver over-voltage or under-voltage lockout fault.

7. The IGBT module protection system for new energy commercial vehicles according to claim 2, characterized in that: The short circuit protection circuit includes: a resistor R4, a diode D1, a diode D5, a transistor Q4, a capacitor C1, a Vref3 port, a fifth comparator COMP4, a VCE desaturation port, and a TIs port; The cathode of the diode D4 is connected to the non-inverting input terminal of the fifth comparator COMP4, the drain of the transistor Q4, the input terminal of the capacitor C1, and the input terminal of the resistor R4, the inverting input terminal of the fifth comparator COMP4 is connected to the Vref3 port, the output terminal of the fifth comparator COMP4 is connected to the VCE desaturation port, the gate of the transistor Q4 is connected to the cathode of the diode D5, the TIs port is connected to the anode of the diode D5 and the IGBT driving module, the source of the transistor Q4 is connected to the output terminal of the capacitor C1 and the U_L_E pin of the IGBT module, the output terminal of the resistor R1 is connected to the anode of the diode D1, and the cathode of the diode D1 is connected to the U_L_C pin of the IGBT module; When a short circuit occurs, the voltage across the IGBT module rises, and the voltage at the in-phase input of the fifth comparator COMP4 also rises. When the voltage at the in-phase input of the fifth comparator COMP4 is higher than the reference voltage Vref3, the fifth comparator COMP4 is triggered to output a Vce desaturation signal. After the DSP module detects the Vce desaturation signal, it turns off the drive PWM signal and signal, while uploading a short circuit fault.

8. The IGBT module protection system for new energy commercial vehicles according to claim 3 is characterized in that: The IGBT temperature sampling module is connected to the thermistor NTC; The IGBT temperature sampling module converts the change in the resistance of the thermistor NTC into a voltage signal, collects the temperature of the IGBT module through the DSP module, and estimates the temperature of the IGBT module chip and diode through the junction temperature using the thermal impedance model. The junction temperature calculation formula of the thermal impedance model is: ,in is the total loss of the IGBT module, is the thermal resistance from junction temperature to case temperature, TC is the case temperature. When the estimated junction temperature exceeds the IGBT module junction temperature derating value, an over-temperature fault will be triggered, limiting power or shutting down.

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