Fault processing method of central distributed electric drive system and vehicle

Abstract

The invention discloses a fault processing method of a central distributed electric drive system and a vehicle, and belongs to the technical field of vehicle control. The central distributed electric drive system comprises a motor controller, a first motor and a second motor, the first motor and the second motor are coaxial, and the method comprises the steps that the motor controller controls the first motor and the second motor to enter a safety mode under the condition that the first motor or the second motor has a preset fault, and the preset fault is the fault with the highest severity level; the safety mode comprises a free-wheel FW mode; taking the motor entering the FW mode as a current motor, and controlling the current motor to maintain the FW mode under the condition that the current motor has a preset fault; and under the condition that the current motor does not have the preset fault, controlling the current motor to exit the FW mode. According to the technical scheme provided by the invention, when any motor has the fault with the highest severity level, the two coaxial motors enter the safety mode, so that instantaneous response synchronization of the left wheel and the right wheel is guaranteed, and the safety of the vehicle is improved.

Description

Technical Field

[0001] The present application belongs to the field of vehicle control technology, and in particular, relates to a fault handling method and a vehicle for a central distributed electric drive system. Background Art

[0002] The electric drive system is one of the core systems of new energy vehicles. Due to the complexity of the working environment, electric drive system failures often occur, and after a failure, the vehicle will show power loss, vehicle breakdown, etc., which poses a serious threat to driver safety and manufacturer reputation. The electric drive system includes a central distributed electric drive system and a central integrated electric drive system. Among them, the central distributed electric drive system usually includes two motor controllers and four motors. Each motor controller controls the corresponding wheel by controlling two coaxial motors.

[0003] According to the general definition of fault levels, faults can generally be divided into three levels according to severity, namely, level 1 faults, level 2 faults, and level 3 faults, among which level 3 faults are the most severe. In related technologies, after a level 3 fault occurs in a central distributed electric drive system, the faulty motor needs to enter a safe state instantly. Since the torque and speed of the faulty motor are facing huge fluctuations, and the other normal motor on the same axis is still responding normally to the torque request of the vehicle control unit (VCU), this will cause the vehicle to be in an unstable state, leading to safety issues. Summary of the invention

[0004] The embodiments of the present application provide a fault handling method and vehicle for a central distributed electric drive system, which can ensure that the vehicle is in a stable state and improve the safety of the vehicle, at least to a certain extent, when a motor fails in the central distributed electric drive system.

[0005] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by the practice of the present application.

[0006] According to a first aspect of an embodiment of the present application, a fault handling method of a central distributed electric drive system is provided. The central distributed electric drive system includes a motor controller, a first motor, and a second motor, wherein the first motor and the second motor are coaxially arranged. The fault handling method of the central distributed electric drive system includes:

[0007] The motor controller controls the first motor and the second motor to enter a safety mode when a preset fault occurs in the first motor or the second motor, wherein the preset fault is a fault with the highest severity level, and the safety mode includes a free-wheeling FW mode;

[0008] The motor that has entered the FW mode is used as the current motor. When a preset fault occurs in the current motor, the current motor is controlled to maintain the FW mode.

[0009] When the current motor does not have a preset fault, the current motor is controlled to exit the FW mode.

[0010] In some embodiments, the safety mode further includes an active short circuit control ASC mode, which controls the first motor and the second motor to enter the safety mode, including:

[0011] The state of the state machine is switched to the pre-fault state to control the first motor and the second motor to enter the FW mode or the ASC mode respectively.

[0012] In some embodiments, controlling the first motor and the second motor to enter the FW mode or the ASC mode respectively includes:

[0013] When the speed of the first motor or the second motor is greater than a preset mode switching threshold, controlling the corresponding motor to enter the ASC mode;

[0014] When the rotation speed of the first motor or the second motor is less than or equal to the preset mode switching threshold, the corresponding motor is controlled to enter the FW mode.

[0015] In some embodiments, controlling the current motor to maintain the FW mode includes:

[0016] Switch the state of the state machine to the fault state to control the current motor to maintain the FW mode.

[0017] In some embodiments, after controlling the current motor to maintain the FW mode, the fault handling method of the central distributed electric drive system further includes:

[0018] According to the current motor speed, determine the rated torque of the current motor in FW mode;

[0019] The calibrated torque is sent to the vehicle controller so that the vehicle controller performs torque control on motors other than the current motor according to the calibrated torque.

[0020] In some embodiments, controlling the current motor to exit the FW mode includes:

[0021] Switch the state of the state machine from the pre-fault state to the ready state to respond to the state request of the vehicle controller;

[0022] When the state request is a torque request, the current motor is controlled to switch from the FW mode to the zero torque mode;

[0023] Get the current current of the motor in zero torque mode;

[0024] When the current is in a stable state within a preset time period, the torque of the current motor is controlled according to the torque request.

[0025] In some embodiments, the torque of the current motor is controlled according to the torque request, including:

[0026] Get the torque slope;

[0027] Controls the torque output to the current motor based on the torque request and the torque slope.

[0028] According to a second aspect of an embodiment of the present application, a vehicle is provided, comprising a processor and a memory, wherein the memory stores computer program instructions that can be executed by the processor, and when the processor executes the computer program instructions, the steps of any method of the first aspect described above are implemented.

[0029] According to a third aspect of an embodiment of the present application, a computer-readable storage medium is provided, in which computer program instructions are stored. When the computer program instructions are executed by a processor, the processor is prompted to implement the steps of any method of the first aspect described above.

[0030] According to a fourth aspect of an embodiment of the present application, a computer program product is provided, including a computer program. When the computer program is executed by a processor, it prompts the processor to implement the steps of any method of the first aspect described above.

[0031] In the present application, when any motor has the most serious fault, the two coaxial motors are put into safety mode to ensure the synchronization of the instantaneous response of the left and right wheels. Even if the torque and speed of the faulty motor fluctuate greatly, since the two coaxial motors have the same response and the torque is also the same in safety mode, it will not affect the vehicle's dynamic control, thereby avoiding vehicle instability or even loss of control due to untimely torque coordination control, thereby improving the safety of the vehicle.

[0032] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0034] Figure 1 A schematic diagram of the structure of a central distributed electric drive system according to some embodiments of the present application is shown;

[0035] Figure 2 A schematic diagram of the structure of a central integrated electric drive system is shown;

[0036] Figure 3 shows the signal flow diagram of torque management when the central integrated electric drive system fails;

[0037] Figure 4 A schematic diagram of a process flow of a method for handling a fault of a central distributed electric drive system according to some embodiments of the present application is shown;

[0038] Figure 5 A jump logic diagram of a state machine of a motor controller according to some embodiments of the present application is shown;

[0039] Figure 6 A simulation schematic diagram of the current motor exiting the FW mode according to some embodiments of the present application is shown;

[0040] Figure 7 A block diagram of a fault processing device for a central distributed electric drive system according to some embodiments of the present application is shown;

[0041] Figure 8 A schematic structural diagram of a vehicle according to some embodiments of the present application is shown. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0043] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present application. However, those skilled in the art will appreciate that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps, etc. can be adopted. In other cases, known methods, devices, realizations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0044] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0045] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0046] In order to make those skilled in the art better understand the present application, firstly, Figure 1 A brief description is given of the central distributed electric drive system involved in this application.

[0047] Figure 1 The structure diagram of the central distributed electric drive system according to some embodiments of the present application is shown. Figure 1 As shown, the central distributed electric drive system includes two motor controllers and four motors, each motor controls one wheel, and each motor controller controls the corresponding wheel by controlling two coaxial motors. In the implementation process, the motor controller can be a microcontroller unit (MCU) or other devices that can realize motor control. The specific hardware form of the motor controller is not limited by the embodiment of the present application.

[0048] Before introducing the fault handling method of the central distributed electric drive system of the embodiment of the present application, a brief introduction is first given to the central integrated electric drive system in the related art and its torque management logic when a fault occurs.

[0049] Figure 2 A schematic diagram of the structure of the central integrated electric drive system is shown in FIG. Figure 2 As shown in the figure, for dual-motor four-wheel drive models, the central integrated electric drive system includes two motor controllers and two motors. Each motor controls two coaxial wheels, and each motor controller controls one motor to achieve control of the corresponding two wheels. When a single motor fails, it will enter a safe mode, and the vehicle will rely on another normal motor to provide driving force.

[0050] Figure 3 The signal flow diagram of torque management when a central integrated electric drive system fails is shown. Figure 3 In this example, the motor controller is an MCU. Figure 3As shown in the figure, the logic of torque management when the central integrated electric drive system fails is as follows: 1. MCU sends external characteristic capabilities to VCU according to its own working status (for example, the maximum range of drive / feedback torque that VCU can request); 2. VCU sends a torque request to MCU according to driver needs; 3. After receiving the torque request, MCU controls the motor to execute the corresponding torque, distributes the torque to the left and right wheels through the differential, and feeds back the actual output torque to VCU to complete torque management; 4. If the motor fails, MCU sends the corresponding fault level to VCU, and limits the external characteristic capabilities of MCU before sending it to VCU. Usually, a level 1 fault will limit the output torque, a level 2 fault will prohibit the output torque, and a level 3 fault will require entering a safe state. When the motor is in normal or faulty state, it is processed according to the above 1-4 processes. Among them, a level 3 fault refers to a fault that requires the motor to enter a safe mode, such as a safety-related fault or a fault that will have a significant impact on the vehicle; a level 2 fault refers to a fault that requires prohibiting the output torque, such as a fault that needs to be handled at a vehicle maintenance site as soon as possible; a level 1 fault refers to a fault that requires limiting the output torque, such as a fault that does not need to be handled at a vehicle maintenance site as soon as possible and can be handled during vehicle maintenance.

[0051] The central distributed electric drive system is controlled by a single motor controller to control two motors. If the torque management logic of the traditional central centralized electric drive system is still maintained, that is, the single motor in the torque management logic is only modified to a dual motor, then under the first and second level faults, the output torque of the faulty motor will be limited or prohibited, and the MCU can continue to interact with the VCU for torque information through the external characteristic capability to achieve rapid response, thereby allowing the vehicle to drive safely. However, under the third level fault, the faulty motor needs to enter the safe state instantly, which will bring two problems: 1. When the motor enters the safe mode, whether it is the active short circuit control (ASC) or free wheeling (FW) mode, the torque and speed of the faulty motor are facing huge fluctuations, while the other normal motor on the same axis is still responding to the torque request of the VCU normally, and the vehicle is in an unstable state; 2. After entering the safe mode, the faulty motor cannot send out its actual output torque, so its external characteristic capability and output torque are generally sent as 0Nm. At this time, if the VCU performs torque coordination control on the faulty motor as 0Nm, it will bring about the problem of inaccurate vehicle dynamics control.

[0052] Based on this, the embodiment of the present application designs a fault handling method for a central distributed electric drive system to solve the above two problems.

[0053] Figure 4 FIG. 1 is a flow chart showing a method for handling a fault of a central distributed electric drive system according to some embodiments of the present application. Figure 4As shown, a method for handling faults in a central distributed electric drive system is provided. Figure 1 Taking the motor controller in as an example, the method may include the following steps 401 to 403.

[0054] In step 401, when a preset fault occurs in the first motor or the second motor, the first motor and the second motor are controlled to enter a safety mode, wherein the preset fault is a fault with the highest severity level, and the safety mode includes a free-wheeling FW mode.

[0055] It is understandable that according to the general definition of fault levels, faults can be divided into three levels according to severity: a level 3 fault refers to a fault that requires the motor to enter a safe mode, such as a safety-related fault or a fault that will have a significant impact on the vehicle; a level 2 fault refers to a fault that requires output torque to be prohibited, such as a fault that needs to be handled at a vehicle repair site as soon as possible; a level 1 fault refers to a fault that requires output torque to be limited, such as a fault that does not require a vehicle repair site to be handled as soon as possible and can be handled during vehicle maintenance. The preset fault in the embodiment of the present application can be a level 3 fault. When a level 3 fault occurs in the motor, it is necessary to enter a safe mode and the vehicle enters a limp state. For ease of understanding, the following description is taken as an example of a preset fault being a level 3 fault.

[0056] Safety modes can generally be divided into FW mode and ASC mode. The motor controller enables the motor to enter FW mode by shutting down all the drive modules of the upper and lower bridge arms of the inverter circuit. In FW mode, the motor controller fully shuts down and protects the motor. The motor controller enables the motor to enter ASC mode by fully turning on the drive module of the upper bridge arm of the inverter circuit and fully turning off the drive module of the lower bridge arm, or by fully turning off the drive module of the upper bridge arm and fully turning on the drive module of the lower bridge arm. In ASC mode, the motor controller performs three-phase active short-circuit protection on the motor.

[0057] In some embodiments, the motor controller may switch the state of the state machine to a pre-fault state to control the first motor and the second motor to enter the FW mode or the ASC mode, respectively.

[0058] It is understandable that when any of the first motor and the second motor has a third-level fault, the state of the motor controller will jump from the normal state (such as the Standby state, the Torque state or the Speed ​​state) to the Pre-Fault state. After the motor controller enters the Pre-Fault state, it will control the motor to enter the FW mode or the ASC mode according to the motor speed and the preset mode switching threshold. The preset mode switching threshold refers to the critical speed at which the motor switches between the FW mode and the ASC mode.

[0059] By using the state machine to distinguish the working states of the motor controller, the motor controller can accurately implement motor control under the corresponding working states, thereby improving the control accuracy of the motor.

[0060] In some embodiments, when the speed of the first motor or the second motor is greater than a preset mode switching threshold, the corresponding motor is controlled to enter the ASC mode; when the speed of the first motor or the second motor is less than or equal to the preset mode switching threshold, the corresponding motor is controlled to enter the FW mode.

[0061] It can be understood that after the motor controller enters the Pre-Fault state, it will continuously monitor the speeds of the first motor and the second motor. Taking the first motor as an example, if the speed of the first motor is greater than the preset mode switching threshold, the first motor is controlled to enter the ASC mode. At this time, the speed of the first motor will decrease. If the speed of the first motor is still greater than the preset mode switching threshold, the first motor is controlled to remain in the ASC mode. If the speed of the first motor drops to less than or equal to the preset mode switching threshold, the first motor is controlled to enter the FW mode.

[0062] In step 402, the motor that has entered the FW mode is used as the current motor. When a preset fault occurs in the current motor, the current motor is controlled to maintain the FW mode.

[0063] For example, if the motor that enters the FW mode is the first motor, if a preset fault occurs in the first motor, the first motor is controlled to continue to remain in the FW mode.

[0064] In some embodiments, the motor controller may switch the state of the state machine to a fault state to control the current motor to maintain the FW mode.

[0065] Figure 5 FIG. 2 shows a schematic diagram of the jump logic of the state machine of the motor controller according to some embodiments of the present application. Figure 5 As shown in the figure, taking the motor controller as MCU as an example, the states of the MCU state machine include Standby state, Torque state, Speed ​​state, Pre-Fault state and Fault state. Among them, VCU_StateCmd is the state request of VCU to MCU; FaultLevel is the fault severity level of MCU.

[0066] Depend on Figure 5It can be seen that in the current driving cycle, when any of the two coaxial motors has a level 3 fault (FaultLevel==3), both motors will enter the Pre-Fault state, so that the motor enters the ASC / FW safety mode. The MCU is reversible from the normal state to the Pre-Fault state. If VCU_StateCmd is normal, FaultLevel!=3, and MCUL_FaultState==FW, the MCU can jump out of the Pre-Fault state and continue to respond to the VCU status request. The MCU is irreversible from the Pre-Fault state to the Fault state. If FaultLevel==3 and MCUL_FaultState==FW, the MCU enters the Fault state and controls the motor to maintain the FW mode.

[0067] After controlling the current motor to maintain the FW mode, the motor controller can also determine the calibrated torque of the current motor in the FW mode according to the current motor speed; and send the calibrated torque to the vehicle controller so that the vehicle controller can perform torque control on motors other than the current motor according to the calibrated torque.

[0068] It should be noted that if the current motor has a level 3 fault, it will not be able to send out its current actual output torque after entering the safety mode. Therefore, its external characteristic capacity and output torque are generally processed as 0Nm. At this time, if the VCU coordinates the torque of other motors at 0Nm for the current motor, it will bring about the problem of inaccurate vehicle dynamics control.

[0069] During the implementation process, the speed and torque of the motor in FW mode can be calibrated through testing to obtain the corresponding relationship between the speed and torque. When the current motor is in FW mode, the calibrated torque corresponding to the speed of the current motor is found according to the corresponding relationship. The vehicle controller sends the calibrated torque to the VCU, and the VCU controls the torque of other motors with reference to the calibrated torque, thereby solving the problems of high-voltage safety and control accuracy in FW mode.

[0070] In step 403, when the current motor does not have a preset fault, the current motor is controlled to exit the FW mode.

[0071] It is understandable that if the current motor does not have a preset fault, it is necessary to exit the FW mode and resume normal operation.

[0072] In some embodiments, the motor controller can switch the state of the state machine from a pre-fault state to a ready state in response to a state request of the vehicle controller; when the state request is a torque request, control the current motor to switch from FW mode to zero torque mode; obtain the current of the current motor in zero torque mode; and when the current is in a stable state within a preset time, perform torque control on the current motor according to the torque request.

[0073] It is understandable that if the current motor does not have a preset fault, the motor controller can exit from the Pre-Fault state and enter the Standby state. During the state switching process, the motor is always in FW mode. After the motor controller enters the Standby state, it can respond to the state request of the VCU. When the state request is a torque request, the motor is controlled to switch from FW mode to zero torque mode. It should be noted that in FW mode, the motor controller implements full tube protection for the motor, that is, all the drive modules in the upper and lower bridge arms of the inverter circuit are turned off. In order to ensure that the current loop is stable when the current motor responds to torque and avoid instantaneous severe overcurrent, the embodiment of the present application adds a zero torque mode for opening the tube when exiting the FW mode. In zero torque mode, the current motor works, but the output torque is 0Nm. By maintaining a period of 0Nm closed-loop control, the current motor current is in a stable state and the motor controller state is stable. In addition, when selecting the drive module of the motor controller, the open tube current of the current motor in FW mode and at the highest speed can be obtained, and a drive module with a peak current greater than the open tube current can be selected as the drive module of the motor controller to improve the safety of the motor controller.

[0074] In some embodiments, the motor controller may obtain a torque slope; and control the torque output to the current motor according to the torque request and the torque slope.

[0075] Figure 6 FIG. 2 shows a simulation schematic diagram of the current motor exiting the FW mode according to some embodiments of the present application. Figure 6 As shown, after the current motor exits the FW mode, 0Nm torque is used for open-tube control. After the UVW three-phase currents are stable, the torque is increased linearly, and the current motor gradually resumes normal operation.

[0076] By limiting the slope of the torque output to the current motor until the output torque is equal to the torque requested in the torque request of the VCU, abnormal situations such as sudden speed changes and setbacks caused by torque steps can be prevented.

[0077] In the embodiment of the present application, when any motor has the most serious fault, the two coaxial motors enter the safety mode to ensure the synchronization of the instantaneous response of the left and right wheels. Even if the torque and speed of the faulty motor fluctuate greatly, since the two coaxial motors have the same response and the torque is also the same in the safety mode, it will not affect the vehicle's dynamic control, thereby avoiding vehicle instability or even loss of control due to untimely torque coordination control, and improving the safety of the vehicle.

[0078] The following describes an apparatus embodiment of the present application, which can be used to execute the method for handling a central distributed electric drive system fault in the above-mentioned embodiment of the present application. For details not disclosed in the apparatus embodiment of the present application, please refer to the embodiment of the method for handling a central distributed electric drive system fault in the above-mentioned embodiment of the present application.

[0079] Figure 7 A block diagram of a fault handling device for a central distributed electric drive system according to some embodiments of the present application is shown. Figure 7 As shown, the fault handling device of the central distributed electric drive system of an embodiment of the present application includes: a FW mode switching module 701, a FW mode maintaining module 702 and a FW mode exit module 703, wherein the FW mode switching module 701 is used to control the first motor and the second motor to enter a safety mode when a preset fault occurs in the first motor or the second motor, wherein the preset fault is the fault with the highest severity level, and the safety mode includes a free-wheeling FW mode; the FW mode maintaining module 702 is used to use the motor entering the FW mode as the current motor, and when a preset fault occurs in the current motor, control the current motor to maintain the FW mode; the FW mode exit module 703 is used to control the current motor to exit the FW mode when the preset fault does not occur in the current motor.

[0080] In some embodiments, the safety mode also includes an active short circuit control ASC mode, and the FW mode switching module 701 is further used to switch the state of the state machine to a pre-fault state to control the first motor and the second motor to enter the FW or ASC mode respectively.

[0081] In some embodiments, the FW mode switching module 701 is also used to control the corresponding motor to enter the ASC mode when the speed of the first motor or the second motor is greater than the preset mode switching threshold; and to control the corresponding motor to enter the FW mode when the speed of the first motor or the second motor is less than or equal to the preset mode switching threshold.

[0082] In some embodiments, the FW mode maintaining module 702 is further configured to switch the state of the state machine to a fault state to control the current motor to maintain the FW mode.

[0083] In some embodiments, the FW mode maintaining module 702 is also used to determine the calibrated torque of the current motor in the FW mode according to the current motor speed; and send the calibrated torque to the vehicle controller so that the vehicle controller performs torque control on motors other than the current motor according to the calibrated torque.

[0084] In some embodiments, the FW mode exit module 703 is also used to switch the state of the state machine from a pre-fault state to a ready state in response to a state request of the vehicle controller; when the state request is a torque request, control the current motor to switch from FW mode to zero torque mode; obtain the current of the current motor in zero torque mode; and when the current is in a stable state within a preset time, perform torque control on the current motor according to the torque request.

[0085] In some embodiments, the FW mode exit module 703 is further configured to obtain a torque slope; and control the torque output to the current motor according to the torque request and the torque slope.

[0086] Based on the same inventive concept, the embodiment of the present application further provides a vehicle, referring to Figure 8 , shows a schematic diagram of the structure of a vehicle in an embodiment of the present application, wherein the vehicle includes one or more memories 804, one or more processors 802, and at least one computer program (computer program instruction) stored in the memory 804 and executable on the processor 802, and the processor 802 implements the method described above when executing the computer program.

[0087] Among them, Figure 8 In the embodiment of the present invention, a bus architecture (represented by bus 800) is shown, which may include any number of interconnected buses and bridges, and bus 800 links various circuits including one or more processors represented by processor 802 and memory represented by memory 804. Bus 800 may also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. Bus interface 805 provides an interface between bus 800 and receiver 801 and transmitter 803. Receiver 801 and transmitter 803 may be the same element, namely a transceiver, providing a unit for communicating with various other devices over a transmission medium. Processor 802 is responsible for managing bus 800 and general processing, while memory 804 may be used to store data used by processor 802 when performing operations.

[0088] Based on the same inventive concept, an embodiment of the present application provides a computer-readable storage medium, in which computer program instructions are stored. When the computer program instructions are executed by a processor, the processor is prompted to implement the steps of the method as described above.

[0089] Based on the same inventive concept, an embodiment of the present application provides a computer program product, including a computer program. When the computer program product is executed by a processor, it prompts the processor to implement the steps of the method as described above.

[0090] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored as one or more instructions or codes on a computer-readable medium or transmitted via a computer-readable medium. Other examples and implementations are within the scope and spirit of the present application and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these. In addition, each functional unit may be integrated into a processing unit, each unit may exist physically separately, or two or more units may be integrated into one unit.

[0091] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0092] The units described as separate components may or may not be physically separated, and the components of the control device may or may not be physical units, that is, they may be located in one place or distributed in multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0093] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly or all or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk, etc., which can store computer program instructions.

[0094] The above description is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of the claims of the present application.

Claims

1. A method for handling a fault in a central distributed electric drive system, characterized in that: The central distributed electric drive system includes a motor controller, a first motor and a second motor, wherein the first motor and the second motor are coaxially arranged, and the method includes: The motor controller controls the first motor and the second motor to enter a safety mode when a preset fault occurs in the first motor or the second motor, wherein the preset fault is a fault with the highest severity level, and the safety mode includes a free-wheeling FW mode; The motor that has entered the FW mode is used as the current motor, and when the current motor has the preset fault, the current motor is controlled to maintain the FW mode; In a case where the preset fault does not occur in the current motor, the current motor is controlled to exit the FW mode.

2. The fault handling method of the central distributed electric drive system according to claim 1, characterized in that: The safety mode further includes an active short circuit control ASC mode, and the controlling the first motor and the second motor to enter the safety mode includes: The state of the state machine is switched to a pre-fault state to control the first motor and the second motor to enter the FW mode or the ASC mode, respectively.

3. The method for handling a fault of a central distributed electric drive system according to claim 2, characterized in that: The controlling the first motor and the second motor to enter the FW mode or the ASC mode respectively includes: When the speed of the first motor or the second motor is greater than a preset mode switching threshold, controlling the corresponding motor to enter the ASC mode; When the rotation speed of the first motor or the second motor is less than or equal to the preset mode switching threshold, the corresponding motor is controlled to enter the FW mode.

4. The method for handling a fault of a central distributed electric drive system according to claim 2, characterized in that: The controlling the current motor to maintain the FW mode includes: The state of the state machine is switched to a fault state to control the current motor to maintain the FW mode.

5. The method for handling a fault of a central distributed electric drive system according to claim 4, characterized in that: After controlling the current motor to maintain the FW mode, the method further includes: Determining a calibrated torque of the current motor in the FW mode according to the current rotation speed of the motor; The calibrated torque is sent to a vehicle controller, so that the vehicle controller performs torque control on motors other than the current motor according to the calibrated torque.

6. The method for handling a fault of a central distributed electric drive system according to claim 2, characterized in that: The controlling the current motor to exit the FW mode includes: Switching the state of the state machine from the pre-failure state to a ready state to respond to a state request of a vehicle controller; When the state request is a torque request, controlling the current motor to switch from the FW mode to a zero torque mode; Acquire the current of the current motor in the zero torque mode; When the current is in a stable state within a preset time period, the torque of the current motor is controlled according to the torque request.

7. The method for handling faults of a central distributed electric drive system according to claim 6, characterized in that: The performing torque control on the current motor according to the torque request includes: Get the torque slope; The torque output to the current electric machine is controlled based on the torque request and the torque slope.

8. A vehicle comprising a processor and a memory, characterized in that: The memory stores computer program instructions that can be executed by the processor, and when the processor executes the computer program instructions, the steps of the method according to any one of claims 1 to 7 are implemented.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, which, when executed by a processor, prompt the processor to implement the steps of the method according to any one of claims 1 to 7.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the processor is prompted to implement the steps of the method according to any one of claims 1 to 7.

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