Trailer protection method and device, electronic equipment, motor control system and vehicle

Abstract

The invention relates to a trailer protection method and device, electronic equipment, a motor control system and a vehicle, and the method comprises the steps: determining the short-circuit position of a bridge arm under the condition that the short-circuit fault of the bridge arm is detected and the vehicle is dragged; wherein the position is an upper bridge arm or a lower bridge arm; when the position where the bridge arm is short-circuited is the upper bridge arm, active short-circuit operation is executed on all the upper bridge arms, and when the position where the bridge arm is short-circuited is the lower bridge arm, active short-circuit operation is executed on all the lower bridge arms.

Description

Technical Field

[0001] The present disclosure relates to vehicle trailer technology, and more specifically, to a trailer protection method, device, electronic equipment, motor control system and vehicle. Background Art

[0002] At present, when a vehicle (such as a pure electric vehicle or a hybrid electric vehicle) fails and cannot be driven, it will be towed. When a vehicle's motor control system fails, for example, a bridge arm short circuit failure, the bridge arm short circuit failure may be caused by a power tube short circuit, an abnormal output of the main control chip PWM (Pulse-Width Modulation), a short circuit or level reversal of the PWM transmission path, or an abnormal output of the driver chip. The above faults cannot be reliably detected under low-voltage static conditions and need to be reliably detected under high voltage. However, the vehicle cannot supply high voltage to power the motor drive system at this time, and may misjudge that the vehicle can be towed. In this case, when the vehicle is towed, although the motor speed is low, it will also generate a huge short-circuit current, which may cause the motor controller to catch fire and cause a serious accident.

[0003] Therefore, it is necessary to provide a new technical solution to protect the vehicle when the vehicle is towed. Summary of the invention

[0004] An object of the present invention is to provide a new technical solution for a trailer protection method.

[0005] According to a first aspect of the present invention, there is provided a trailer protection method, comprising:

[0006] When a bridge arm short circuit fault is detected and the vehicle is towed, determining the position where the bridge arm short circuit occurs; wherein the position is the upper bridge arm or the lower bridge arm;

[0007] When the short-circuited bridge arm is located at the upper bridge arm, an active short-circuit operation is performed on all upper bridge arms; and when the short-circuited bridge arm is located at the lower bridge arm, an active short-circuit operation is performed on all lower bridge arms.

[0008] Optionally, determining the position where the short circuit occurs in the bridge arm includes:

[0009] When it is determined that a short circuit occurs in the bridge arm, all phase current values ​​are obtained;

[0010] Determine a target phase current value according to all the phase current values; wherein the target phase current value is the phase current value with the largest absolute value among all the phase current values;

[0011] When the target current value is a positive value, it is determined that the upper bridge arm is short-circuited, and when the target current value is a negative value, it is determined that the lower bridge arm is short-circuited.

[0012] Optionally, determining the position where the short circuit occurs in the bridge arm includes:

[0013] When it is determined that a short circuit occurs in a bridge arm, error information of all bridge arms is obtained;

[0014] When at least one upper bridge arm error information exists in all the bridge arm error information, it is determined that a short circuit occurs in the upper bridge arm; and when at least one lower bridge arm error information exists in all the bridge arm error information, it is determined that a short circuit occurs in the lower bridge arm.

[0015] Optionally, the method further includes:

[0016] When a bridge arm fault or an overcurrent fault is detected, all phase current values ​​and a preset current value are obtained;

[0017] When the absolute values ​​of all the phase current values ​​are greater than the preset current value, and the duration that all the phase current values ​​are greater than the preset current value exceeds a first preset time, it is determined that a short circuit fault occurs in the bridge arm.

[0018] Optionally, the method further includes:

[0019] A heat dissipation request is sent to the vehicle controller so that the vehicle controller controls the heat dissipation system to perform a heat dissipation operation.

[0020] Optionally, the method further includes:

[0021] When a bridge arm short circuit fault is detected and the vehicle is driven by a power source other than the power source where the bridge arm short circuit fault occurs, the vehicle speed is controlled to be less than a preset speed so that the actual short circuit current value is less than the rated working current value.

[0022] Optionally, the method further includes:

[0023] Obtaining a rated working current value and a pre-calibrated corresponding relationship, wherein the pre-calibrated corresponding relationship records the rated working current values ​​corresponding to different motor speeds;

[0024] According to the corresponding relationship between the rated working current value and the pre-calibrated corresponding relationship, finding a first motor speed corresponding to the rated working current value;

[0025] The motor is controlled to rotate at a speed lower than the first motor speed, so that the vehicle speed is lower than a preset vehicle speed.

[0026] Optionally, the method further includes:

[0027] Obtaining actual short-circuit current value and preset coefficient;

[0028] Determine the second motor speed according to the actual short-circuit current value, the rated operating current value, the first motor speed and the preset coefficient;

[0029] The motor is controlled to rotate at a speed lower than the second motor speed, so that the vehicle speed is lower than a preset vehicle speed.

[0030] Optionally, the method further includes:

[0031] When all power sources of the vehicle are in an inoperative state and the position sensor is operating normally, the actual speed of the motor is obtained;

[0032] When the actual motor speed exceeds the preset motor speed, and a duration during which the actual motor speed exceeds the preset motor speed exceeds a second preset time, it is determined that the vehicle is towed.

[0033] Optionally, the method further includes:

[0034] When all power sources of the vehicle are in an inoperative state and the position sensor fails, the actual wheel speed of the vehicle driving wheel is obtained;

[0035] When the actual wheel speed of the driving wheels of the vehicle exceeds the preset vehicle speed, and the duration for which the actual wheel speed of the driving wheels of the vehicle exceeds the preset vehicle speed exceeds a third preset time, it is determined that the vehicle is towed.

[0036] According to a second aspect of the present invention, there is provided a trailer protection device, comprising:

[0037] A bridge arm short circuit position determination module, used to determine the position where the bridge arm short circuit occurs when a bridge arm short circuit fault is detected and the vehicle is towed; wherein the position is the upper bridge arm or the lower bridge arm;

[0038] The active short-circuit module is used to perform an active short-circuit operation on all upper bridge arms when the short-circuit position of the bridge arm is the upper bridge arm, and to perform an active short-circuit operation on all lower bridge arms when the short-circuit position of the bridge arm is the lower bridge arm.

[0039] According to a third aspect of the present invention, there is provided an electronic device comprising a memory and a processor, wherein the memory stores a computer program for controlling the processor to operate so as to execute the trailer protection method according to any one of the first aspects of the present invention.

[0040] According to a fourth aspect of the present invention, a motor control system is provided, comprising an inverter, a motor and the trailer protection device as described in the second aspect of the present invention or the electronic device as described in the third aspect, wherein the inverter and the motor are both electrically connected to the trailer protection device or the electronic device.

[0041] According to a fifth aspect of the present invention, a vehicle is provided, comprising the motor control system as described in the fourth aspect.

[0042] The trailer protection method provided by the embodiment of the present invention determines the position where the bridge arm short-circuit occurs. When the position where the bridge arm short-circuit occurs is the upper bridge arm, an active short-circuit operation is performed on all the upper bridge arms, and when the position where the bridge arm short-circuit occurs is the lower bridge arm, an active short-circuit operation is performed on all the lower bridge arms, so that the short-circuit current of each phase is in a balanced state, avoiding damage to the motor and the motor controller caused by excessive short-circuit current of one phase, playing a protective role when the vehicle is towed in this case, ensuring safety, and at the same time, this trailer protection method has strong versatility and good reliability.

[0043] Features and advantages of the embodiments of the present specification will become apparent from the following detailed description of exemplary embodiments of the present specification with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the specification and, together with the description, serve to explain the principles of the embodiments of the specification.

[0045] Figure 1 is a processing flow chart of a trailer protection method according to an embodiment of the present invention.

[0046] Figure 2 4 is a processing flow chart of a method for determining a position where a bridge arm short circuit occurs according to an embodiment of the present invention.

[0047] Figure 3 4 is a processing flow chart of a method for detecting whether a vehicle is being towed according to an embodiment of the present invention.

[0048] Figure 4 is a processing flow chart of a trailer protection method according to an embodiment of the present invention.

[0049] Figure 5 4 is a principle block diagram of a trailer protection device according to an embodiment of the present invention.

[0050] Figure 6 Schematic diagram of the hardware structure of a trailer protection device according to an embodiment of the present invention.

[0051] Figure 7 Schematic diagram of the hardware structure of a motor control system according to an embodiment of the present invention.

[0052] Figure 8 is a functional block diagram of a vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0053] Various exemplary embodiments of the present specification will now be described in detail with reference to the accompanying drawings.

[0054] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the embodiments of the present specification and its application or uses.

[0055] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0056] In one embodiment of the present invention, a trailer protection method is provided, which is applicable to pure electric vehicles and hybrid electric vehicles, and is executed when all power sources of the vehicle are in an inoperative state.

[0057] according to Figure 1 As shown, the trailer protection method of this embodiment may include the following steps S110 to S120.

[0058] Step S110, when a bridge arm short circuit fault is detected and the vehicle is towed, determine the position where the bridge arm short circuit occurs; wherein the position is the upper bridge arm or the lower bridge arm.

[0059] An inverter usually includes multiple phase outputs, each phase consisting of an upper bridge arm and a lower bridge arm. Taking a three-phase inverter as an example, a three-phase inverter usually includes three phase outputs.

[0060] The upper bridge arm of each phase contains one or more switching elements, such as IGBT (Insulated Gate Bipolar Transistor) or MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), which is connected between the positive electrode (or high-voltage side) of the DC power supply and the output of the phase. When the switching element of the upper bridge arm is turned on, the positive electrode of the power supply is connected to the output of the phase, so that the current can flow to the motor or other load.

[0061] The lower arm of each phase contains one or more switching elements, such as IGBTs or MOSFETs, connected between the negative pole (or low-voltage side) of the DC power supply and the output of the phase. When the switching element of the lower arm is turned on, the negative pole of the power supply is connected to the output of the phase, allowing current to flow back to the power supply from the motor or other load.

[0062] Step S120, when the short-circuited bridge arm is located at the upper bridge arm, an active short-circuit operation is performed on all upper bridge arms; and when the short-circuited bridge arm is located at the lower bridge arm, an active short-circuit operation is performed on all lower bridge arms.

[0063] Active short-circuit operation is performed on all upper bridge arms, that is, all upper bridge arms are turned on and all lower bridge arms are turned off. Active short-circuit operation is performed on all lower bridge arms, that is, all lower bridge arms are turned on and all upper bridge arms are turned off.

[0064] The trailer protection method provided by the embodiment of the present invention determines the position where the bridge arm short-circuit occurs. When the position where the bridge arm short-circuit occurs is the upper bridge arm, an active short-circuit operation is performed on all the upper bridge arms, and when the position where the bridge arm short-circuit occurs is the lower bridge arm, an active short-circuit operation is performed on all the lower bridge arms, so that the short-circuit current of each phase is in a balanced state, avoiding damage to the motor and the motor controller caused by excessive short-circuit current of one phase, playing a protective role when the vehicle is towed in this case, ensuring safety, and at the same time, this trailer protection method has strong versatility and good reliability.

[0065] In one embodiment, the trailer protection method also includes: when a bridge arm fault or an overcurrent fault is detected, obtaining all phase current values ​​and a preset current value; when the absolute values ​​of all phase current values ​​are greater than the preset current value, and the duration that all phase current values ​​are greater than the preset current value exceeds a first preset time, determining that a short circuit fault has occurred in the bridge arm.

[0066] Bridge arm fault and overcurrent fault can be detected by the motor controller.

[0067] A bridge arm failure is a situation where a problem occurs in the components that make up the bridge arm in the inverter, causing the bridge arm to fail to work properly. Bridge arm failures include bridge arm short circuit failures and bridge arm open circuit failures. Overcurrent failures are a phenomenon in which the current value exceeds the maximum rated current value that the components in the bridge arm can withstand in the inverter, causing component damage or even motor system collapse. Overcurrent failures include overload and bridge arm short circuit failures. It can be concluded that there are multiple reasons for bridge arm failures or overcurrent failures, one of which is a bridge arm short circuit failure.

[0068] The phase current value can be acquired by the current sensor. The preset current value is a pre-stored value that can be directly obtained.

[0069] After all phase current values ​​are obtained, low-pass filtering is performed on all phase current values ​​to obtain processed phase current values, and then the absolute values ​​of the processed phase current values ​​are compared with the preset current values. This can reduce or even remove high-frequency noise components, making the current signal smoother and more stable.

[0070] It should be noted that, in the case of detecting a bridge arm fault or an overcurrent fault, before using the above method to detect whether a short circuit fault occurs in the bridge arm, determine whether the following conditions are met: the low-voltage power supply of the motor controller is normal, the current sensor is normal, the motor controller is not in an active three-phase short-circuit state, and the motor speed is greater than the set speed value. After determining that the above conditions are met, the above method is used to detect whether a short circuit fault occurs in the bridge arm, which can ensure the accuracy and reliability of the detection.

[0071] In one embodiment, step S110 specifically includes: when it is determined that a short circuit occurs in the bridge arm, all phase current values ​​are obtained; based on all phase current values, a target phase current value is determined; wherein the target phase current value is the phase current value with the largest absolute value among all phase current values; when the target current value is a positive value, it is determined that a short circuit occurs in the upper bridge arm, and when the target current value is a negative value, it is determined that a short circuit occurs in the lower bridge arm.

[0072] In this embodiment, the position where the short circuit occurs in the bridge arm is determined according to the positive or negative sign of the target phase current value.

[0073] In one embodiment, when the hardware configuration is relatively high, the bridge arm error information can be obtained through the driver chip. In this embodiment, step S110 specifically includes: when it is determined that the bridge arm is short-circuited, all bridge arm error information is obtained; when there is at least one upper bridge arm error information in all bridge arm error information, it is determined that the upper bridge arm is short-circuited, and when there is at least one lower bridge arm error information in all bridge arm error information, it is determined that the lower bridge arm is short-circuited.

[0074] Figure 2 FIG. 1 is a processing flow chart of a method for determining a position where a bridge arm short circuit occurs according to an embodiment of the present invention. Figure 2 The method for determining the position where the bridge arm short-circuit occurs includes steps S201 to S210.

[0075] Step S201, determining whether a bridge arm fault or an overcurrent fault is detected.

[0076] If the execution result of step S201 is no, the subsequent steps are no longer executed.

[0077] If the execution result of step S201 is yes, step S202 is executed to determine whether the following conditions are met: the low-voltage power supply of the motor controller is normal, the current sensor is normal, the motor controller is not in an active three-phase short-circuit state, and the motor speed is greater than the set speed value.

[0078] If the execution result of step S202 is no, the subsequent steps are no longer executed.

[0079] If the result of executing step S202 is yes, step S203 is executed to obtain all phase current values ​​and preset current values.

[0080] Step S204 , determining whether the absolute values ​​of all phase current values ​​are greater than a preset current value, and whether the duration that all phase current values ​​are greater than the preset current value exceeds a first preset time.

[0081] If the result of executing step S204 is yes, step S205 is executed to determine whether a short circuit fault occurs in the bridge arm.

[0082] When the execution result of step S204 is no, step S206 is executed to determine whether a short circuit fault occurs in the bridge arm.

[0083] Step S207, determining a target phase current value according to all phase current values; wherein the target phase current value is the phase current value with the largest absolute value among all phase current values.

[0084] Step S208, determining whether the target phase current value is positive or negative.

[0085] Step S209: when the target phase current value is a positive value, it is determined that a short circuit occurs in the upper bridge arm.

[0086] Step S210: When the target phase current value is a negative value, it is determined that a short circuit occurs in the lower bridge arm.

[0087] In one embodiment, the trailer protection method further includes: sending a heat dissipation request to a vehicle controller, so that the vehicle controller controls the heat dissipation system to perform a heat dissipation operation.

[0088] The cooling system can use fans, water pumps, oil pumps, etc. to perform cooling operations to enable maximum cooling capacity and alleviate the problem of overheating of the motor and motor controller caused by short circuits.

[0089] In one embodiment, the trailer protection method also includes: when a bridge arm short circuit fault is detected and the vehicle is driven by a power source other than the power source where the bridge arm short circuit fault occurs, controlling the vehicle speed to be less than a preset speed so that the actual short circuit current value is less than the rated working current value.

[0090] The power source other than the power source where the bridge arm short circuit fault occurs may be a power battery drive device or an engine.

[0091] The rated operating current value is the maximum current value allowed by the motor control system when it is working normally. By limiting the vehicle speed, the actual short-circuit current value is less than the rated operating current value, which can ensure the safety of the motor control system.

[0092] In one embodiment, the trailer protection method also includes: obtaining a rated operating current value and a pre-calibrated correspondence, wherein the pre-calibrated correspondence records the rated operating current values ​​corresponding to different motor speeds; finding a first motor speed corresponding to the rated operating current value according to the rated operating current value and the pre-calibrated correspondence; and controlling the motor to operate at a speed lower than the first motor speed so that the vehicle speed is lower than a preset speed.

[0093] The calibrated correspondence can be a list. A list records the correspondence between the motor speed and the rated operating current value.

[0094] In one embodiment, the trailer protection method further includes: obtaining an actual short-circuit current value and a preset coefficient; determining a second motor speed according to the actual short-circuit current value, a rated operating current value, a first motor speed and a preset coefficient; and controlling the motor to operate at a speed lower than the second motor speed so that the vehicle speed is lower than the preset speed.

[0095] The actual short-circuit current value is the phase current value with the largest absolute value among all the phase current values ​​obtained. The preset coefficient is a pre-stored value that can be directly obtained.

[0096] Based on the following calculation formula, the second motor speed is obtained:

[0097] n2=n1+I 实 -I 额 )×α

[0098] Wherein, n2 is the second motor speed, n1 is the first motor speed, I 实 is the actual short-circuit current value, I 额 is the rated working current value, and α is the preset coefficient.

[0099] After calculating the speed of the second motor based on the above calculation formula, the motor is controlled to operate at a speed lower than the speed of the second motor so that the vehicle speed is lower than the preset speed. In this way, closed-loop adjustment of the preset speed can be achieved to ensure that the actual short-circuit current value is lower than the rated operating current value, thereby ensuring the safety of the motor control system.

[0100] It should be noted that after obtaining the actual short-circuit current value, the actual short-circuit current value is low-pass filtered to obtain the processed actual short-circuit current value, and then the processed actual short-circuit current value is used to perform subsequent operations. This can reduce or even remove high-frequency noise components and make the current signal smoother and more stable.

[0101] In one embodiment, whether a vehicle is being towed may be determined according to the following method: when all power sources of the vehicle are in an inoperative state and the position sensor is operating normally, the actual motor speed is obtained; when the actual motor speed exceeds a preset motor speed, and the duration during which the actual motor speed exceeds the preset motor speed exceeds a second preset time, it is determined that the vehicle is being towed.

[0102] When the vehicle is a pure electric vehicle, all power sources are in an inoperative state, that is, the motor control system is in a shutdown state. When the vehicle is a hybrid vehicle, all power sources are in an inoperative state, that is, the motor control system and other power drive systems are in a shutdown state.

[0103] Using the position sensor to detect the movement of the vehicle's position does not determine whether the movement is caused by the vehicle being towed. Further detection is required based on the actual speed of the motor to ensure the accuracy of the detection of whether the vehicle is being towed.

[0104] In one embodiment, whether a vehicle is being towed may be determined according to the following method: when all power sources of the vehicle are in an inoperative state and a position sensor fails, the actual wheel speed of the vehicle's driving wheels is obtained; when the actual wheel speed of the vehicle's driving wheels exceeds a preset vehicle speed, and the duration for which the actual wheel speed of the vehicle's driving wheels exceeds the preset vehicle speed exceeds a third preset time, it is determined that the vehicle is being towed.

[0105] When the position sensor fails, it cannot be used to detect whether the position of the vehicle has moved. In this embodiment, further detection is performed based on the actual wheel speed of the vehicle's driving wheels, which can ensure the accuracy of the detection of whether the vehicle is being towed.

[0106] Figure 3 FIG. 1 is a processing flow chart of a method for detecting whether a vehicle is being towed according to an embodiment of the present invention. Figure 3 The method for detecting whether the vehicle is being towed includes steps S301 to S308.

[0107] Step S301, determining whether the power source of the vehicle is in working state.

[0108] If the execution result of step S301 is yes, the subsequent operations are no longer executed.

[0109] If the result of executing step S301 is no, step S302 is executed to determine whether the position sensor fails.

[0110] If the execution result of step S302 is no, step S303 is executed to obtain the actual speed of the motor.

[0111] Step S304 , determining whether the actual motor speed exceeds the preset motor speed, and whether the duration of the actual motor speed exceeding the preset motor speed exceeds a second preset time.

[0112] If the result of executing step S304 is yes, step S305 is executed to determine whether the vehicle is towed.

[0113] If the execution result of step S304 is no, step S306 is executed to determine whether the vehicle is being towed.

[0114] When the result of executing step S302 is yes, step S307 is executed to obtain the actual wheel speed of the vehicle driving wheel.

[0115] Step S308, determining whether the actual wheel speed of the vehicle driving wheel exceeds the preset vehicle speed, and whether the duration of the actual wheel speed of the vehicle driving wheel exceeding the preset vehicle speed exceeds a third preset time.

[0116] If the result of executing step S308 is yes, step S305 is executed to determine whether the vehicle is towed.

[0117] If the result of executing step S308 is no, step S306 is executed to determine whether the vehicle is being towed.

[0118] The trailer protection method provided by the present invention is described below with a specific embodiment. Figure 4 , the trailer protection method includes steps S401 to S409.

[0119] Step S401, detecting whether a motor controller has a non-drivable fault.

[0120] If the detection result of step S401 is negative, the subsequent operations are not performed.

[0121] If the detection result of step S401 is yes, step S402 is executed to determine whether a short circuit fault occurs in the bridge arm.

[0122] If the execution result of step S402 is no, the subsequent operations are no longer executed.

[0123] If the result of executing step S402 is yes, step S403 is executed to issue a towing restriction alarm prompt.

[0124] Step S404, detecting whether the vehicle is being towed.

[0125] If the execution result of step S404 is no, the subsequent steps are no longer executed.

[0126] If the result of executing step S404 is yes, step S405 is executed to determine the position where the short circuit occurs in the bridge arm.

[0127] Step S406, when the short-circuited bridge arm is located at the upper bridge arm, an active short-circuit operation is performed on all upper bridge arms; and when the short-circuited bridge arm is located at the lower bridge arm, an active short-circuit operation is performed on all lower bridge arms.

[0128] When the execution result of step S404 is yes, step S407 is further executed to send a heat dissipation request to the vehicle controller so that the vehicle controller controls the heat dissipation system to perform a heat dissipation operation.

[0129] When the execution result of step S404 is yes, step S408 is also executed. When the vehicle is driven by its own other power source, the vehicle speed is controlled to be less than the preset speed so that the actual short-circuit current value is less than the rated working current value.

[0130] One embodiment of the present invention provides a drag protection device, such as Figure 5 The drag protection device 500 includes a bridge arm short circuit position determination module 510 and an active short circuit module 520 .

[0131] The bridge arm short circuit position determination module 510 is used to determine the position where the bridge arm short circuit occurs when a bridge arm short circuit fault is detected and the vehicle is towed; wherein the position is the upper bridge arm or the lower bridge arm.

[0132] The active short-circuit module 520 is used to perform an active short-circuit operation on all upper bridge arms when the bridge arm short-circuit occurs at the upper bridge arm, and to perform an active short-circuit operation on all lower bridge arms when the bridge arm short-circuit occurs at the lower bridge arm.

[0133] In one embodiment, the bridge arm short circuit position determination module 510 is also used to obtain all phase current values ​​when it is determined that a bridge arm short circuit occurs; determine the target phase current value based on all phase current values; wherein the target phase current value is the phase current value with the largest absolute value among all phase current values; when the target current value is a positive value, determine that the upper bridge arm short circuit occurs, and when the target current value is a negative value, determine that the lower bridge arm short circuit occurs.

[0134] In one embodiment, the bridge arm short circuit position determination module 510 is also used to obtain all bridge arm error information when it is determined that a bridge arm short circuit occurs; when there is at least one upper bridge arm error information in all bridge arm error information, it is determined that a short circuit occurs in the upper bridge arm; and when there is at least one lower bridge arm error information in all bridge arm error information, it is determined that a short circuit occurs in the lower bridge arm.

[0135] In one embodiment, the towing protection device further includes a short circuit fault determination module.

[0136] The short-circuit fault determination module is used to obtain all phase current values ​​and preset current values ​​when a bridge arm fault or overcurrent fault is detected; when the absolute values ​​of all phase current values ​​are greater than the preset current value, and the duration that all phase current values ​​are greater than the preset current value exceeds the first preset time, it is determined that a short-circuit fault has occurred in the bridge arm.

[0137] In one embodiment, the towing protection device further includes a heat dissipation request sending module.

[0138] The heat dissipation request sending module is used to send a heat dissipation request to the vehicle controller so that the vehicle controller controls the heat dissipation system to perform a heat dissipation operation.

[0139] In one embodiment, the drag protection device further includes a vehicle speed control module.

[0140] The vehicle speed control module is used to control the vehicle speed to be less than the preset speed when a bridge arm short-circuit fault is detected and the vehicle is driven by other power sources, so that the actual short-circuit current value is less than the rated operating current value.

[0141] In one embodiment, the vehicle speed control module is also used to obtain the rated operating current value and a pre-calibrated correspondence, wherein the pre-calibrated correspondence records the rated operating current value corresponding to different motor speeds; according to the rated operating current value and the pre-calibrated correspondence, the first motor speed corresponding to the rated operating current value is found; and the motor is controlled to operate at a speed lower than the first motor speed so that the vehicle speed is lower than the preset speed.

[0142] In one embodiment, the vehicle speed control module is also used to obtain an actual short-circuit current value and a preset coefficient; determine the second motor speed based on the actual short-circuit current value, the rated operating current value, the first motor speed and the preset coefficient; and control the motor to operate at a speed lower than the second motor speed so that the vehicle speed is lower than the preset speed.

[0143] In one embodiment, the towing protection device further includes a towing determination module.

[0144] The towing determination module is used to obtain the actual motor speed when all power sources are in an inoperative state and the position sensor is operating normally; when the actual motor speed exceeds the preset motor speed and the duration for which the actual motor speed exceeds the preset motor speed exceeds a second preset time, determine that the vehicle is towed.

[0145] In one embodiment, the towing determination module is also used to obtain the actual wheel speed of the vehicle's driving wheels when all power sources of the vehicle are in an inoperative state and the position sensor fails; when the actual wheel speed of the vehicle's driving wheels exceeds a preset vehicle speed, and the duration for which the actual wheel speed of the vehicle's driving wheels exceeds the preset vehicle speed exceeds a third preset time, it is determined that the vehicle is towed.

[0146] An embodiment of the present invention provides an electronic device, such as Figure 6 The electronic device 600 includes a memory 620 and a processor 610. The memory 620 stores a computer program, and the computer program is used to control the processor 610 to operate so as to execute the towing protection method in any of the above embodiments.

[0147] An embodiment of the present invention provides a motor control system, which includes an inverter, a motor, and a trailer protection device or an electronic device as provided in any of the above embodiments. The inverter and the motor are both electrically connected to the trailer protection device or the electronic device. Figure 7 The inverter 710 and the motor 720 are both electrically connected to the electronic device 730 .

[0148] One embodiment of the present invention provides a vehicle, such as Figure 8 The vehicle includes a motor control system as described in any of the above embodiments.

[0149] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. For the device embodiment, its related parts can be referred to the partial description of the method embodiment.

[0150] The above is a description of a specific embodiment of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0151] The embodiments of the present specification may be systems, methods and / or computer program products. The computer program product may include a computer-readable storage medium carrying computer instructions for causing a processor to implement various aspects of the embodiments of the present specification.

[0152] A computer-readable storage medium may be a tangible device that can hold and store computer instructions used by a computer instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which computer instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0153] The computer instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device through a network layer, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network layer may include copper transmission cables, optical fiber transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. The network layer adapter card or network layer interface in each computing / processing device receives the computer instructions from the network layer and forwards the computer instructions for storage in a computer-readable storage medium in each computing / processing device.

[0154] The flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the systems, methods and computer program products according to the multiple embodiments of this specification. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a computer instruction, and a part of a module, a program segment or a computer instruction contains one or more executable computer instructions for realizing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or the flowchart, and the combination of the boxes in the block diagram and / or the flowchart can be implemented by a dedicated hardware-based system that performs the specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions. It is well known to those skilled in the art that it is equivalent to implement it by hardware, implement it by software, and implement it by combining software and hardware.

[0155] The embodiments of the present specification have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art without departing from the scope of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A trailer protection method, characterized in that: include: When a bridge arm short circuit fault is detected and the vehicle is towed, determining the position where the bridge arm short circuit occurs; wherein the position is the upper bridge arm or the lower bridge arm; When the short-circuited bridge arm is located at the upper bridge arm, an active short-circuit operation is performed on all upper bridge arms; and when the short-circuited bridge arm is located at the lower bridge arm, an active short-circuit operation is performed on all lower bridge arms.

2. The method according to claim 1, characterized in that Determining the position where the bridge arm short-circuit occurs includes: When it is determined that a short circuit occurs in the bridge arm, all phase current values ​​are obtained; Determine a target phase current value according to all the phase current values; wherein the target phase current value is the phase current value with the largest absolute value among all the phase current values; When the target current value is a positive value, it is determined that the upper bridge arm is short-circuited, and when the target current value is a negative value, it is determined that the lower bridge arm is short-circuited.

3. The method according to claim 1, characterized in that Determining the position where the bridge arm short-circuit occurs includes: When it is determined that a short circuit occurs in a bridge arm, error information of all bridge arms is obtained; When at least one upper bridge arm error information exists in all the bridge arm error information, it is determined that a short circuit occurs in the upper bridge arm; and when at least one lower bridge arm error information exists in all the bridge arm error information, it is determined that a short circuit occurs in the lower bridge arm.

4. The method according to any one of claims 1 to 3, characterized in that: The method further comprises: When a bridge arm fault or an overcurrent fault is detected, all phase current values ​​and a preset current value are obtained; When the absolute values ​​of all the phase current values ​​are greater than the preset current value, and the duration that all the phase current values ​​are greater than the preset current value exceeds a first preset time, it is determined that a short circuit fault occurs in the bridge arm.

5. The method according to claim 1, characterized in that The method further comprises: A heat dissipation request is sent to the vehicle controller so that the vehicle controller controls the heat dissipation system to perform a heat dissipation operation.

6. The method according to claim 1, characterized in that The method further comprises: When a bridge arm short circuit fault is detected and the vehicle is driven by a power source other than the power source where the bridge arm short circuit fault occurs, the vehicle speed is controlled to be less than a preset speed so that the actual short circuit current value is less than the rated working current value.

7. The method according to claim 6, characterized in that The method further comprises: Obtaining a rated working current value and a pre-calibrated corresponding relationship, wherein the pre-calibrated corresponding relationship records the rated working current values ​​corresponding to different motor speeds; According to the corresponding relationship between the rated working current value and the pre-calibrated value, a first motor speed corresponding to the rated working current value is found; The motor is controlled to rotate at a speed lower than the first motor speed, so that the vehicle speed is lower than a preset vehicle speed.

8. The method according to claim 7, characterized in that The method further comprises: Obtaining actual short-circuit current value and preset coefficient; Determine the second motor speed according to the actual short-circuit current value, the rated operating current value, the first motor speed and the preset coefficient; The motor is controlled to rotate at a speed lower than the second motor speed, so that the vehicle speed is lower than a preset vehicle speed.

9. The method according to claim 1, characterized in that: The method further comprises: When all power sources of the vehicle are in an inoperative state and the position sensor is operating normally, the actual speed of the motor is obtained; When the actual motor speed exceeds the preset motor speed, and a duration during which the actual motor speed exceeds the preset motor speed exceeds a second preset time, it is determined that the vehicle is towed.

10. The method according to claim 1, characterized in that The method further comprises: When all power sources of the vehicle are in an inoperative state and the position sensor fails, the actual wheel speed of the vehicle driving wheel is obtained; When the actual wheel speed of the driving wheels of the vehicle exceeds the preset vehicle speed, and the duration for which the actual wheel speed of the driving wheels of the vehicle exceeds the preset vehicle speed exceeds a third preset time, it is determined that the vehicle is towed.

11. A trailer protection device, characterized in that: include: A bridge arm short circuit position determination module, used to determine the position where the bridge arm short circuit occurs when a bridge arm short circuit fault is detected and the vehicle is towed; wherein the position is the upper bridge arm or the lower bridge arm; The active short-circuit module is used to perform an active short-circuit operation on all upper bridge arms when the short-circuit position of the bridge arm is the upper bridge arm, and to perform an active short-circuit operation on all lower bridge arms when the short-circuit position of the bridge arm is the lower bridge arm.

12. An electronic device, characterized in that: The method comprises a memory and a processor, wherein the memory stores a computer program, and the computer program is used to control the processor to operate so as to execute the trailer protection method according to any one of claims 1 to 10.

13. A motor control system, characterized in that: The invention comprises an inverter, a motor and the trailer protection device according to claim 11 or the electronic device according to claim 12; wherein: The inverter and the motor are both electrically connected to the trailer protection device or the electronic device.

14. A vehicle, characterized in that: Comprising the motor control system as claimed in claim 13.

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