Active short-circuit protection circuit for vehicle, EMB system, EPS system and protection method

Abstract

The invention discloses a vehicle active short circuit protection circuit, an EMB system, an EPS system and a protection method. The active short-circuit protection circuit for the vehicle is applied to a main circuit comprising a battery, an inverter, a gate driving module for driving the inverter and a motor. The active short-circuit protection circuit for the vehicle comprises a PWM output switch module which is connected in series between the output end of a gate pole driving module and the control end of each lower bridge arm switch tube of an inverter; the short-circuit protection power supply module is powered by a battery and is converted into voltage matched with each lower bridge arm switch tube; the short-circuit protection switch module is connected in series between the short-circuit protection power supply module and the control end of each lower bridge arm switch tube; and the short-circuit protection switch module is switched on when the voltage of the battery exceeds a set threshold value, and each lower bridge arm switch tube is controlled to be switched on, so that each stator winding of the motor is coupled. According to the embodiment of the invention, the fault in the line can be effectively removed.

Description

Technical Field

[0001] This invention relates to the field of motor control technology, and in particular to an active short-circuit protection circuit, EMB system, EPS system, and protection method for vehicles. Background Technology

[0002] With the rapid development of new energy vehicles, people's safety requirements for these vehicles are also constantly increasing. New energy vehicles generally use batteries to drive motors to propel the vehicle. When the battery supplies power to the motor, faults in the power supply line or excessive back electromotive force from the motor can damage the switching transistors in the line, thus exacerbating the fault and seriously affecting the safe operation of the new energy vehicle.

[0003] In order to effectively isolate faults in automotive circuits, existing protection devices generally act directly on each switch transistor through control signals, thereby isolating the fault by controlling each switch transistor. However, this method has a low safety level and is prone to failure of control signals, which can lead to the inability to effectively isolate the fault. Summary of the Invention

[0004] This invention provides an active short-circuit protection circuit, an EMB system, an EPS system, and a protection method for vehicles to solve the problem that faults in the circuit cannot be effectively isolated.

[0005] According to one aspect of the present invention, an active short-circuit protection circuit for vehicles is provided, applied to a main circuit comprising a battery, an inverter, a gate drive module for driving the inverter, and a motor; the active short-circuit protection circuit for vehicles includes:

[0006] A PWM output switching module is connected in series between the output terminal of the gate drive module and the control terminals of each lower bridge arm switching transistor of the inverter.

[0007] The system includes a short-circuit protection switch module and a short-circuit protection power supply module. The short-circuit protection power supply module is powered by the battery and converted to a voltage that matches the voltage of each lower bridge arm switch. The short-circuit protection switch module is connected in series between the short-circuit protection power supply module and the control terminals of each lower bridge arm switch. When the voltage of the battery exceeds a set threshold, the short-circuit protection switch module turns on, controlling each lower bridge arm switch to turn on, so that each stator winding of the motor is coupled.

[0008] The PWM output switch module and the short-circuit protection switch module are not turned on at the same time.

[0009] Optionally, the motor is a three-phase motor, and the inverter includes a first lower bridge arm switch, a second lower bridge arm switch, and a third lower bridge arm switch.

[0010] The PWM output switch module includes a first PWM output switch, a second PWM output switch, and a third PWM output switch; the first PWM output switch is connected in series between the first lower bridge arm control output terminal of the gate drive module and the control terminal of the first lower bridge arm switch; the second PWM output switch is connected in series between the second lower bridge arm control output terminal of the gate drive module and the control terminal of the second lower bridge arm switch; the third PWM output switch is connected in series between the third lower bridge arm control output terminal of the gate drive module and the control terminal of the third lower bridge arm switch.

[0011] And / or, the short-circuit protection switch module includes a first short-circuit protection switch, a second short-circuit protection switch, and a third short-circuit protection switch; 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 arm switch; 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 arm switch; 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 lower bridge arm switch.

[0012] Optionally, the automotive active short-circuit protection circuit also includes:

[0013] A short-circuit protection enable module, which outputs a PWM output disabling signal and a short-circuit switch enable signal based on a short-circuit enable signal;

[0014] A PWM output disable module is connected between the short-circuit protection enable module and the PWM output switch module; the PWM output disable module is used to generate a control signal to control the PWM output switch module to disconnect based on the PWM output disable signal;

[0015] A short-circuit protection output enable module is connected between the short-circuit protection enable module and the short-circuit protection switch module; the short-circuit protection output enable module is used to generate a control signal to control the short-circuit protection switch module to turn on based on the short-circuit switch enable signal.

[0016] Optionally, the automotive active short-circuit protection circuit also includes:

[0017] A voltage acquisition module is coupled to the battery; the voltage acquisition module is used to acquire the positive voltage of the battery.

[0018] The main control module is connected between the voltage acquisition module and the short-circuit protection enable module; the main control module is used to output the short-circuit enable signal when the acquired positive voltage exceeds the set threshold.

[0019] Optionally, the automotive active short-circuit protection circuit also includes:

[0020] The circuit status monitoring module is coupled to the short-circuit protection enable module and the PWM output disable module; the circuit status monitoring module is used to monitor the working status of the short-circuit protection enable module and the PWM output disable module, and to provide feedback to the main control module.

[0021] Optionally, the output terminal of the gate drive module is directly coupled to each upper arm switch of the inverter;

[0022] The PWM output disabling module is also coupled to the gate drive module and is used to control the upper bridge arm switches to disconnect according to the PWM output disabling signal.

[0023] Optionally, the automotive active short-circuit protection circuit also includes:

[0024] A phase output status monitoring module is coupled to the stator winding of the motor; the phase output status monitoring module is used to monitor the stator winding voltage of the motor and provide feedback to the main control module.

[0025] According to another aspect of the present invention, an EMB system is provided, comprising: a main circuit and an active short-circuit protection circuit for vehicles as described in any embodiment of the present invention.

[0026] According to another aspect of the present invention, an EPS system is provided, comprising: a main circuit and an active short-circuit protection circuit for vehicles as described in any embodiment of the present invention.

[0027] According to another aspect of the present invention, a vehicle active short-circuit protection method is provided, applied to a vehicle active short-circuit protection circuit as described in any embodiment of the present invention; the vehicle active short-circuit protection method includes:

[0028] Obtain the positive terminal voltage of the battery;

[0029] If the positive voltage of the battery exceeds a set threshold, the upper bridge arm switches of the inverter are controlled to disconnect and the lower bridge arm switches of the inverter are controlled to turn on, so that the stator windings of the motor are coupled.

[0030] The technical solution provided in this invention, by setting a PWM output switch module and a short-circuit protection switch module, allows for the disconnection of the gate drive module from each lower bridge arm switch in the inverter when a line fault occurs. The PWM output switch module disconnects the gate drive module from each lower bridge arm switch, and the short-circuit protection switch module activates, supplying voltage from the short-circuit protection power supply module to each lower bridge arm switch, thereby turning them on and short-circuiting the stator windings of the motor, thus isolating the fault. The PWM output switch module physically disconnects the gate drive module from each lower bridge arm switch. Even if the output signal of the gate drive module fails, the short-circuit protection switch module and the short-circuit protection power supply module can still activate the lower bridge arm switches, achieving active short-circuit protection. This configuration provides a higher level of safety, ensuring that faults in the line can be effectively isolated.

[0031] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a block diagram of an active short-circuit protection circuit for vehicles according to an embodiment of the present invention;

[0034] Figure 2 This is a block diagram of another active short-circuit protection circuit for vehicles provided according to an embodiment of the present invention;

[0035] Figure 3 This is a module diagram of another vehicle active short-circuit protection circuit provided according to an embodiment of the present invention;

[0036] Figure 4 This is a module diagram of another vehicle active short-circuit protection circuit provided according to an embodiment of the present invention;

[0037] Figure 5 This is a flowchart of an active short-circuit protection method for vehicles provided according to an embodiment of the present invention. Detailed Implementation

[0038] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0039] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0040] This invention provides an active short-circuit protection circuit for vehicles, applied to a main circuit comprising a battery 1, an inverter 2, a gate drive module 3 for driving the inverter 2, and a motor 7. Figure 1 This is a block diagram of an active short-circuit protection circuit for vehicles provided in an embodiment of the present invention. (Reference) Figure 1 The vehicle-mounted active short-circuit protection circuit includes: a PWM output switch module 4, a short-circuit protection switch module 5, and a short-circuit protection power supply module 6. The PWM output switch module 4 is connected in series between the output terminal of the gate drive module 3 and the control terminals of each lower bridge arm switch transistor of the inverter 2. The short-circuit protection power supply module 6 is powered by the battery 1 and converted to a voltage matching each lower bridge arm switch transistor. The short-circuit protection switch module 5 is connected in series between the short-circuit protection power supply module 6 and the control terminals of each lower bridge arm switch transistor. The short-circuit protection switch module 5 conducts when the voltage of the battery 1 exceeds a set threshold, controlling the conduction of each lower bridge arm switch transistor to couple the stator windings of the motor 2. The PWM output switch module 4 and the short-circuit protection switch module 5 do not conduct simultaneously.

[0041] In this system, when motor 7 is running, battery 1 supplies power to motor 7 via inverter 2. When a power supply line fault occurs, for example, if battery 1 fails or the back EMF of motor 7 exceeds the maximum breakdown voltage that the switching transistor can withstand, the switching transistor in inverter 2 may break down due to the fault voltage, exacerbating the fault. To prevent further escalation of the fault, gate drive module 3 can control the switching transistor connected to it to turn off. However, if the switching transistor breaks down in this case, the fault current or fault voltage can still form a loop. Furthermore, direct control via gate drive module 3 may result in ineffective control of the switching transistor due to control signal failure. Therefore, further adjustment of the switching transistor in inverter 2 is necessary.

[0042] Specifically, to ensure the safe operation of each switching transistor and prevent it from being damaged by fault voltage, the PWM output switch module 4 can be disconnected, thereby cutting off the connection between the gate drive module 3 and each lower bridge arm switching transistor of the inverter 2, and thus cutting off the control of the lower bridge arm switching transistor by the gate drive module 3. Simultaneously, the short-circuit protection switch module 5 is turned on, and the voltage converted by the short-circuit protection power supply module 6 can be directly input to the control terminal of each lower bridge arm switching transistor through the short-circuit protection switch module 5. For example, the voltage of battery 1 can be 12V, and the short-circuit protection power supply module 6 can convert the 12V voltage of battery 1 to a fixed voltage of 11.5V. Each lower bridge arm switching transistor is turned on due to receiving the voltage output from the short-circuit protection power supply module 6. At this time, the stator windings of motor 7 are short-circuited to each other, which is equivalent to cutting off the circuit between battery 1 and motor 7, thereby preventing further aggravation of the fault, ensuring that each switching transistor in inverter 2 does not bear excessively high voltage, and achieving protection for each switching transistor in inverter 2.

[0043] The technical solution provided in this embodiment of the invention, by setting up a PWM output switch module 4 and a short-circuit protection switch module 5, allows the PWM output switch module 4 to disconnect the gate drive module 3 from each lower bridge arm switch in the inverter 2 when a line fault occurs. Furthermore, by turning on the short-circuit protection switch module 5, the voltage from the short-circuit protection power supply module 6 is input to each lower bridge arm switch, thereby turning on the lower bridge arm switches and short-circuiting the stator windings of the motor 7, thus achieving fault isolation. The PWM output switch module 4 can physically disconnect the connection between the gate drive module 3 and each lower bridge arm switch. Even if the output signal of the gate drive module 3 fails, the short-circuit protection switch module 5 and the short-circuit protection power supply module 6 can still turn on the lower bridge arm switches, thereby achieving active short-circuit protection. This setup provides a higher level of safety, allowing faults in the line to be effectively isolated.

[0044] Figure 2 This is a block diagram of another automotive active short-circuit protection circuit provided in an embodiment of the present invention, with reference to... Figure 2Based on the above embodiments, optionally, the motor 7 is a three-phase motor, and the inverter 2 includes a first lower arm switch Q1, a second lower arm switch Q2, and a third lower arm switch Q3. The PWM output switch module 4 includes a first PWM output switch 41, a second PWM output switch 42, and a third PWM output switch 43; the first PWM output switch 41 is connected in series between the first lower arm control output terminal of the gate drive module 3 and the control terminal of the first lower arm switch Q1; the second PWM output switch 42 is connected in series between the second lower arm control output terminal of the gate drive module 3 and the control terminal of the second lower arm switch Q2; the third PWM output switch 43 is connected in series between the third lower arm control output terminal of the gate drive module 3 and the control terminal of the third lower arm switch Q3. And / or, the short-circuit protection switch module includes a first short-circuit protection switch 51, a second short-circuit protection switch 52, and a third short-circuit protection switch 53; the first short-circuit protection switch 51 is connected in series between the short-circuit protection power supply module 6 and the control terminal of the first lower bridge arm switch Q1; the second short-circuit protection switch 52 is connected in series between the short-circuit protection power supply module 6 and the control terminal of the second lower bridge arm switch Q2; and the third short-circuit protection switch 53 is connected in series between the short-circuit protection power supply module 6 and the control terminal of the third lower bridge arm switch Q3.

[0045] When an overvoltage fault occurs in the line, the first PWM output switch 41, the second PWM output switch 42, and the third PWM output switch 43 are instantly turned off, thereby cutting off the connection between the gate drive module 3 and each lower bridge arm switch in the inverter 2. At the same time, the first short-circuit protection switch 51, the second short-circuit protection switch 52, and the third short-circuit protection switch 53 are turned on. The voltage in the short-circuit protection power supply module 6 is input to the first lower bridge arm switch Q1, the second lower bridge arm switch Q2, and the third lower bridge arm switch Q3 respectively through the first short-circuit protection switch 51, the second short-circuit protection switch 52, and the third short-circuit protection switch 53. A voltage difference is formed between the gate and source of each switch, causing the first lower bridge arm switch Q1, the second lower bridge arm switch Q2, and the third lower bridge arm switch Q3 to be turned on, thereby short-circuiting the stator winding of the motor 7, thus realizing active short-circuit protection. Moreover, each switch will not be broken down due to being subjected to high voltage, which has a high degree of safety.

[0046] Figure 3 A module diagram of another automotive active short-circuit protection circuit provided in an embodiment of the present invention is shown below. Figure 3Based on the above embodiments, optionally, the vehicle active short-circuit protection circuit further includes: a short-circuit protection enable module 8, a PWM output disable module 9, and a short-circuit protection output enable module 10. The short-circuit protection enable module 8 outputs a PWM output disable signal and a short-circuit switch enable signal according to the short-circuit enable signal; the PWM output disable module 9 is connected between the short-circuit protection enable module 8 and the PWM output switch module 4; the PWM output disable module 9 is used to generate a control signal to control the PWM output switch module 4 to disconnect according to the PWM output disable signal; the short-circuit protection output enable module 10 is connected between the short-circuit protection enable module 8 and the short-circuit protection switch module 5; the short-circuit protection output enable module 10 is used to generate a control signal to control the short-circuit protection switch module 5 to conduct according to the short-circuit switch enable signal.

[0047] Optionally, the output of the gate drive module 3 is directly coupled to each upper arm switch of the inverter 2. The PWM output disabling module 9 is also coupled to the gate drive module 3 and is used to control the upper arm switches to disconnect according to the PWM output disabling signal.

[0048] The upper arm switch can include a first upper arm switch Q4, a second upper arm switch Q5, and a third upper arm switch Q6. When the battery 1 and the motor 7 are operating normally and there is no fault in the circuit, the gate drive module 3 can control the upper and lower arm switches of the inverter 2 to invert the DC power output from the battery 1 into AC power and input it into the motor 7.

[0049] When a fault such as overvoltage occurs in the line, the short-circuit protection enable module 8 can receive a short-circuit enable signal and generate a PWM output disable signal and a short-circuit switch enable signal based on the signal. The PWM output disable signal is received by the PWM output disable module 9, which can control the first PWM output switch 41, the second PWM output switch 42, and the third PWM output switch 43 to open based on the signal, thereby cutting off the connection between the gate drive module 3 and each lower bridge arm switch in the inverter 2. The PWM output disable module 9 can also input the signal to the gate drive module 3, which can then control the first upper bridge arm switch Q4, the second upper bridge arm switch Q5, and the third upper bridge arm switch Q6 to open.

[0050] The short-circuit switch enable signal is received by the short-circuit protection output enable module 10. The short-circuit protection output enable module 10 can control the first short-circuit protection switch 51, the second short-circuit protection switch 52, and the third short-circuit protection switch 53 to be turned on according to the signal. This causes the voltage in the short-circuit protection power supply module 6 to be input to the first lower bridge arm switch Q1, the second lower bridge arm switch Q2, and the third lower bridge arm switch Q3 respectively through the first short-circuit protection switch 51, the second lower bridge arm switch Q2, and the third lower bridge arm switch Q3, thereby turning on the first lower bridge arm switch Q1, the second lower bridge arm switch Q2, and the third lower bridge arm switch Q3, realizing the mutual short-circuiting between the various stator windings of the motor 7, thus realizing active short-circuit protection.

[0051] Figure 4 A module diagram of another automotive active short-circuit protection circuit provided in an embodiment of the present invention is shown below. Figure 4 Based on the above embodiments, optionally, the vehicle active short-circuit protection circuit further includes: a voltage acquisition module 11 and a main control module 12. The voltage acquisition module 11 is coupled to the battery 1; the voltage acquisition module 11 is used to acquire the positive voltage of the battery 1; the main control module 12 is connected between the voltage acquisition module 11 and the short-circuit protection enable module 8; the main control module 12 is used to output a short-circuit enable signal when the acquired positive voltage exceeds a set threshold.

[0052] Among them, the voltage acquisition module 11 can be used to detect the voltage at the output terminal of the battery 1 and input it into the main control module 12. When the positive voltage value exceeds the set threshold, the main control module 12 can generate a short circuit enable signal and input it into the short circuit protection enable module 8, thereby controlling the active short circuit protection between the stator windings of the motor 7.

[0053] Continue to refer to Figure 4 Based on the above embodiments, the vehicle active short-circuit protection circuit may optionally include: a circuit status monitoring module 13, which is coupled to the short-circuit protection enabling module 8 and the PWM output disabling module 9; the circuit status monitoring module 13 is used to monitor the working status of the short-circuit protection enabling module 8 and the PWM output disabling module 9, and to provide feedback to the main control module 12.

[0054] When the short-circuit protection enable module 8 and the PWM output disable module 9 output signals, they also simultaneously output a feedback signal to the circuit status monitoring module 13. This feedback signal indicates whether the PWM output disable signal and the short-circuit switch enable signal of the short-circuit protection enable module 8 are effectively output, and whether the PWM output disable module 9 generates and effectively outputs the control signal that controls the PWM output switch module 4 to disconnect based on the PWM output disable signal. The circuit status monitoring module 13 can feed this feedback signal back to the main control module 12. When the short-circuit protection enable module 8 or the PWM output disable module 9 fails to output a valid signal, the main control module 12 can regenerate the short-circuit enable signal and re-input it into the short-circuit protection enable module 8 to generate the PWM output disable signal and the short-circuit switch enable signal, thus ensuring the effective operation of the active short-circuit protection.

[0055] Continue to refer to Figure 4 Based on the above embodiments, the vehicle active short-circuit protection circuit may optionally include: a phase output status monitoring module 14, which is coupled to the stator winding of the motor 7; the phase output status monitoring module 14 is used to monitor the stator winding voltage of the motor 7 and provide feedback to the main control module 12.

[0056] The phase output status monitoring module 14 can verify whether the active short circuit between the stator windings of the motor 7 is complete by detecting the stator winding voltage of the motor 7. For example, when the inverter 2 converts the DC power output from the battery 1 into three-phase AC power (A, B, C), the stator windings of the motor 7 are powered by the three-phase AC power (A, B, C) in the circuit, and the phase output status monitoring module 14 can monitor the A-phase voltage U. A Phase B voltage U B and C-phase voltage U C And input into the main control module 12, when U A =0, U B =0 and U C When the value is 0, it means that the stator winding of motor 7 has been successfully short-circuited.

[0057] This invention also provides an EMB system. The system includes a main circuit and an active short-circuit protection circuit for vehicles as provided in any embodiment of this invention. It possesses the corresponding functional modules and beneficial effects of an active short-circuit protection circuit for vehicles, which will not be elaborated further.

[0058] Among them, the EMB system (Electromechanical Brake System) is an electronic braking system that uses an electronic control unit to control the braking actuator, replacing the traditional hydraulic or pneumatic braking system. The EMB system has advantages such as rapid response, high control precision, easy integration into the vehicle's electronic system, and space saving.

[0059] This invention also provides an EPS system. The system includes a main circuit and an active short-circuit protection circuit for vehicles as provided in any embodiment of this invention. It possesses the corresponding functional modules and beneficial effects of an active short-circuit protection circuit for vehicles, which will not be elaborated further.

[0060] EPS (Electric Power Steering) is a power steering system that directly relies on an electric motor to provide auxiliary torque. It can adjust the amount of assistance in real time based on parameters such as vehicle speed and steering angle, making steering easier and more flexible, while also improving vehicle handling stability and safety. EPS systems offer advantages such as energy efficiency, environmental friendliness, compact structure, and reliable performance.

[0061] This invention also provides a method for active short-circuit protection in vehicles. Figure 5 This is a flowchart illustrating an active short-circuit protection method for vehicles provided in an embodiment of the present invention. (Reference) Figure 5 This method can be executed by the main control module and applied to the vehicle active short-circuit protection circuit provided in any embodiment of the present invention. It possesses the corresponding functional modules and beneficial effects of the vehicle active short-circuit protection circuit. The vehicle active short-circuit protection method includes:

[0062] S110, Obtain the positive voltage of the battery.

[0063] S120. If the positive voltage of the battery exceeds the set threshold, the upper bridge arm switching transistors of the inverter are disconnected and the lower bridge arm switching transistors of the inverter are turned on, so that the stator windings of the motor are coupled.

[0064] When the positive voltage of the battery exceeds the set threshold, an overvoltage fault may have occurred in the circuit. The gate drive module can control the upper arm switches of the inverter to disconnect. The short-circuit current protection module can also input a set voltage to the lower arm switches of the inverter through the short-circuit protection switch module to turn on the lower arm switches of the inverter, so that the stator windings of the motor can be coupled.

[0065] The technical solution provided by this invention achieves fault isolation by independently controlling each upper and lower bridge arm switch of the inverter and short-circuiting the stator windings of the motor. Even if the output signal of the gate drive module fails, the lower bridge arm switch can be turned on by the short-circuit protection switch module and the short-circuit protection power supply module, thereby achieving active short-circuit protection, which has a higher level of safety and allows faults in the line to be effectively isolated.

[0066] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0067] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An active short-circuit protection circuit for vehicles, characterized in that, It is applied to the main circuit that includes a battery, an inverter, a gate drive module for driving the inverter, and a motor; The vehicle active short-circuit protection circuit includes: A PWM output switching module is connected in series between the output terminal of the gate drive module and the control terminals of each lower bridge arm switching transistor of the inverter. The system includes a short-circuit protection switch module and a short-circuit protection power supply module. The short-circuit protection power supply module is powered by the battery and converted to a voltage that matches the voltage of each lower bridge arm switch. The short-circuit protection switch module is connected in series between the short-circuit protection power supply module and the control terminals of each lower bridge arm switch. When the voltage of the battery exceeds a set threshold, the short-circuit protection switch module turns on, controlling each lower bridge arm switch to turn on, so that each stator winding of the motor is coupled. The PWM output switch module and the short-circuit protection switch module are not turned on at the same time.

2. The vehicle active short-circuit protection circuit according to claim 1, characterized in that, The motor is a three-phase motor, and the inverter includes a first lower bridge arm switch, a second lower bridge arm switch, and a third lower bridge arm switch. The PWM output switch module includes a first PWM output switch, a second PWM output switch, and a third PWM output switch; the first PWM output switch is connected in series between the first lower bridge arm control output terminal of the gate drive module and the control terminal of the first lower bridge arm switch; the second PWM output switch is connected in series between the second lower bridge arm control output terminal of the gate drive module and the control terminal of the second lower bridge arm switch; the third PWM output switch is connected in series between the third lower bridge arm control output terminal of the gate drive module and the control terminal of the third lower bridge arm switch. And / or, the short-circuit protection switch module includes a first short-circuit protection switch, a second short-circuit protection switch, and a third short-circuit protection switch; 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 arm switch; 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 arm switch; 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 lower bridge arm switch.

3. The vehicle active short-circuit protection circuit according to claim 1, characterized in that, Also includes: A short-circuit protection enable module, which outputs a PWM output disabling signal and a short-circuit switch enable signal based on a short-circuit enable signal; A PWM output disable module is connected between the short-circuit protection enable module and the PWM output switch module; the PWM output disable module is used to generate a control signal to control the PWM output switch module to disconnect based on the PWM output disable signal; A short-circuit protection output enable module is connected between the short-circuit protection enable module and the short-circuit protection switch module; the short-circuit protection output enable module is used to generate a control signal to control the short-circuit protection switch module to turn on based on the short-circuit switch enable signal.

4. The vehicle active short-circuit protection circuit according to claim 3, characterized in that, Also includes: A voltage acquisition module is coupled to the battery; the voltage acquisition module is used to acquire the positive voltage of the battery. The main control module is connected between the voltage acquisition module and the short-circuit protection enable module; the main control module is used to output the short-circuit enable signal when the acquired positive voltage exceeds the set threshold.

5. The vehicle active short-circuit protection circuit according to claim 3, characterized in that, Also includes: The circuit status monitoring module is coupled to the short-circuit protection enable module and the PWM output disable module; the circuit status monitoring module is used to monitor the working status of the short-circuit protection enable module and the PWM output disable module, and to provide feedback to the main control module.

6. The vehicle active short-circuit protection circuit according to claim 1, characterized in that, The output terminal of the gate drive module is directly coupled to each upper bridge arm switch of the inverter. The PWM output disabling module is also coupled to the gate drive module and is used to control the upper bridge arm switches to disconnect according to the PWM output disabling signal.

7. The vehicle active short-circuit protection circuit according to claim 1, characterized in that, Also includes: A phase output status monitoring module is coupled to the stator winding of the motor; the phase output status monitoring module is used to monitor the stator winding voltage of the motor and provide feedback to the main control module.

8. An EMB system, characterized in that, include: The main circuit and the vehicle active short-circuit protection circuit as described in any one of claims 1-7.

9. An EPS system, characterized in that, include: The main circuit and the vehicle active short-circuit protection circuit as described in any one of claims 1-7.

10. A method for active short-circuit protection in vehicles, characterized in that, Applied to the automotive active short-circuit protection circuit as described in any one of claims 1-7; The vehicle active short-circuit protection method includes: Obtain the positive terminal voltage of the battery; If the positive voltage of the battery exceeds a set threshold, the upper bridge arm switches of the inverter are controlled to disconnect and the lower bridge arm switches of the inverter are controlled to turn on, so that the stator windings of the motor are coupled.

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