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

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 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 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 the individual lower bridge branch switching transistors; wherein the short-circuit protection switching 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 an effective elimination of faults in the line.

Description

AREA OF INVENTION

[0001] 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

[0002] 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.

[0003] 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

[0004] 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.

[0005] 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.

[0006] 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 the control terminal of the third lower bridge branch switching transistor.

[0007] 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 signal; a PWM output disabling module that is connected between the short-circuit protection enabling module and the PWM output switching module; wherein the PWM output deactivation module serves to generate a control signal according to the PWM output deactivation signal, which switches off the PWM output switching module; a short-circuit protection output activation module connected between the short-circuit protection activation module and the short-circuit protection switching module; wherein the short-circuit protection output activation module serves to generate a control signal according to the short-circuit switch activation signal, which switches on the short-circuit protection switching module.

[0008] Optionally, the active short-circuit protection circuit for vehicles also includes: a voltage sensing module coupled to the battery; wherein the voltage sensing module serves to detect the positive terminal voltage of the battery; a main control module connected between the voltage sensing module and the short-circuit protection activation module; wherein the main control module serves to output the short-circuit activation signal when the detected positive terminal voltage exceeds the specified threshold.

[0009] Optionally, the active short-circuit protection circuit for vehicles also includes: a circuit state monitoring module coupled to the short-circuit protection activation module and the PWM output deactivation module; wherein the circuit state monitoring module serves to to monitor the operating status of the short-circuit protection activation module and the PWM output deactivation module and report it back to the main control module.

[0010] Optionally, the output terminal of the gate driver module is directly coupled to the individual upper bridge branch switching transistors of the inverter; where the PWM output deactivation module is also coupled to the gate driver module and serves to switch off the upper bridge branch switching transistors according to the PWM output deactivation signal.

[0011] Optionally, the active short-circuit protection circuit for vehicles also includes: a phase output state monitoring module coupled to the stator windings of the motor; wherein the phase output- The condition monitoring module serves to monitor the voltage at the stator windings. to monitor the engine and report back to the main control module.

[0012] 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 according to any embodiment of the present invention.

[0013] According to another aspect of the present invention, an EPS system is provided which comprises: a main circuit and an active short-circuit protection circuit for vehicles according to any embodiment of the present invention.

[0014] According to a further aspect of the present invention, an active short-circuit protection method for vehicles is provided, which is applied to the active short-circuit protection circuit for vehicles according to any embodiment of the present invention; wherein the active short-circuit protection method for vehicles comprises: Measuring the positive terminal voltage of the battery; When the positive terminal voltage of the battery exceeds a defined threshold, the individual upper bridge branch switching transistors of the inverter are switched off and the individual lower bridge branch switching transistors of the inverter are switched on, so that the individual stator windings of the motor are coupled.

[0015] The technical solution provided in the exemplary embodiment of the present invention can, by activating a PWM output switching module and a short-circuit protection switching module, interrupt the connection between the gate driver module and the individual lower bridge branch switching transistors of the inverter by means of the PWM output switching module when a line fault occurs, and by activating the short-circuit protection switching module, inject the voltage of the short-circuit protection power supply module into the lower bridge branch switching transistors, thereby switching them on and short-circuiting the stator windings of the motor, thus effectively eliminating the fault. The PWM output switching module can physically interrupt the connection between the gate driver module and the individual lower bridge branch switching transistors.Even if the output signal of the gate driver module fails, the individual lower bridge branch switching transistors can be turned on by the short-circuit protection switching module and the short-circuit protection power supply module, thus providing active short-circuit protection. This configuration offers a higher level of safety, so that faults in the line can be effectively switched off.

[0016] It is understood that the content described in this section is neither intended to identify key or important features of the embodiments of the present invention, nor to limit the scope of the present invention. Further features of the present invention will be readily understood from the following description. DESCRIPTION OF THE FIGURES

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the figures necessary for describing these embodiments are briefly presented below. It is obvious that the figures described below represent only a few embodiments of the present invention. Individuals skilled in the art in this field can create further figures based on these figures without inventive step. Fig. 1 is a module diagram of an active short-circuit protection circuit for vehicles, provided by an embodiment of the present invention; Fig. 2 is a module diagram of another active short-circuit protection circuit for vehicles, which is provided by an embodiment of the present invention; Fig. 3 is a module diagram of a further active short-circuit protection circuit for vehicles, which is provided by an embodiment of the present invention; Fig. 4 is a module diagram of a further active short-circuit protection circuit for vehicles, which is provided by an embodiment of the present invention; Fig. Figure 5 is a flowchart of an active short-circuit protection method for vehicles, which is provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EXECUTION FORMS

[0018] To enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention are described clearly and completely below with reference to the figures. It is understood that the described embodiments represent only a subset of the embodiments of the present invention and not all of them. Based on the embodiments of the present invention, all other embodiments that could be devised by a person skilled in the art without inventive step should fall within the scope of protection of the present invention.

[0019] It should be noted that the terms "first," "second," etc., are used in the description and claims of the present invention and in the figures mentioned above to distinguish similar objects and do not necessarily serve to define a particular order or sequence. It is understood that the data used in this way are interchangeable under suitable circumstances, so that the embodiments of the invention described herein may also be carried out in a different order than that shown or described here. Furthermore, the terms "comprise" and "feature," and all variations thereof, are intended to cover non-exclusive inclusion.For example, a process, procedure, system, product or device comprising a series of steps or units is not necessarily limited to the steps or units expressly listed, but may include further steps or units that are not expressly listed or are inherent in such a process, procedure, product or device.

[0020] One embodiment of the present invention provides an active short-circuit protection circuit for vehicles, which is applied to a main circuit comprising a battery 1, an inverter 2, a gate driver module 3 for driving the inverter 2 and a motor 7. Fig. Figure 1 is a module diagram of an active short-circuit protection circuit for vehicles, provided by an embodiment of the present invention. With reference to Fig. 1 comprises the active short-circuit protection circuit for vehicles: a PWM output switching module 4, a short-circuit protection switching module 5 and a short-circuit protection power supply module 6. The PWM output switching module 4 is connected in series between the output terminal of the gate driver module 3 and the control terminals of the individual lower bridge branch switching transistors of the inverter 2.The short-circuit protection power supply module 6 is powered by battery 1 and generates a voltage suitable for the lower bridge branch switching transistors; the short-circuit protection switching module 5 is connected in series between the short-circuit protection power supply module 6 and the control terminals of the individual lower bridge branch switching transistors; the short-circuit protection switching module 5 switches on when the voltage of battery 1 exceeds a defined threshold and controls the switching on of the lower bridge branch switching transistors, thus coupling the individual stator windings of motor 2. The PWM output switching module 4 and the short-circuit protection switching module 5 do not switch on simultaneously.

[0021] When motor 7 is running, battery 1 supplies power to motor 7 via inverter 2. If a fault occurs in the power supply line, for example, a defect in battery 1 or a counter-electromotive force from motor 7 exceeding the maximum breakdown voltage of the switching transistors, the switching transistors in inverter 2 can fail due to the fault voltage, thus exacerbating the fault. To prevent further escalation of the fault, gate driver module 3 can switch off the switching transistors connected to it. However, in this case, a circuit for the fault current or fault voltage can still be completed via the failed switching transistors. Furthermore, a failure of the control signal could render the switching transistors ineffective by the direct control method using gate driver module 3.Therefore, the switching transistors in inverter 2 should be further controlled.

[0022] More precisely, the PWM output switching module 4 can be disconnected to ensure the safe operation of the individual switching transistors and to prevent breakdown due to a fault voltage. This interrupts the connection between the gate driver module 3 and the individual lower bridge branch switching transistors of the inverter 2, thus terminating the control of the gate driver module 3 via the lower bridge branch switching transistors. Simultaneously, the short-circuit protection switching module 5 is switched on, and the voltage converted by the short-circuit protection power supply module 6 can be directly fed into the control terminals of the lower switching transistors via the short-circuit protection switching module 5. For example, if the voltage of battery 1 is 12 V, the short-circuit protection power supply module 6 can convert the 12 V voltage of battery 1 into a constant voltage of 11.5 V.The lower bridge branch switching transistors are switched on by the voltage output from the short-circuit protection power supply module 6. This short-circuits the stator windings of the motor 7, which is equivalent to an interruption of the circuit between the battery 1 and the motor 7, thus preventing further escalation of the fault and ensuring that the switching transistors in the inverter 2 are not subjected to overvoltage, thereby guaranteeing the protection of the switching transistors in the inverter 2.

[0023] The technical solution provided in the exemplary embodiment of the present invention can, by switching on a PWM output switching module 4 and a short-circuit protection switching module 5, interrupt the connection between the gate driver module 3 and the individual lower bridge branch switching transistors of the inverter 2 by means of the PWM output switching module 4 when a line fault occurs, and by switching on the short-circuit protection switching module 5, inject the voltage of the short-circuit protection power supply module 6 into the lower bridge branch switching transistors and thereby switch on the lower bridge branch switching transistors, so that the stator windings of the motor 7 are short-circuited, thus effectively eliminating the fault. The PWM output switching module 4 can physically interrupt the connection between the gate driver module 3 and the individual lower bridge branch switching transistors.Even if the output signal of the gate driver module 3 fails, the individual lower bridge branch switching transistors can be switched on by the short-circuit protection switching module 5 and the short-circuit protection power supply module 6, thus providing active short-circuit protection. This configuration offers a higher level of safety, so that faults in the line can be effectively switched off.

[0024] Fig. 2 is a module diagram of another active short-circuit protection circuit for vehicles, which is provided by an embodiment of the present invention. With reference to Fig. 2 and, based on the above embodiments, optionally the motor 7 is a three-phase motor and the inverter 2 comprises a first lower switching transistor Q1, a second lower switching transistor Q2, and a third lower switching transistor Q3. The PWM output switching module 4 comprises a first PWM output switch 41, a second PWM output switch 42, and a third PWM output switch 43; wherein the first PWM output switch 41 is connected in series between the control output terminal of the first lower bridge branch of the gate driver module 3 and the control terminal of the first lower bridge branch switching transistor Q1; wherein the second PWM output switch 42 is connected in series between the control output terminal of the second lower bridge branch of the gate driver module 3 and the control terminal of the second lower bridge branch switching transistor Q2; wherein the third PWM output switch 43 is connected in series between the control output terminal of the third lower bridge branch of the gate driver module 3 and the control terminal of the third lower bridge branch switching transistor Q3.

[0025] And / or the short-circuit protection switching module comprises a first short-circuit protection switch 51, a second short-circuit protection switch 52, and a third short-circuit protection switch 53; wherein 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 branch switching transistor Q1; wherein 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 branch switching transistor Q2; wherein 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 branch switching transistor Q3.

[0026] If a fault such as an overvoltage occurs in the line, the first PWM output switch 41, the second PWM output switch 42, and the third PWM output switch 43 are immediately switched off, thus interrupting the connection between the gate driver module 3 and the individual lower bridge branch switching transistors in the inverter 2. Simultaneously, the first short-circuit protection switch 51, the second short-circuit protection switch 52, and the third short-circuit protection switch 53 are switched on, and the voltage in the short-circuit protection power supply module 6 is applied via the first short-circuit protection switch 51, the second short-circuit protection switch 52, and the third short-circuit protection switch 53, respectively, to the first lower bridge branch switching transistor Q1, the second lower bridge branch switching transistor Q2, and the third lower bridge branch switching transistor Q3.A voltage difference is created between the gate and the source of each switching transistor, causing the first lower bridge branch switching transistor Q1, the second lower bridge branch switching transistor Q2, and the third lower bridge branch switching transistor Q3 to all be switched on, thus short-circuiting the stator windings of motor 7, thereby implementing active short-circuit protection and preventing the switching transistors from being exposed to high voltages that could lead to breakdown, thus ensuring a high level of safety.

[0027] Fig. Figure 3 is a module diagram of a further active short-circuit protection circuit for vehicles, which is provided by an embodiment of the present invention. With reference to Fig. 3 and based on the above embodiments, the active short-circuit protection circuit for vehicles optionally further comprises: a short-circuit protection activation module 8, a PWM output deactivation module 9 and a short-circuit protection output activation module 10.The short-circuit protection activation module 8 outputs a PWM output deactivation signal and a short-circuit switch activation signal in response to a short-circuit activation signal; the PWM output deactivation module 9 is connected between the short-circuit protection activation module 8 and the PWM output switching module 4; the PWM output deactivation module 9 serves to generate a control signal in response to the PWM output deactivation signal, which switches off the PWM output switching module 4; the short-circuit protection output activation module 10 is connected between the short-circuit protection activation module 8 and the short-circuit protection switching module 5; the short-circuit protection output activation module 10 serves to generate a control signal in response to the short-circuit switch activation signal, which switches on the short-circuit protection switching module 5.

[0028] Optionally, the output terminal of the gate driver module 3 is directly coupled to the individual upper bridge branch switching transistors of the inverter 2. The PWM output deactivation module 9 is also coupled to the gate driver module 3 and serves to switch off the upper bridge branch switching transistors according to the PWM output deactivation signal.

[0029] The upper bridge branch switching transistors can comprise a first upper bridge branch switching transistor Q4, a second upper bridge branch switching transistor Q5, and a third upper bridge branch switching transistor Q6. If battery 1 and motor 7 are functioning normally and there is no fault in the line, the gate driver module 3 can convert the DC current output by battery 1 into AC current and feed it into motor 7 by controlling the upper bridge branch switching transistors and the lower bridge branch switching transistors of inverter 2.

[0030] If a fault such as an overvoltage occurs in the line, the short-circuit protection activation module 8 can receive a short-circuit activation signal and generate a PWM output deactivation signal and a short-circuit switch activation signal accordingly. The PWM output deactivation signal is received by the PWM output deactivation module 9, which can then control the first PWM output switch 41, the second PWM output switch 42, and the third PWM output switch 43 to disconnect them according to the signal, thereby interrupting the connection between the gate driver module 3 and the individual lower bridge branch switching transistors in the inverter 2.The PWM output disabling module 9 can also input the signal into the gate driver module 3, and the gate driver module 3 controls the disconnection of the first upper bridge branch switching transistor Q4, the second upper bridge branch switching transistor Q5, and the third upper bridge branch switching transistor Q6.

[0031] The short-circuit switch activation signal is received by the short-circuit protection output activation module 10.The short-circuit protection output activation module 10 can switch on the first short-circuit protection switch 51, the second short-circuit protection switch 52 and the third short-circuit protection switch 53 according to the signal, so that the voltage in the short-circuit protection power supply module 6 is applied via the first short-circuit protection switch 51, the second short-circuit protection switch 52 and the third short-circuit protection switch 53 to the first lower bridge branch switching transistor Q1, the second lower bridge branch switching transistor Q2 and the third lower bridge branch switching transistor Q3 respectively, thereby switching on the first lower bridge branch switching transistor Q1, the second lower bridge branch switching transistor Q2 and the third lower bridge branch switching transistor Q3, thus short-circuiting the stator windings of the motor 7 together and thus realizing active short-circuit protection.

[0032] Fig. 4 is a module diagram of a further active short-circuit protection circuit for vehicles, which is provided by an embodiment of the present invention. With reference to Fig. 4 and based on the above embodiments, the active short-circuit protection circuit for vehicles optionally further comprises: a voltage sensing module 11 and a main control module 12. The voltage sensing module 11 is coupled to the battery 1; wherein the voltage sensing module 11 serves to detect the positive terminal voltage of the battery 1; wherein the main control module 12 is connected between the voltage sensing module 11 and the short-circuit protection activation module 8; wherein the main control module 12 serves to output the short-circuit activation signal when the detected positive terminal voltage exceeds the specified threshold.

[0033] The voltage sensing module 11 can be used to detect the voltage at the output of battery 1 and input it into the main control module 12. If the voltage value at the positive terminal exceeds the defined threshold, the main control module 12 can generate a short-circuit activation signal and input it into the short-circuit protection activation module 8, thereby initiating active short-circuit protection between the stator windings of motor 7.

[0034] With further reference to Fig. 4 and based on the above embodiments, the active short-circuit protection circuit for vehicles optionally further comprises: a circuit state monitoring module 13, which is coupled to the short-circuit protection activation module 8 and to the PWM output deactivation module 9; wherein the circuit state monitoring module 13 serves to monitor the operating state of the short-circuit protection activation module 8 and the PWM output deactivation module 9 and to report it back to the main control module 12.

[0035] When the short-circuit protection activation module 8 and the PWM output deactivation module 9 output signals, they simultaneously send a feedback signal to the circuit state monitoring module 13. This feedback signal indicates whether the PWM output deactivation signal and the short-circuit switch activation signal of the short-circuit protection activation module 8 are effectively output, and whether the PWM output deactivation module 9 generates and effectively outputs a control signal to switch off the PWM output switching module 4 in accordance with the PWM output deactivation signal. The circuit state monitoring module 13 can then relay this feedback signal to the main control module 12.If the short-circuit protection activation module 8 or the PWM output deactivation module 9 cannot perform an effective signal output, the main control module 12 can generate a short-circuit activation signal again and input it again into the short-circuit protection activation module 8 to generate a PWM output deactivation signal and a short-circuit switch activation signal, thus ensuring the effective implementation of active short-circuit protection.

[0036] With further reference to Fig. 4 and based on the above embodiments, the active short-circuit protection circuit for vehicles optionally further comprises: a phase output condition monitoring module 14 coupled to the stator windings of the motor 7; wherein the phase output condition monitoring module 14 serves to monitor the voltage at the stator windings of the motor 7 and to report it back to the main control module 12.

[0037] The phase output condition monitoring module 14 can verify whether the active short circuit between the stator windings is complete by sensing the stator winding voltage of the motor 7. For example, when the inverter 2 converts the direct current output by the battery 1 into a three-phase alternating current with phases A, B, and C, the stator windings of the motor 7 are supplied by the three-phase alternating current with phases A, B, and C in the line, and the phase output condition monitoring module 14 can detect the A-phase voltage U. A , B-phase voltage U B and monitor the C-phase voltage Uc and input it into the main control module 12. If U A =0, U B If Uc = 0 and Uc = 0, this indicates that the stator windings of motor 7 have been successfully short-circuited.

[0038] One embodiment of the present invention further provides an EMB system. The system comprises: a main circuit and an active short-circuit protection circuit for vehicles according to any embodiment of the present invention. The corresponding functional modules and advantageous effects of the active short-circuit protection circuit for vehicles are not described further.

[0039] The EMB system (Electromechanical Brake System) is an electronic braking system that uses an electronic control unit to control the brake actuator, thus replacing the conventional hydraulic or pneumatic braking system. The EMB system offers the advantages of fast response, high control accuracy, easy integration into the vehicle's electronics system, and space savings.

[0040] One embodiment of the present invention further provides an EPS system. The system comprises: a main circuit and an active short-circuit protection circuit for vehicles according to any embodiment of the present invention. The corresponding functional modules and advantageous effects of the active short-circuit protection circuit for vehicles are not described further.

[0041] The EPS system (Electronic Power Steering) is a power steering system that relies directly on the engine to provide auxiliary torque. It can adjust the power assistance in real time to parameters such as vehicle speed and steering angle, making steering easier and more flexible while simultaneously improving vehicle stability and safety. The EPS system offers the advantages of energy savings, environmental friendliness, a compact design, and reliable performance.

[0042] One embodiment of the present invention further provides an active short-circuit protection method for vehicles. Fig. Figure 5 is a flowchart of an active short-circuit protection method for vehicles, provided by an embodiment of the present invention. With reference to Fig.5. The method can be implemented by a main control module and applied to an active short-circuit protection circuit for vehicles according to any embodiment of the present invention, and comprises corresponding functional modules and advantageous effects of the active short-circuit protection circuit for vehicles. The active short-circuit protection method for vehicles comprises: S110: Measuring the positive terminal voltage of the battery. S120: If the positive terminal voltage of the battery exceeds a specified threshold, the individual upper bridge branch switching transistors of the inverter are switched off and the individual lower bridge branch switching transistors of the inverter are switched on, so that the individual stator windings of the motor are coupled.

[0043] If the battery's positive terminal voltage exceeds the specified threshold, an overvoltage fault may be present in the line. The gate driver module can switch off the inverter's upper bridge switching transistors. The short-circuit current protection module can also apply a constant voltage to the inverter's lower bridge switching transistors via the short-circuit protection switching module to switch them on and couple the motor's stator windings.

[0044] The technical solution provided in the exemplary embodiment of the present invention achieves fault elimination by independently controlling the upper and lower bridge branch switching transistors of the inverter and by short-circuiting the stator windings of the motor. Even if the output signal of the gate driver module fails, the individual lower bridge branch switching transistors can be switched on by the short-circuit protection switching module and the short-circuit protection power supply module, thus providing active short-circuit protection. This offers a higher level of safety, so that faults in the line can be effectively eliminated.

[0045] It is understood that the various forms of the process flow described above can be used, with steps being rearranged, added, or deleted. For example, the steps described in the present invention can be carried out in parallel, sequentially, or in different orders, as long as the expected results of the technical solution of the present invention can be achieved, and no restrictions are imposed here.

[0046] The above detailed description of the embodiments does not constitute a limitation of the scope of protection of the present invention. It should be clear to those skilled in the art that, depending on design requirements and other factors, various modifications, combinations, sub-combinations, and substitutions can be made. All modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0047] 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.

[0048] In one embodiment of the active short-circuit protection circuit for vehicles, the motor is a three-phase motor and the inverter comprises 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 the control terminal of the third lower bridge branch switching transistor.

[0049] In another embodiment, the active short-circuit protection circuit for vehicles further 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 signal; a PWM output disabling module connected between the short-circuit protection enabling module and the PWM output switching module; wherein the PWM output disabling module serves to generate a control signal according to the PWM output disabling signal, which switches off the PWM output switching module; a short-circuit protection output activation module connected between the short-circuit protection activation module and the short-circuit protection switching module; wherein the short-circuit protection output activation module serves to generate a control signal according to the short-circuit switch activation signal, which switches on the short-circuit protection switching module.

[0050] In another embodiment, the active short-circuit protection circuit for vehicles further includes: a voltage sensing module coupled to the battery; wherein the voltage sensing module serves to detect the positive terminal voltage of the battery; a main control module connected between the voltage sensing module and the short-circuit protection activation module; wherein the main control module serves to output the short-circuit activation signal when the detected positive terminal voltage exceeds the specified threshold.

[0051] In another embodiment, the active short-circuit protection circuit for vehicles further includes: a circuit state monitoring module coupled to the short-circuit protection activation module and the PWM output deactivation module; wherein the circuit state monitoring module serves to monitor the operating state of the short-circuit protection activation module and the PWM output deactivation module and to report it back to the main control module.

[0052] In another embodiment, in the active short-circuit protection circuit for vehicles, the output terminal of the gate driver module is directly coupled to the individual upper bridge branch switching transistors of the inverter; where the PWM output deactivation module is also coupled to the gate driver module and serves to switch off the upper bridge branch switching transistors according to the PWM output deactivation signal.

[0053] In another embodiment, the active short-circuit protection circuit for vehicles further includes: a phase output condition monitoring module coupled to the stator windings of the motor; wherein the phase output condition monitoring module serves to monitor the voltage at the stator windings of the motor and to report it back to the main control module.

[0054] An EMB system is provided, which includes: a main circuit and one of the aforementioned active short-circuit protection circuits for vehicles.

[0055] In one embodiment, the EPS system comprises: a main circuit and one of the aforementioned active short-circuit protection circuits for vehicles.

[0056] An active short-circuit protection method for vehicles is provided, which is applied to one of the aforementioned active short-circuit protection circuits for vehicles; wherein the active short-circuit protection method for vehicles comprises: Measuring the positive terminal voltage of the battery; When the positive terminal voltage of the battery exceeds a defined threshold, the individual upper bridge branch switching transistors of the inverter are switched off and the individual lower bridge branch switching transistors of the inverter are switched on, so that the individual stator windings of the motor are coupled.

Claims

[1] Active short-circuit protection circuit for a vehicle, applied to a main circuit comprising a battery, an inverter, a gate control 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 in series 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; and 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 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 switched on when the voltage of the battery exceeds a certain threshold in order to control that each of the switching transistors of the lower bridge branch is switched on, so that stator windings of the motor are coupled; wherein The PWM output switching module and the short-circuit protection switching module cannot be switched on simultaneously. [2] 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. [3] 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 switching enable signal based on a short-circuit enable signal; a PWM output blocking module connected between the short-circuit protection activation module and the PWM output switching module, wherein the PWM output blocking module is configured to generate a control signal to control the PWM output switching module to be switched off based on the PWM output blocking signal; and a short-circuit protection output activation module that is connected between the short-circuit protection activation module and the short-circuit protection switching module, 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 switching enable signal, so that it switches on. [4] 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 that is 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. [5] 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 report it back to the main control module. [6] Active short-circuit protection circuit according to claim 1, wherein the output terminal of the gate control 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. [7] 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. [8] Active short-circuit protection circuit according to claim 1, wherein the main circuit is associated with an electromechanical braking system. [9] Active short-circuit protection circuit according to claim 1, wherein the main circuit is associated with an electronic power steering system. [10] Active short-circuit protection circuit according to claim 1, wherein the short-circuit protection switching module: a positive electrode voltage of 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. [11] 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. [12] Active short-circuit protection circuit according to claim 11, wherein the motor is associated with an electromechanical braking system. [13] Active short-circuit protection circuit according to claim 11, wherein the motor is associated with an electronic power steering system. [14] Active short-circuit protection circuit according to claim 11, further comprising a short-circuit protection activation module. [15] 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. [16] Active short-circuit protection circuit according to claim 14, further comprising a PWM output blocking module connected between the short-circuit protection activation module and the PWM output switching module. [17] Active short-circuit protection circuit according to claim 16, wherein the PWM output blocking module is configured to generate a control signal for controlling the PWM output switching module based on the PWM output blocking signal, so that it switches off. [18] Active short-circuit protection circuit according to claim 16, further comprising a short-circuit protection output activation module connected between the short-circuit protection activation module and the short-circuit protection switching module. [19] Active short-circuit protection circuit according to claim 18, wherein the short-circuit protection output activation module is configured to generate a control signal for controlling the short-circuit protection switching module based on the short-circuit switch enable signal, so that it switches on. [20] Active short-circuit protection method, including: 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; 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, a short-circuit protection switching module is activated, causing (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) stator windings of an associated motor.

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