DE-102025146288-A1 - Active short-circuit protection circuit for vehicles, EMB system, EPS system and protection method

DE102025146288A1DE 102025146288 A1DE102025146288 A1DE 102025146288A1DE-102025146288-A1

Abstract

The present invention discloses an active short-circuit protection circuit for vehicles, an EMB system, an EPS system, and a protection method. The active short-circuit protection circuit for vehicles is applied to a main circuit comprising a battery, an inverter, a gate driver module for driving the inverter, and a motor; wherein the active short-circuit protection circuit for vehicles comprises: a PWM output switching module connected in series between the output terminal of the gate driver module and the control terminals of each lower bridge branch switching transistor of the inverter; a short-circuit protection switching module and a short-circuit protection power supply module, wherein the short-circuit protection power supply module is supplied by the battery and generates a voltage suitable for the lower bridge branch switching transistors; wherein the short-circuit protection switching module is connected in series between the short-circuit protection power supply module and the control terminals of each lower bridge branch switching transistor. The short-circuit protection module switches on when the battery voltage exceeds a defined threshold and controls the switching on of the lower bridge branch switching transistors, thus coupling the individual stator windings of the motor. The embodiments of the present invention enable the effective elimination of faults in the line.

Inventors

Yan Lv
Fei Yang
Haifeng Hu

Assignees

NEXTEER AUTOMOTIVE (SUZHOU) CO., LTD.

Dates

Publication Date: 20260513
Application Date: 20251110
Priority Date: 20241111

Claims (20)

Active short-circuit protection circuit for a vehicle, applied to a main circuit comprising a battery, an inverter, a gate driver module for controlling the inverter, and a motor, wherein the active short-circuit protection circuit for a vehicle comprises: a pulse-width modulation (PWM) output switching module connected between an output terminal of the gate driver module and a control terminal of each of the switching transistors of the lower bridge branch of the inverter in a series-connected short-circuit protection switching module and a short-circuit protection power supply module, wherein the short-circuit protection power supply module is powered by the battery and converts the supplied current into a voltage suitable for each of the switching transistors of the lower bridge branch, wherein the short-circuit protection switching module is connected in series between the short-circuit protection power supply module and the control terminal of each of the switching transistors of the lower bridge branch, and the short-circuit protection switching module is turned on when the voltage of the battery exceeds a certain threshold to control that each of the switching transistors of the lower bridge branch is turned on, so that stator windings of the motor are coupled; wherein the PWM output switching module and the short-circuit protection switching module are not turned on simultaneously.
Active short-circuit protection circuit according to Claim 1 , wherein the motor is a three-phase motor and the inverter comprises a first switching transistor of the lower bridge branch, a second switching transistor of the lower bridge branch and a third switching transistor of the lower bridge branch; the PWM output switching module comprises a first PWM output switch, a second PWM output switch and a third PWM output switch, wherein the first PWM output switch is connected in series between a first control output terminal of the lower bridge branch of the gate driver module and the control terminal of the first switching transistor of the lower bridge branch, the second PWM output switch is connected in series between a second control output terminal of the lower bridge branch of the gate driver module and the control terminal of the second switching transistor of the lower bridge branch, and the third PWM output switch is connected in series between a third control output terminal of the lower bridge branch of the gate driver module and the control terminal of the third switching transistor of the lower bridge branch; and/or the short-circuit protection switching module comprises a first short-circuit protection switch, a second short-circuit protection switch and a third short-circuit protection switch, wherein the first short-circuit protection switch is connected in series between the short-circuit protection power supply module and the control terminal of the first switching transistor of the lower bridge branch, the second short-circuit protection switch is connected in series between the short-circuit protection power supply module and the control terminal of the second switching transistor of the lower bridge branch, and the third short-circuit protection switch is connected in series between the short-circuit protection power supply module and the control terminal of the third switching transistor of the lower bridge branch.
Active short-circuit protection circuit according to Claim 1 , further comprising: a short-circuit protection activation module, wherein the short-circuit protection activation module outputs a PWM output blocking signal and a short-circuit enabling signal based on a short-circuit enabling signal; a PWM output blocking module connected between the short-circuit protection activation module and the PWM output enabling module, wherein the PWM output blocking module is configured to generate a control signal based on the PWM output blocking signal to control the PWM output enabling module to be switched off; and a short-circuit protection output activation module connected between the short-circuit protection activation module and the short-circuit protection enabling module, wherein the short-circuit protection output activation module is configured to generate a control signal based on the short-circuit enabling signal to control the short-circuit protection enabling module so that it switches on.
Active short-circuit protection circuit according to Claim 3 , further comprising: a voltage sensing module coupled to the battery, wherein the voltage sensing module is configured to detect a positive electrode voltage of the battery; and a main control module connected between the voltage sensing module and the short-circuit protection activation module, wherein the main control module is configured to output the short-circuit release signal when the positive electrode voltage exceeds the specified threshold.
Active short-circuit protection circuit according to Claim 3 , further comprising: a circuit status monitoring module coupled to the short-circuit protection activation module and the PWM output blocking module, wherein the circuit status monitoring module is configured to monitor the operating status of the short-circuit protection activation module and the PWM output blocking module and to report it back to the main control module.
Active short-circuit protection circuit according to Claim 1 , wherein the output terminal of the gate drive module is directly coupled to each of the switching transistors of the upper bridge branch of the inverter; and The PWM output blocking module is further coupled to the gate control module and is configured to control each of the switching transistors of the upper bridge branch to be turned off based on the PWM output blocking signal.
Active short-circuit protection circuit according to Claim 1 , further comprising: a phase output status monitoring module coupled to the stator windings of the motor, wherein the phase output status monitoring module is configured to monitor a voltage of the stator windings of the motor and report it back to the main control module.
Active short-circuit protection circuit according to Claim 1 , where the main circuit is assigned to an electromechanical braking system.
Active short-circuit protection circuit according to Claim 1 , where the main circuit is assigned to an electronic power steering system.
Active short-circuit protection circuit according to Claim 1 , wherein the short-circuit protection switching module: receives a positive electrode voltage from the battery; and when the positive electrode voltage of the battery exceeds a certain threshold: controls one or more switching transistors of the upper bridge branch of the inverter to be switched off; and controls each of the switching transistors of the lower bridge branch of the inverter to be switched on, so that the stator windings of the motor are coupled.
Active short-circuit protection circuit comprising: a pulse-width modulation (PWM) output switching module, comprising a first PWM output switch connected in series between a first control output terminal of the lower bridge branch of a gate driver module, a second PWM output switch connected in series between a second control output terminal of the lower bridge branch of the gate driver module, and a third PWM output switch connected in series between a third control output terminal of the lower bridge branch of the gate driver module; a short-circuit protection power supply module configured to convert the battery voltage into a respective voltage at each of the first control output terminal of the lower bridge branch, the second control output terminal of the lower bridge branch, and the third control output terminal of the lower bridge branch; and a short-circuit protection switching module that is switched on in response to the battery voltage exceeding a threshold, causing respective transistors of each of the first control output terminal of the lower bridge branch, the second control output terminal of the lower bridge branch and the third control output terminal of the lower bridge branch to conduct and couple stator windings of an associated motor.
Active short-circuit protection circuit according to Claim 11 , where the motor is assigned to an electromechanical braking system.
Active short-circuit protection circuit according to Claim 11 , where the engine is assigned to an electronic power steering system.
Active short-circuit protection circuit according to Claim 11 , furthermore including a short-circuit protection activation module.
Active short-circuit protection circuit according to Claim 14 , wherein the short-circuit protection activation module outputs a PWM output blocking signal and a short-circuit switching enable signal based on a short-circuit enable signal.
Active short-circuit protection circuit according to Claim 14 , furthermore comprising a PWM output blocking module that is connected between the short-circuit protection activation module and the PWM output switching module.
Active short-circuit protection circuit according to Claim 16 , wherein the PWM output blocking module is configured to generate a control signal to control the PWM output switching module based on the PWM output blocking signal, causing it to switch off.
Active short-circuit protection circuit according to Claim 16 , further comprising a short-circuit protection output activation module that is connected between the short-circuit protection activation module and the short-circuit protection switching module.
Active short-circuit protection circuit according to Claim 18 , wherein the short-circuit protection output activation module is configured to generate a control signal to control the short-circuit protection switching module based on the short-circuit switch enable signal, so that it switches on.
Active short-circuit protection method, comprising: a pulse width modulation (PWM) output switching module comprising a first PWM output switch connected in series between a first control output terminal of the lower bridge branch of a gate drive module, a second PWM output switch connected in series between a second control output terminal of the lower bridge branch of the gate drive module, and a third PWM output switch connected in series between a third control output terminal of the lower bridge branch of the gate drive module; Converting, using a short-circuit protection power supply module, battery voltage into a respective voltage at each of a first control output terminal of the lower bridge branch of a pulse width modulation (PWM) output switching module, a second control output terminal of the lower bridge branch of the PWM output switching module, and the third control output terminal of the lower bridge branch of the PWM output switching module, wherein the PWM output switching module comprises a first PWM output switch connected in series between the first control output terminal of the lower bridge branch of a gate driver module, a second PWM output switch connected in series between the second control output terminal of the lower bridge branch of the gate driver module, and a third PWM output switch connected in series between the third control output terminal of the lower bridge branch of the gate driver module; and in response to the battery voltage exceeding a threshold, switching on a short-circuit protection switching module, which causes (i) respective transistors of each of the first control output terminal of the lower bridge branch, the second control output terminal of the lower bridge branch and the third control output terminal of the lower bridge branch to conduct and (ii) coupling stator windings of an associated motor.

Description

AREA OF INVENTION The present invention relates to the technical field of motor control and in particular to an active short-circuit protection circuit for vehicles, an EMB system, an EPS system and a protection method. STATE OF THE ART With the rapid development of new energy vehicles, the safety requirements for these vehicles are constantly increasing. New energy vehicles are typically powered by battery-driven motors. When the battery supplies power to the electric motor, faults in the circuit or excessive back EMF from the motor can damage the switching transistors in the circuit. This can exacerbate the fault and seriously compromise the safe operation of the new energy vehicle. To effectively eliminate faults in vehicle electrical circuits, the protective devices used in existing technology generally act directly on the individual switching transistors via a control signal, thus achieving fault elimination by controlling the individual switching transistors. However, this configuration has a low level of safety and can easily lead to faults not being effectively eliminated due to a failure of the control signal. REVELATION OF THE INVENTION The present invention provides an active short-circuit protection circuit for vehicles, an EMB system, an EPS system and a protection method to solve the problem that faults in the line cannot be effectively switched off. According to one aspect of the present invention, an active short-circuit protection circuit for vehicles is provided, which is applied to a main circuit comprising a battery, an inverter, a gate driver module for driving the inverter, and a motor; wherein the active short-circuit protection circuit for vehicles comprises: a PWM output switching module connected in series between the output terminal of the gate driver module and the control terminals of the individual lower bridge branch switching transistors of the inverter; a short-circuit protection switching module and a short-circuit protection power supply module, wherein the short-circuit protection power supply module is powered by the battery and generates a voltage suitable for the lower bridge branch switching transistors; wherein the short-circuit protection switching module is connected in series between the short-circuit protection power supply module and the control terminals of the individual lower bridge branch switching transistors; wherein the short-circuit protection switching module turns on when the battery voltage exceeds a specified threshold and controls the turning on of the lower bridge branch switching transistors, thus coupling the individual stator windings of the motor; the PWM output switching module and the short-circuit protection switching module do not switch on simultaneously. Optionally, the motor is a three-phase motor and the inverter includes a first lower bridge branch switching transistor, a second lower bridge branch switching transistor and a third lower bridge branch switching transistor; wherein the PWM output switching module comprises a first PWM output switch, a second PWM output switch, and a third PWM output switch; wherein the first PWM output switch is connected in series between the control output terminal of the first lower bridge branch of the gate driver module and the control terminal of the first lower bridge branch switching transistor; wherein the second PWM output switch is connected in series between the control output terminal of the second lower bridge branch of the gate driver module and the control terminal of the second lower bridge branch switching transistor; wherein the third PWM output switch is connected in series between the control output terminal of the third lower bridge branch of the gate driver module and the control terminal of the third lower bridge branch switching transistor; and/or wherein the short-circuit protection switching module comprises a first short-circuit protection switch, a second short-circuit protection switch, and a third short-circuit protection switch; wherein the first short-circuit protection switch is connected in series between the short-circuit protection power supply module and the control terminal of the first lower bridge branch switching transistor; wherein the second short-circuit protection switch is connected in series between the short-circuit protection power supply module and the control terminal of the second lower bridge branch switching transistor; wherein the third short-circuit protection switch is connected in series between the short-circuit protection power supply module and is connected to the control terminal of the third lower bridge branch switching transistor. Optionally, the active short-circuit protection circuit for vehicles also includes: a short-circuit protection activation module, wherein the short-circuit protection activation module outputs a PWM output deactivation signal and a short-circuit switch activation signal according to a short-circuit activation sig