A drive circuit for a SiC module

Abstract

This utility model relates to a drive circuit for a SiC module, belonging to the field of motor controller technology. It is used for electric vehicle drive and includes a safety logic circuit, an upper bridge drive chip, a lower bridge drive chip, a drive circuit, a short-circuit detection circuit, and a temperature detection circuit. The safety logic circuit monitors the current state of the motor controller. The input terminals of the upper and lower bridge drive chips are connected to the safety logic circuit, and the output terminals of the upper and lower bridge drive chips are connected to the drive circuit, the short-circuit detection circuit, and the temperature detection circuit. The advantages of this utility model are: integrated safety protection logic, meeting the current mainstream functional safety requirements of the industry, and capable of achieving ISO26262 ASIL D functional safety level requirements; highly integrated circuit design; and optimized design for high-power, high-voltage SiC devices.

Description

Technical Field

[0001] This utility model relates to a drive circuit for a SiC module, belonging to the field of motor controller technology. Background Technology

[0002] In recent years, the electric vehicle industry has flourished. Consumers' demands for vehicle range and performance are constantly increasing, prompting automakers to seek more efficient motor drive solutions. Traditional silicon-based devices are gradually showing limitations in handling high-power, high-frequency requirements, while silicon carbide devices, with their significant advantages, have become a key force driving innovation in motor drive technology.

[0003] In terms of material properties, silicon carbide is a third-generation semiconductor material. Its bandgap is about three times that of silicon-based materials, its breakdown field strength is about ten times that of silicon, and its thermal conductivity is about three times that of silicon. These properties enable silicon carbide devices to operate stably in high-voltage and high-temperature environments.

[0004] In electric motor drive systems, silicon carbide (SiC) devices demonstrate significant advantages. Taking inverters as an example, SiC MOSFETs exhibit lower switching losses than traditional silicon IGBTs. In a 400V system, the former can achieve approximately 50% loss reduction while maintaining high efficiency at high frequencies, thereby improving the efficiency of the electric drive system in converting battery energy into vehicle power. The high switching frequency of SiC modules reduces the size of passive components such as inductors and capacitors; using SiC modules can reduce the size of these components by 30%-50%.

[0005] Despite the significant advantages of silicon carbide (SiC) devices, their application in electric vehicle motor drives still faces challenges. On one hand, manufacturing costs are high, with complex processes from material purification to processing increasing overall costs. On the other hand, packaging technology is immature; SiC devices operate at high frequencies and generate significant heat, and existing packaging methods struggle to meet the requirements for heat dissipation and electrical isolation, limiting their performance. Furthermore, the drive and control technologies adapted to SiC devices require further optimization. Utility Model Content

[0006] To overcome the shortcomings of the prior art, this utility model provides a driving circuit for a SiC module that meets the requirements of electric vehicle drive for high functional safety level, high reliability, and high integration.

[0007] This utility model is achieved through the following technical solution: a SiC module drive circuit for electric vehicle drive, including a safety logic circuit, an upper bridge drive chip, a lower bridge drive chip, a drive circuit, a short circuit detection circuit, and a temperature detection circuit.

[0008] The aforementioned safety logic circuit is used to monitor the current status of the motor controller;

[0009] The input terminals of the upper bridge driver chip and the lower bridge driver chip are connected to a safety logic circuit, and the output terminals of the upper bridge driver chip and the lower bridge driver chip are connected to the driving circuit, the short circuit detection circuit and the temperature detection circuit.

[0010] Preferably, when the safety logic circuit detects that the MCU has crashed or other faults, it outputs a trigger signal to the upper bridge driver chip and the lower bridge driver chip. When SI1 / SI2 is equal to 10 or 01, the upper or lower MOSFET is forcibly turned on, while the other side is turned off, so that the controller enters ASC mode.

[0011] Preferably, the short-circuit detection circuit includes diode D1, diode D2, Zener diode D3, resistor R1, and capacitor C1. The other end of capacitor C1, resistor R1, and the negative terminal of diode D3 are connected to the DESAT pin of the driver chip. The positive terminals of capacitor C1 and diode D3 are grounded. The other end of resistor R1 is connected to the positive terminal of diode D1. The negative terminal of diode D1 is connected to the positive terminal of diode D2. The negative terminal of diode D2 serves as the output terminal. The short-circuit detection circuit is set to have a short-circuit protection time of less than 2µs. When a short-circuit fault occurs, the driver chip shuts down the silicon carbide device, and at the same time, the fault pin of the driver chip is pulled low, reporting the fault to the control unit.

[0012] Preferably, the temperature detection circuit includes resistors R4, R5, and R6, capacitor C2, and a thermistor NTC. The high-voltage side AIP / SASC pin of the driver chip is connected to resistor R4 and capacitor C2. The other end of resistor R4 is connected to resistors R5, R6, and the thermistor NTC. The other ends of capacitor C2, resistor R6, and thermistor NTC are grounded. The temperature detection circuit transmits temperature data to the MCU through the driver chip.

[0013] Preferably, the driving circuit includes an on-resistance R7, an off-resistance R8, a soft-off resistor R9, a Miller clamping resistor R10, a resistor R11, a capacitor C3, and a gate resistor-capacitor-TVS clamp. The on-resistance R7 is connected to the TON pin of the driving chip, the off-resistance R8 is connected to the TOFF pin of the driving chip, the soft-off resistor R9 is connected to the SOFTOFF pin of the driving chip, and the Miller clamping resistor R10 is connected to the GATE / CLAMP pin of the driving chip. The other ends of the on-resistance R7, off-resistance R8, soft-off resistor R9, and Miller clamping resistor R10 are connected to the resistor R11, capacitor C3, gate resistor-capacitor-TVS clamp, and output terminal G. The other ends of the resistor R11, capacitor C3, and gate resistor-capacitor-TVS clamp are connected to the output terminal S.

[0014] Preferably, the upper bridge driver chip and the lower bridge driver chip are insulated gate bipolar transistor chips 1EDI3035AS.

[0015] The beneficial effects of this utility model are: it integrates safety protection logic, meets the current mainstream functional safety requirements of the industry, and can be used with the system to achieve the ISO26262 ASIL D functional safety level requirements; it features a highly integrated circuit design; and it is optimized for high-power, high-voltage SiC devices. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] Figure 1 This is the circuit schematic diagram of this utility model;

[0018] Figure 2 This is a schematic diagram of the fault detection circuit of this utility model;

[0019] Figure 3 This is a schematic diagram of the temperature detection circuit of this utility model;

[0020] Figure 4 This is the schematic diagram of the driving circuit of this utility model. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model; the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In addition, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0023] like Figure 1The diagram shows a SiC module drive circuit for electric vehicle drive, including a safety logic circuit, an upper bridge drive chip, a lower bridge drive chip, a drive circuit, a short circuit detection circuit, and a temperature detection circuit.

[0024] The aforementioned safety logic circuit is used to monitor the current status of the motor controller;

[0025] The input terminals of the upper bridge driver chip and the lower bridge driver chip are connected to a safety logic circuit, and the output terminals of the upper bridge driver chip and the lower bridge driver chip are connected to the driving circuit, the short circuit detection circuit and the temperature detection circuit.

[0026] Preferably, when the safety logic circuit detects that the MCU has crashed or other faults, it outputs a trigger signal to the upper bridge driver chip and the lower bridge driver chip. When SI1 / SI2 is equal to 10 or 01, the upper or lower MOSFET is forcibly turned on, while the other side is turned off, so that the controller enters ASC mode. The logic truth table is shown below.

[0027]

[0028] like Figure 2 The short-circuit detection circuit shown includes diodes D1 and D2, Zener diode D3, resistor R1, and capacitor C1. The other end of capacitor C1, resistor R1, and the negative terminal of diode D3 are connected to the DESAT pin of the driver chip. The positive terminals of capacitor C1 and diode D3 are grounded. The other end of resistor R1 is connected to the positive terminal of diode D1. The negative terminal of diode D1 is connected to the positive terminal of diode D2. The negative terminal of diode D2 serves as the output terminal. When a short-circuit fault occurs, the DS voltage of the SIC module increases, and the voltage of the DESAT pin of the driver chip also increases. When the DESAT pin voltage exceeds the protection threshold, a DESAT fault is triggered. The driver chip shuts down the silicon carbide device, and the fault pin of the driver chip is pulled low, reporting the fault to the control unit. Preferably, by adjusting the capacitance of capacitor C1, the short-circuit protection time of the short-circuit detection circuit is made within 2µs.

[0029] like Figure 3The temperature detection circuit shown includes resistors R4, R5, and R6, capacitor C2, and a thermistor NTC. The high-voltage side AIP / SASC pin of the driver chip is connected to resistor R4 and capacitor C2. The other end of resistor R4 is connected to resistors R5, R6, and the thermistor NTC. The other ends of capacitor C2, resistor R6, and thermistor NTC are grounded. Resistor R6 and thermistor NTC are connected in parallel and then connected in series with resistor R5 to divide the voltage. The voltage value after voltage division is filtered by the RC filter circuit composed of resistor R4 and capacitor C2 and then enters the AIP / SASC pin of the driver chip. The voltage value entering the driver chip must be within the range of analog signal acquisition. The temperature detection circuit transmits the temperature data to the MCU through the driver chip. Preferably, the power supply voltage of the temperature detection circuit is 5V.

[0030] like Figure 4 The driving circuit shown includes an on-resistance R7, an off-resistance R8, a soft-off resistor R9, a Miller clamp resistor R10, a resistor R11, a capacitor C3, and a gate resistor-capacitor-TVS clamp. The on-resistance R7 is connected to the TON pin of the driving chip, the off-resistance R8 is connected to the TOFF pin of the driving chip, the soft-off resistor R9 is connected to the SOFTOFF pin of the driving chip, and the Miller clamp resistor R10 is connected to the GATE / CLAMP pin of the driving chip. The other ends of the on-resistance R7, off-resistance R8, soft-off resistor R9, and Miller clamp resistor R10 are connected to the resistor R11, capacitor C3, gate resistor-capacitor-TVS clamp, and output terminal G. The other ends of the resistor R11, capacitor C3, and gate resistor-capacitor-TVS clamp are connected to the output terminal S.

[0031] When the silicon carbide module is turned on, the TON pin is at a high level, driving the silicon carbide module to conduct. Resistor R7 is the turn-on current limiting resistor. The dv / dt at turn-on can be adjusted by adjusting the resistance value of resistor R7. Preferably, resistor R7 is an anti-pulse resistor.

[0032] When the silicon carbide module is turned off, the TOFF pin is at a low level, which drives the silicon carbide module to shut down. Resistor R8 is a shutdown current limiting resistor. The dv / dt at shutdown can be adjusted by adjusting the resistance value of resistor R7. Preferably, resistor R8 is an anti-pulse resistor.

[0033] Resistor R9 is a soft-shutdown current-limiting resistor, which reduces the shutdown speed when the silicon carbide module fails and avoids overvoltage.

[0034] Resistor R10 is a Miller clamp current limiting resistor, which effectively suppresses voltage spikes caused by transistor switching during gate drive. Preferably, resistor R10 is 0Ω.

[0035] Preferably, the upper bridge driver chip and the lower bridge driver chip are insulated gate bipolar transistor chips 1EDI3035AS.

[0036] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A driving circuit for a SiC module, characterized in that: Used for electric vehicle drives, including safety logic circuits, upper bridge driver chips, lower bridge driver chips, drive circuits, short circuit detection circuits, and temperature detection circuits; The aforementioned safety logic circuit is used to monitor the current status of the motor controller; The input terminals of the upper bridge driver chip and the lower bridge driver chip are connected to a safety logic circuit, and the output terminals of the upper bridge driver chip and the lower bridge driver chip are connected to the driving circuit, the short circuit detection circuit and the temperature detection circuit.

2. The driving circuit for a SiC module according to claim 1, characterized in that: When the safety logic circuit detects that the MCU has crashed or other faults, it outputs a trigger signal to the upper bridge driver chip and the lower bridge driver chip. When SI1 / SI2 is equal to 10 or 01, the upper or lower MOSFET is forcibly turned on, while the other side is turned off, so that the controller enters ASC mode.

3. The driving circuit for a SiC module according to claim 1, characterized in that: The short-circuit detection circuit includes diodes D1 and D2, Zener diode D3, resistor R1, and capacitor C1. The other end of capacitor C1, resistor R1, and the negative terminal of diode D3 are connected to the DESAT pin of the driver chip. The positive terminals of capacitor C1 and diode D3 are grounded. The other end of resistor R1 is connected to the positive terminal of diode D1. The negative terminal of diode D1 is connected to the positive terminal of diode D2. The negative terminal of diode D2 serves as the output terminal. The short-circuit detection circuit is set to provide short-circuit protection within 2µs. When a short-circuit fault occurs, the driver chip shuts down the silicon carbide device, and the fault pin of the driver chip is pulled low, reporting the fault to the control unit.

4. The driving circuit for a SiC module according to claim 1, characterized in that: The temperature detection circuit includes resistors R4, R5, and R6, capacitor C2, and thermistor NTC. The high-voltage side AIP / SASC pin of the driver chip is connected to resistor R4 and capacitor C2. The other end of resistor R4 is connected to resistors R5, R6, and thermistor NTC. The other ends of capacitor C2, resistor R6, and thermistor NTC are grounded. The temperature detection circuit transmits temperature data to the MCU through the driver chip.

5. The driving circuit for a SiC module according to claim 1, characterized in that: The driving circuit includes an on-resistor R7, an off-resistor R8, a soft-off resistor R9, a Miller clamp resistor R10, a resistor R11, a capacitor C3, and a gate resistor-capacitor-TVS clamp. The on-resistor R7 is connected to the TON pin of the driving chip, the off-resistor R8 is connected to the TOFF pin of the driving chip, the soft-off resistor R9 is connected to the SOFTOFF pin of the driving chip, and the Miller clamp resistor R10 is connected to the GATE / CLAMP pin of the driving chip. The other ends of the on-resistor R7, off-resistor R8, soft-off resistor R9, and Miller clamp resistor R10 are connected to the resistor R11, capacitor C3, gate resistor-capacitor-TVS clamp, and output terminal G. The other ends of the resistor R11, capacitor C3, and gate resistor-capacitor-TVS clamp are connected to the output terminal S.

6. The driving circuit for a SiC module according to claim 1, characterized in that: The upper bridge driver chip and the lower bridge driver chip are insulated gate bipolar transistor chips 1EDI3035AS.

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