Control method of driving motor, motor controller, driving system and vehicle

Abstract

The invention discloses a control method of a driving motor, a motor controller, a driving system and a vehicle, relates to the field of vehicles, and can dynamically adjust torque output by a front wheel motor and a rear wheel motor to reduce nodding and front-back shaking of the vehicle and improve comfort. The control method of the driving motor comprises the steps that under the condition that the vehicle is braked, when the vehicle speed is larger than or equal to a second threshold value and smaller than or equal to a first threshold value, a first driving motor used for driving front wheels of the vehicle is controlled to output positive torque, and a second driving motor used for driving rear wheels of the vehicle is controlled to output first negative torque.

Description

Technical Field

[0001] This application relates to the field of vehicles, and more particularly to a control method for a drive motor, a motor controller, a drive system, and a vehicle. Background Technology

[0002] With the widespread use of vehicles, the upper and lower body of a vehicle are non-rigidly connected by the suspension. During vehicle braking, the upper body compresses the suspension due to inertia, causing a pitching phenomenon, or "nose-diving," where the front of the vehicle dips and the rear rises. Subsequently, after the vehicle stops, the upper body loses its inertia, and the elastic potential energy of the suspension compression is released, causing a pitching phenomenon, or "heel-lift," where the front of the vehicle rises and the rear pulls back.

[0003] This can cause passengers inside the vehicle to feel noticeable back-and-forth swaying during the braking process, affecting their comfort. Summary of the Invention

[0004] This application provides a control method for a drive motor, a motor controller, a drive system, and a vehicle, which can dynamically adjust the torque output of the front wheel motor and the rear wheel motor to reduce vehicle "nodding" and back-and-forth swaying, thereby improving comfort.

[0005] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0006] In a first aspect, a control method for a drive motor is provided, the method comprising: when the vehicle is braking, and when the vehicle speed is greater than or equal to a second threshold and less than or equal to a first threshold, controlling a first drive motor for driving the front wheels of the vehicle to output positive torque, and controlling a second drive motor for driving the rear wheels of the vehicle to output a first negative torque.

[0007] The first threshold is the vehicle speed threshold when prioritizing the vehicle's braking performance without making additional adjustments to the existing braking force distribution between the front and rear wheels. This threshold can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple vehicle speeds when prioritizing the vehicle's braking performance without making additional adjustments to the existing braking force distribution between the front and rear wheels, such as the average, median, or minimum of these speeds. Alternatively, it can be set based on empirical values, such as 10 km / h or 12 km / h.

[0008] The second threshold is the vehicle speed threshold that might be triggered when the additional anti-dive torque output by the drive motor is not promptly deactivated when the vehicle is nearly stopped, potentially causing the vehicle to crouch backward. This threshold can be set according to actual needs. For example, it can be obtained by statistically analyzing the multiple vehicle speeds that might be triggered when the additional anti-dive torque output by the drive motor is not promptly deactivated when the vehicle is nearly stopped, such as the average, median, or minimum of these multiple speeds. Alternatively, it can be set based on empirical values, such as 1 km / h or 1.5 km / h.

[0009] Understandably, when a vehicle brakes, the driver presses the brake pedal, and the brake controller generates a braking control signal based on the pedal's travel. The brakes, in turn, output braking torque to the corresponding wheels to reduce the vehicle's speed. This means braking is performed using the hydraulic braking torque provided by the brakes, which can cause the vehicle to "nod" or "dive." The motor controller can control the drive motors to compensate for torque on the front and rear wheels. Specifically, the motor controller controls the first drive motor to output positive torque, and the second motor controller controls the second drive motor to output negative torque, shifting the vehicle's center of gravity rearward. This reduces the compression of the suspension due to inertia and the forward and backward swaying during braking.

[0010] In the aforementioned control method for the drive motor, the motor controller can, under vehicle braking conditions, control the first drive motor used to drive the front wheels to output positive torque when the vehicle speed is greater than or equal to a second threshold and less than or equal to a first threshold. Since the braking torque acting on the front wheels is the sum of the positive torque output by the first drive motor and the hydraulic braking torque output by the brake, and the positive torque output by the first drive motor is in the opposite direction to the hydraulic braking torque output by the brake, outputting positive torque by the first drive motor can reduce the braking torque acting on the front wheels. Furthermore, the controller controls the second drive motor used to drive the rear wheels to output a first negative torque. Similarly, since the braking torque acting on the front wheels is the sum of the first negative torque output by the first drive motor and the hydraulic braking torque output by the brake, and the first negative torque output by the first drive motor is in the same direction as the hydraulic braking torque output by the brake, outputting first negative torque by the first drive motor can increase the braking torque acting on the rear wheels. This shifts the vehicle's center of gravity rearward, thereby reducing the compression of the suspension due to inertia and the fore-and-aft swaying during braking. Therefore, by dynamically adjusting the torque output of the front wheel motor (first drive motor) and the rear wheel motor (second drive motor), the vehicle's "nodding" and back-and-forth swaying can be reduced, thus improving comfort.

[0011] In one possible implementation of the first aspect, when the vehicle speed is greater than a first threshold, the method further includes: controlling the first drive motor to output a second negative torque and controlling the second drive motor to output a third negative torque; or; controlling the first drive motor to output a first preset torque and controlling the second drive motor to output a second preset torque.

[0012] The first preset torque is the preload torque to offset the gear backlash of the first drive motor, and can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple preload torques to offset the gear backlash of the first drive motor, such as the average, median, or minimum value of multiple preload torques to offset the gear backlash of the first drive motor; it can also be set based on empirical values, such as 1N or 2N.

[0013] The second preset torque is the preload torque to offset the gear backlash of the second drive motor, and can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple preload torques to offset the gear backlash of the second drive motor, such as the average, median, or minimum value of multiple preload torques to offset the gear backlash of the second drive motor; it can also be set based on empirical values, such as 1N or 2N.

[0014] The first and second preset torques are insufficient to accelerate or decelerate the vehicle; they are precisely the preload torques that offset the gap between the gears of the first and second drive motors, respectively, allowing the meshing gear teeth to fit together and eliminating mechanical backlash. This enables the torque output by the corresponding first and second drive motors to transition very smoothly and continuously from no torque to high torque, avoiding impacts caused by gear meshing.

[0015] Understandably, when the first drive motor outputs the first preset torque, it means that the first preset torque output by the first drive motor exactly cancels out the preload torque of the gear backlash of the first drive motor. At this time, the first drive motor is in a "zero torque control" state. When the second drive motor outputs the second preset torque, it means that the second preset torque output by the second drive motor exactly cancels out the preload torque of the gear backlash of the second drive motor. At this time, the second drive motor is in a "zero torque control" state.

[0016] When the vehicle speed exceeds the first threshold, it indicates a high speed, requiring a larger braking torque to brake the vehicle. If the drive motor were to compensate for torque at the wheels, the high speed might necessitate additional adjustments to the existing braking force distribution between the front and rear wheels, impacting the vehicle's normal driving performance. Therefore, torque compensation for the front and rear wheels is unnecessary. This avoids the drive motor's output torque at high speeds requiring additional adjustments to the existing braking force distribution between the front and rear wheels, thus preventing any impact on the vehicle's normal driving performance. In this situation, the drive motor can be in a "zero torque control" state, where the hydraulic braking torque is entirely provided by the brakes. That is, the first motor controller controls the first drive motor to output a first preset torque, and the second motor controller controls the second drive motor to output a second preset torque. Alternatively, the drive motor can be in an "auxiliary braking" state, where, in addition to the hydraulic braking torque provided by the brakes, the drive motor also provides braking torque. That is, the first motor controller controls the first drive motor to output a second negative torque, and the second motor controller controls the second drive motor to output a third negative torque.

[0017] In this implementation, when the vehicle speed exceeds a first threshold, the drive motor can be in a "zero torque control" state, where the brakes provide hydraulic braking torque entirely to the wheels. In this state, the first motor controller controls the first drive motor to output a first preset torque, and the second motor controller controls the second drive motor to output a second preset torque. Alternatively, the drive motor can be in an "auxiliary braking" state, where the brakes provide hydraulic braking torque to the wheels, and the drive motor also provides braking torque to the wheels. In this state, the first motor controller controls the first drive motor to output a second negative torque, and the second motor controller controls the second drive motor to output a third negative torque. This allows for more effective braking at high speeds without requiring torque compensation from the drive motors to the front and rear wheels, thus avoiding any impact on the vehicle's normal driving performance.

[0018] In one possible implementation of the first aspect, the first preset torque is a preload torque that counteracts the gear backlash of the first drive motor, and the second preset torque is a preload torque that counteracts the gear backlash of the second drive motor.

[0019] In this implementation, by setting a preset torque as the preload torque to offset the gear backlash of the drive motor, the torque output by the drive motor can transition very smoothly and continuously from positive torque to negative torque, avoiding impact caused by gear meshing.

[0020] In one possible implementation of the first aspect, when the vehicle speed is less than the second threshold, the method further includes: controlling the first drive motor to output a first preset torque, and controlling the second drive motor to output a second preset torque.

[0021] Understandably, when the vehicle speed is below the second threshold, indicating extremely low speed, the "nose-diving" phenomenon has largely disappeared after the drive motor compensates for torque at speeds greater than or equal to the second threshold and less than or equal to the first threshold. However, if the drive motor continues to compensate for torque at this point, the additional anti-nose-diving torque from the drive motor might not be promptly removed when the vehicle is nearly stopped, potentially causing the vehicle to lurch backward. Therefore, the drive motor can disengage torque compensation for both the front and rear wheels, reverting to a "zero-torque control" state. In this state, the drive motor operates entirely under "zero-torque control," with the brakes providing hydraulic braking torque to the wheels. In other words, the first motor controller controls the first drive motor to output a first preset torque, and the second motor controller controls the second drive motor to output a second preset torque. This prevents the vehicle from lurching backward when it is nearly stopped due to the additional anti-nose-diving torque from the drive motor not being promptly removed.

[0022] In this implementation, at extremely low vehicle speeds, the drive motor can be in a "zero torque control" state, with the hydraulic braking torque provided entirely by the brakes to the wheels. At this time, the first motor controller controls the first drive motor to output a first preset torque, and the second motor controller controls the second drive motor to output a second preset torque. This allows the drive motors to disengage from torque compensation to the front and rear wheels when the vehicle's "nodding" phenomenon has essentially disappeared, and braking is then achieved through the hydraulic braking torque of the brakes, thereby reducing vehicle sway and improving comfort.

[0023] In one possible implementation of the first aspect, the method further includes: reducing a first compensation torque of the first drive motor to zero torque at a target rate greater than a third threshold when the front wheel and / or rear wheel slips, and reducing a second compensation torque of the second drive motor to zero torque; the first compensation torque is used for the first drive motor to output positive torque, and the second compensation torque is used for the second drive motor to output first negative torque.

[0024] The third threshold is the threshold for the rate at which the drive motor rapidly disengages torque compensation from the front and rear wheels, and can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple rates at which the drive motor rapidly disengages torque compensation from the front and rear wheels, such as the average, median, or minimum of these rates; or it can be set based on empirical values, such as 1000 N·m / s or 800 N·m / s.

[0025] It is understandable that reducing the first compensation torque of the first drive motor to zero torque indicates reducing the torque compensation of the first drive motor to the front wheels to zero, i.e., discontinuing torque compensation to the front wheels. Similarly, reducing the second compensation torque of the second drive motor to zero torque indicates reducing the torque compensation of the second drive motor to the rear wheels to zero, i.e., discontinuing torque compensation to the rear wheels.

[0026] In this implementation, when the front and / or rear wheels slip, the drive motor disengages from torque compensation to the front and rear wheels at a relatively fast rate. That is, at a relatively fast rate greater than the third threshold, the first compensation torque of the first drive motor is reduced to zero, and the second compensation torque of the second drive motor is reduced to zero. This can prevent the vehicle from losing control and ensure the stability and safety of the vehicle.

[0027] In one possible implementation of the first aspect, the wheel speeds of the front and / or rear wheels are obtained by a wheel speed sensor, and / or the yaw rate sensor is used to obtain the direction of the front and / or rear wheels to determine that the front and / or rear wheels are slipping.

[0028] In this implementation, when a wheel slips, its speed increases significantly, and / or the vehicle becomes uncontrollable in the directions of translation or rotation. Thus, wheel speed sensors and / or yaw rate sensors can accurately determine whether the front or rear wheels are slipping.

[0029] In one possible implementation of the first aspect, the target wheel is determined to be slipping if the wheel speed of the target wheel is greater than a wheel speed threshold; or, the target wheel is determined to be slipping if the directional deviation angle of the target wheel is greater than an angle threshold; the target wheel is the front wheel and / or the rear wheel.

[0030] The wheel speed threshold is the threshold value for the wheel speed when the wheel slips, and it can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple wheel speeds when the wheel slips, such as the average, median, or minimum value of multiple wheel speeds when the wheel slips; it can also be set based on empirical values, such as 10 km / h.

[0031] The angle threshold is the threshold for the directional deviation angle when the wheel slips, and it can be set according to actual needs. For example, it can be obtained by statistically analyzing the deviation angles in multiple directions when the wheel slips, such as the mean, median, or minimum value of the deviation angles in multiple directions when the wheel slips; it can also be set based on empirical values, such as 10°.

[0032] In this implementation, if the target wheel's speed exceeds a certain threshold, it indicates that the target wheel's speed has significantly increased, surpassing the speed of the non-driving wheels. If the target wheel's directional deviation angle exceeds a certain threshold, it indicates that the target wheel's direction has completely deviated, and the vehicle is out of control. Therefore, it can be determined that the target wheel is slipping. This allows for precise identification of front and / or rear wheel slippage.

[0033] In one possible implementation of the first aspect, the first compensation torque is the difference between a positive torque and a first preset torque, or the difference between a positive torque and a second negative torque; the second compensation torque is the difference between the first negative torque and the second preset torque, or the difference between the first negative torque and a third negative torque.

[0034] In this implementation, the first compensation torque is the compensation torque of the first drive motor from the initial torque to the target torque; that is, the difference between the positive torque and the first preset torque, or the difference between the positive torque and the second negative torque. The second compensation torque is the compensation torque of the second drive motor from the initial torque to the target torque; that is, the difference between the first negative torque and the second preset torque, or the difference between the first negative torque and the third negative torque. The compensation torque between the initial torque and the target torque is, when the initial torque and the target torque are in the same direction, the difference between the target torque and the initial torque; when the initial torque and the first target torque are in opposite directions, the sum of the target torque and the initial torque.

[0035] In one possible implementation of the first aspect, the difference between a first rate at which the first preset torque changes to a positive torque and a second rate at which the second preset torque changes to a first negative torque is less than or equal to a fourth threshold; or the difference between a third rate at which the second negative torque changes to a positive torque and a fourth rate at which the third negative torque changes to a first negative torque is less than or equal to a fourth threshold.

[0036] The fourth threshold is the threshold for the rate difference between the rate at which the first drive motor changes from its initial torque to the target torque and the rate at which the second drive motor changes from its initial torque to the target torque. This threshold can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple rate differences between the first and second drive motors, such as the mean, median, or minimum of these rate differences. Alternatively, it can be set based on empirical values, such as 0 N·m / s or 0.5 N·m / s.

[0037] It is understandable that if the difference between the first rate at which the torque changes from the first preset torque to positive torque and the second rate at which the torque changes from the second preset torque to the first negative torque is less than or equal to the fourth threshold, it indicates that the first and second rates are approximately the same. Similarly, if the difference between the third rate at which the torque changes from the second negative torque to positive torque and the fourth rate at which the torque changes from the third negative torque to the first negative torque is less than or equal to the fourth threshold, it indicates that the third and fourth rates are approximately the same.

[0038] In this implementation, the motor controller controls the rate at which the first drive motor changes from initial torque to target torque to be approximately the same as the rate at which the second drive motor changes from initial torque to target torque. This can reduce vehicle "nodding" and swaying, and synchronize the compensation torque of the drive motors to the front and rear wheels, thereby improving comfort and safety.

[0039] In one possible implementation of the first aspect, when the vehicle speed is less than a first threshold, the positive torque output by the first drive motor is less than or equal to the braking torque of the front wheel brake.

[0040] In this implementation, when the vehicle speed is less than the first threshold, the positive torque output by the first drive motor is less than or equal to the hydraulic braking torque of the front wheel brakes. In other words, the positive torque used to reduce the braking torque acting on the front wheels cannot be greater than the hydraulic braking torque of the front wheel brakes. Otherwise, it will violate the driver's intention to decelerate and instead accelerate or maintain a constant speed, resulting in a significant increase in braking distance or even complete failure, causing a great safety hazard.

[0041] In one possible implementation of the first aspect, the second threshold is 1 km / h and the first threshold is 10 km / h.

[0042] In this implementation method, the empirical value of the second threshold is 1 km / h and the empirical value of the first threshold is 10 km / h. This allows for the dynamic adjustment of the torque output of the front and rear wheel motors in advance and smoothly, reducing vehicle "nodding" and back-and-forth swaying, and improving comfort.

[0043] In a second aspect, a motor controller is provided, including a memory and one or more processors. The memory stores instructions executable by the one or more processors. The memory stores computer program code, which includes computer instructions. When the computer instructions are executed by the processor, the processor performs a motor control method as provided in any of the first aspects.

[0044] Thirdly, a drive system is provided, including a drive motor and a motor controller as provided in the second aspect above; wherein the motor controller includes a first motor controller and a second motor controller, and the drive motor includes a first drive motor and a second drive motor; the first motor controller is used to control the output torque of the first drive motor, and the second motor controller is used to control the output torque of the second drive motor.

[0045] Fourthly, a vehicle is provided, including wheels, a braking system, a battery, and a drive system as provided in the third aspect above; wherein the battery is connected to the drive system and the braking system, the battery is used to provide electrical energy to the drive system and the braking system, the drive system is used to provide driving torque or braking torque to the wheels, and the braking system is used to provide braking torque to the wheels.

[0046] Fifthly, a computer-readable storage medium is provided that stores instructions which, when executed on a computer, enable the computer to perform the control method for the drive motor provided in any of the first aspects above.

[0047] In a sixth aspect, a computer program product containing instructions is provided, which, when run on a computer, enables the computer to execute the control method for the drive motor provided in any of the first aspects above.

[0048] The technical effects of any of the design methods in aspects two through six can be found in the technical effects of different design methods in aspect one, and will not be repeated here. Attached Figure Description

[0049] Figure 1 A schematic diagram of the structure of a vehicle provided in an embodiment of this application;

[0050] Figure 2 A schematic diagram of the structure of a drive system provided in an embodiment of this application;

[0051] Figure 3 This is a schematic diagram of the structure of a motor controller provided in an embodiment of this application;

[0052] Figure 4 This is a schematic diagram of another driving system provided in an embodiment of this application;

[0053] Figure 5 This is a schematic diagram of the structure of a first motor controller provided in an embodiment of this application;

[0054] Figure 6 This is a schematic diagram of the structure of a second motor controller provided in an embodiment of this application;

[0055] Figure 7This is a schematic diagram of the structure of a braking system provided in an embodiment of this application;

[0056] Figure 8 This is a schematic diagram illustrating how a motor controller controls a drive motor to output positive and negative torque during vehicle braking, as provided in an embodiment of this application.

[0057] Figure 9 A flowchart illustrating a control method for a drive motor provided in an embodiment of this application;

[0058] Figure 10 A schematic diagram illustrating how to reduce the "nodding" phenomenon during vehicle operation, provided as an embodiment of this application;

[0059] Figure 11 A flowchart of another control method for a drive motor provided in an embodiment of this application. Detailed Implementation

[0060] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. In the description of this application, unless otherwise stated, " / " indicates that the objects before and after are in an "or" relationship. For example, A / B can represent A or B. "And / or" in this application is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone, where A and B can be singular or plural. Furthermore, in the description of this application, unless otherwise stated, "multiple" refers to two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple. Furthermore, to facilitate a clear description of the technical solutions in the embodiments of this application, the terms "first" and "second" are used in the embodiments of this application to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that "first" and "second" are not necessarily different. Meanwhile, in the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is being used as an example, illustration, or description. Any embodiment or design scheme described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of terms such as "exemplary" or "for example" is intended to present related concepts in a concrete manner for ease of understanding.

[0061] Vehicle "nodding" typically refers to the phenomenon where the front of a vehicle dips down and the rear rises up when braking, resembling a "nodding" motion. This phenomenon is related to factors such as the vehicle's suspension system, brake distribution, and weight transfer.

[0062] This application provides a control method for a drive motor, applicable to various vehicles, specifically those equipped with braking control functions. For example, the vehicle may be equipped with a drive system and a braking system. The drive system drives the vehicle via a motor. The braking system uses a hydraulic or mechanical system to achieve real-time adjustment of the suspension vertical force. Furthermore, all vehicle devices, such as lights, windows, door locks, rearview mirrors, audio-visual systems, and horns, are interconnected via a network. The vehicle also features a reversing camera or reversing radar, automatic braking, automatic steering, and vehicle assistance systems. The control method for the vehicle's drive motor can be configured to be implemented through the vehicle's main controller or an independent controller, without specific limitations. This application does not limit the specific type or structure of the vehicle. One possible vehicle structure is described below.

[0063] Taking electric vehicles as an example, (attached) Figure 1 A possible structure of vehicle 01 is shown. Vehicle 01 may include a drive system 10, a battery 20, a braking system 30, and wheels 40. Wheels 40 include front wheels 41 and rear wheels 42. Battery 20 provides electrical energy to drive system 10 and braking system 30. Drive system 10 and braking system 30 are respectively connected to the front wheels 41 and rear wheels 42 in a drive transmission. Drive system 10 receives power from battery 20 and provides driving torque or braking torque to vehicle 01. Braking system 30 receives power from battery 20 and provides braking torque to vehicle 01.

[0064] The operating states of vehicle 01 include driving state and braking state. Driving state refers to the state where the drive system 10 of vehicle 01 converts the DC power from battery 20 into three-phase AC power and supplies power to drive motor 12, causing drive motor 12 to output positive torque and rotate forward, thereby driving wheels 40 to rotate forward, thus propelling vehicle 01 forward. Braking state refers to the state where the braking system 30 of vehicle 01 outputs braking torque to wheels 40, causing vehicle 01's speed to gradually decrease. Simultaneously, drive motor 12 of vehicle 01 can also output negative torque. Specifically, drive system 10 of vehicle 01 converts the DC power from battery 20 into three-phase AC power with any two phases swapped to counteract the induced current generated by drive motor 12 following the forward rotation of wheels 40, and supplies power to drive motor 12, causing drive motor 12 to output negative torque, providing braking torque to wheels 40, thus reducing vehicle 01's speed under the action of braking torque. Here, positive torque output by drive motor 12 means that the direction of the torque output by drive motor 12 is the same as the direction of rotation of drive motor 12. The negative torque output of drive motor 12 means that the direction of the torque output by drive motor 12 is opposite to the direction of rotation of drive motor 12.

[0065] Appendix Figure 2 One possible structure of the drive system 10 is shown. The drive system 10 includes a motor controller 11 and a drive motor 12. The drive motor 12 is driven by the wheels 40, specifically by the front wheels 41 and the rear wheels 42, and is used to drive the front wheels 41 and the rear wheels 42 to rotate. The drive motor 12 is connected to the motor controller 11, which controls the output of positive or negative torque by the drive motor 12. For example, during the driving of the vehicle 01, the motor controller 11 converts the DC power from the battery 20 into three-phase AC power, which is used to drive the drive motor 12 to output positive torque.

[0066] Appendix Figure 3 A possible structure of the motor controller 11 is shown. The motor controller 11 includes a processor 110, a memory 120, and a sensor module 130, etc. The memory 120 includes an external memory interface 1201 and an internal memory 1202.

[0067] It is understood that the structures illustrated in the embodiments of this application do not constitute a specific limitation on vehicle 01. In other embodiments of this application, vehicle 01 may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0068] Processor 110 may include one or more processing units, such as: a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), a system-on-chip (SoC), a central processing unit (CPU), an application processor (AP), a network processor (NP), a digital signal processor (DSP), a microcontroller unit (MCU), a programmable logic device (PLD), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a video codec, and a neural network processing unit (NPU), etc. Different processing units may be independent devices or integrated into one or more processors. For example, processor 110 may be an application processor (AP). Alternatively, processor 110 may be integrated into a system-on-chip (SoC). Or, processor 110 may be integrated into an integrated circuit (IC) chip. The processor 110 may include an analog front end (AFE) and a micro-controller unit (MCU) in an IC chip.

[0069] The processor 110 may also include a memory for storing computer instructions and data. In some embodiments, the memory in the processor 110 is a cache memory. This memory can store computer instructions or data that the processor 110 has just used or that are used repeatedly. If the processor 110 needs to use the computer instructions or data again, it can retrieve them directly from the memory. This avoids repeated accesses, reduces the waiting time of the processor 110, and thus improves the efficiency of the system.

[0070] In some embodiments, the processor 110 may include one or more interfaces. Interfaces may include an inter-integrated circuit (I2C) interface, an inter-integrated circuit sound (I2S) interface, a pulse code modulation (PCM) interface, a universal asynchronous receiver / transmitter (UART) interface, a mobile industry processor interface (MIPI), a general-purpose input / output (GPIO) interface, a subscriber identity module (SIM) interface, and / or a USB interface, etc.

[0071] In some embodiments, the processor may be a processor or controller, such as a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute the various exemplary logic blocks, modules, and circuits described in connection with this disclosure. The processor described above may also be a combination that implements computational functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0072] The processor 110 can be coupled to the sensor module 130, and the processor 110 can process the sensor data.

[0073] It is understood that the interface connection relationships between the modules illustrated in the embodiments of this application are merely illustrative and do not constitute a structural limitation on vehicle 01. In other embodiments of this application, vehicle 01 may also adopt different interface connection methods or a combination of multiple interface connection methods.

[0074] The external storage interface 1201 can be used to connect an external memory card, such as a micro SanDisk (Micro SD) card, to expand the storage capacity of the vehicle 01. The external memory card communicates with the processor 110 through the external storage interface 1201 to perform data storage functions. For example, music, video, and other files can be saved on the external memory card.

[0075] Internal memory 1202 can be used to store computer executable program code, which includes computer instructions. Processor 110 executes various functional applications and data processing of vehicle 01 by running the computer instructions stored in internal memory 1202. For example, internal memory 1202 and processor 110 can be coupled together via a bus. This bus can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The aforementioned bus can be categorized as an address bus, data bus, control bus, etc.

[0076] In this embodiment of the application, when the computer instructions are executed by the processor 110, the vehicle 01 executes the drive motor control method in this embodiment of the application.

[0077] In addition, the internal memory 1202 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, universal flash storage (UFS), etc.

[0078] The memory involved in the embodiments of this application can be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SLDRAM), and direct rambus RAM (DR RAM). It should be noted that the memory used in the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0079] In related technologies, the vehicle body and chassis are non-rigidly connected via a suspension. During vehicle braking, the vehicle body compresses the suspension due to inertia, causing a pitching phenomenon, or "nose-diving," where the front of the vehicle dips and the rear rises. Subsequently, after the vehicle stops, the vehicle body loses its inertia, and the elastic potential energy of the compressed suspension is released, causing a pitching phenomenon, or "heel-lift," where the front of the vehicle rises and the rear pulls back. Thus, during vehicle braking, passengers inside the vehicle experience noticeable back-and-forth swaying, affecting comfort.

[0080] Currently, some "comfort braking" functions have been proposed. While these can improve the "nose-diving" phenomenon, their effectiveness is limited or they may affect the lifespan of the hydraulic valve body. For example, "comfort braking" functions that reduce the braking torque of the brake pedal or control the positive torque output of the drive motor to reduce negative torque, while improving the "nose-diving" phenomenon, will increase the braking distance. Similarly, "comfort braking" functions that adjust the ratio of hydraulic braking torque between the front and rear wheel brakes require frequent opening and closing of valves on the hydraulic valve lines, thus affecting the lifespan of the hydraulic valve body.

[0081] Therefore, this application provides a control method for a drive motor, a motor controller, a drive system, and a vehicle. In this drive motor control method, the motor controller can, when the vehicle is braking and the vehicle speed is greater than or equal to a second threshold and less than or equal to a first threshold, control the first drive motor used to drive the front wheels to output positive torque. Since the braking torque acting on the front wheels is the sum of the positive torque output by the first drive motor and the hydraulic braking torque output by the brake, and the positive torque output by the first drive motor is in the opposite direction to the hydraulic braking torque output by the brake, outputting positive torque by the first drive motor can reduce the braking torque acting on the front wheels. Furthermore, the second drive motor used to drive the rear wheels is controlled to output a first negative torque. Similarly, since the braking torque acting on the front wheels is the sum of the first negative torque output by the first drive motor and the hydraulic braking torque output by the brake, and the first negative torque output by the first drive motor is in the same direction as the hydraulic braking torque output by the brake, outputting first negative torque by the first drive motor can increase the braking torque acting on the rear wheels. This shifts the vehicle's center of gravity rearward, reducing the compression of the suspension due to inertia and the forward and backward swaying during braking. Therefore, by dynamically adjusting the torque output of the front wheel motor (first drive motor) and the rear wheel motor (second drive motor), vehicle pitching and swaying can be reduced, improving comfort without affecting the lifespan of the hydraulic valve body or the braking distance.

[0082] The drive motor control method, motor controller, drive system, and vehicle provided in this application embodiment can be as shown in the appendix. Figure 3 The motor controller 11 is shown. The vehicle can be as shown in the attached diagram. Figure 1 The vehicle 01 shown is illustrated in this application embodiment. Taking the vehicle 01 including a drive system 10, and the drive system 10 including a motor controller 11 as an example, the drive system 10 of this application will be specifically described.

[0083] For example, see attached Figure 4 As shown, the drive system 10 includes a motor controller 11 and a drive motor 12. The motor controller 11 includes a first motor controller 111 and a second motor controller 112, and the drive motor 12 includes a first drive motor 121 and a second drive motor 122. The first drive motor 121 is connected to the front wheel 41 and drives the front wheel 41. The second drive motor 122 is connected to the rear wheel 42 and drives the rear wheel 42. The first motor controller 111 is connected to the first drive motor 121 and controls the output torque of the first drive motor 121. The second motor controller 112 is connected to the second drive motor 122 and controls the output torque of the second drive motor 122.

[0084] For example, see attached Figure 5 - Appendix Figure 6 The diagram shown is a schematic representation of the first motor controller 111 (or the second motor controller 112) provided in an embodiment of this application. (See attached diagram.) Figure 5 - Appendix Figure 6 As shown, the first motor controller 111 (or the second motor controller 112) is connected to the battery 20 and the first drive motor 121 (or the second drive motor 122).

[0085] For example, see attached Figure 5 As shown, the first motor controller 111 includes a first control device 1111 and a first inverter circuit 1112. The first inverter circuit 1112 includes three switching transistor bridge arms, for example, a first switching transistor bridge arm, a second switching transistor bridge arm, and a third switching transistor bridge arm, and switching transistors Q1, Q2, Q3, Q4, Q5, and Q6. Each switching transistor bridge arm includes an upper bridge arm and a lower bridge arm. Both ends of each switching transistor bridge arm are used to connect to the battery 20, and the midpoint of each switching transistor bridge arm is used to connect to one phase winding of the first drive motor 121. For example, the first switching transistor bridge arm includes an upper bridge arm with switching transistor Q1 and a lower bridge arm with switching transistor Q2. Both ends of the first switching transistor bridge arm are used to connect to the battery 20, and the midpoint of the first switching transistor bridge arm is used to connect to the U-phase winding of the first drive motor 121. The second switching arm includes a switching transistor Q3 in the upper arm and a switching transistor Q4 in the lower arm. Both ends of the second switching arm are used to connect to the battery 20, and the midpoint of the second switching arm is used to connect to the V-phase winding of the first drive motor 121. The third switching arm includes a switching transistor Q5 in the upper arm and a switching transistor Q6 in the lower arm. Both ends of the third switching arm are used to connect to the battery 20, and the midpoint of the third switching arm is used to connect to the W-phase winding of the first drive motor 121.

[0086] For example, see attached Figure 6As shown, the second motor controller 112 includes a second control device 1121 and a second inverter circuit 1122. The second inverter circuit 1122 includes three switching transistor bridge arms, for example, a fourth switching transistor bridge arm, a fifth switching transistor bridge arm, and a sixth switching transistor bridge arm, with switching transistors Q7, Q8, Q9, Q10, Q11, and Q12. Each switching transistor bridge arm includes an upper bridge arm and a lower bridge arm, with both ends of each bridge arm used to connect to the battery 20, and the midpoint of each bridge arm used to connect to one phase winding of the second drive motor 122. For example, the fourth switching transistor bridge arm includes an upper bridge arm with switching transistor Q7 and a lower bridge arm with switching transistor Q8, with both ends of the fourth switching transistor bridge arm used to connect to the battery 20, and the midpoint of the fourth switching transistor bridge arm used to connect to the U-phase winding of the second drive motor 122. The fifth switching bridge arm includes a switching transistor Q9 in the upper bridge arm and a switching transistor Q10 in the lower bridge arm. Both ends of the fifth switching bridge arm are used to connect to the battery 20, and the midpoint of the fifth switching bridge arm is used to connect to the V-phase winding of the second drive motor 122. The sixth switching bridge arm includes a switching transistor Q11 in the upper bridge arm and a switching transistor Q12 in the lower bridge arm. Both ends of the sixth switching bridge arm are used to connect to the battery 20, and the midpoint of the sixth switching bridge arm is used to connect to the W-phase winding of the second drive motor 122.

[0087] As previously mentioned, the motor controller 11 can be used to control the drive motor 12 to output positive or negative torque. When the motor controller 11 controls the drive motor 12 to output positive torque, during the driving process of vehicle 01, the motor controller 11 converts the DC power from battery 20 into three-phase AC power, which is used to drive the drive motor 12 to output positive torque. The drive motor 12 is connected to the wheels 40 of vehicle 01, and the positive torque output by the drive motor 12 is transmitted to the wheels 40 to drive them to rotate forward. When the motor controller 11 controls the drive motor 12 to output negative torque, during the driving process of vehicle 01, the motor controller 11 converts the DC power from battery 20 into three-phase AC power with any two phases swapped to counteract the induced current generated by the drive motor 12 following the forward rotation of the wheels 40, and supplies power to the drive motor 12, causing it to output negative torque. The negative torque output by the drive motor 12 is transmitted to the wheels 40 to provide braking torque, thereby reducing the speed of vehicle 01 under the action of the braking torque.

[0088] When the motor controller 11 controls the drive motor 12 to output positive torque:

[0089] For example, see attached Figure 5As shown, the positive terminal of battery 20 is connected to one end of the first drive motor 121 via the switches Q1, Q3, and Q5 of the upper arm of the first inverter circuit 1112. The other end of the first drive motor 121 is connected to the negative terminal of battery 20 via the switches Q2, Q4, and Q6 of the lower arm of the first inverter circuit 1112. The first inverter circuit 1112 converts the DC power from battery 20 into three-phase AC power and supplies power to the first drive motor 121, causing the first drive motor 121 to output positive torque and drive it to rotate forward. The switches Q1, Q3, and Q5 of the upper arm of the three arms of the first inverter circuit 1112, and the corresponding switches Q2, Q4, and Q6 of the lower arm are alternately turned on. At this time, the direction of the torque output by the first drive motor 121 is the same as the direction of rotation of the first drive motor 121, providing driving torque to the front wheel 41 of vehicle 01.

[0090] In one possible implementation, exemplarily, as shown in the appendix. Figure 5 As shown, the positive terminal of battery 20 can also be connected to the first terminal of the first capacitor C1, and the negative terminal of battery 20 can also be connected to the second terminal of the first capacitor C1. The first capacitor C1 is used to isolate the DC power output from battery 20 before it is input into the first inverter circuit 1112.

[0091] For example, see attached Figure 6 As shown, the positive terminal of battery 20 is connected to one end of the second drive motor 122 via the switches Q7, Q9, and Q11 of the upper arm of the second inverter circuit 1122. The other end of the second drive motor 122 is connected to the negative terminal of battery 20 via the switches Q8, Q10, and Q12 of the lower arm of the second inverter circuit 1122. The second inverter circuit 1122 converts the DC power from battery 20 into three-phase AC power and supplies power to the second drive motor 122, causing the second drive motor 122 to output positive torque and drive it to rotate forward. The switches Q7, Q9, and Q11 of the upper arm of the three arms of the second inverter circuit 1122, and the corresponding switches Q8, Q10, and Q12 of the lower arm are alternately turned on. At this time, the torque output by the second drive motor 122 is in the same direction as the rotation direction of the second drive motor 122, providing driving torque to the rear wheel 42 of the vehicle 01.

[0092] In one possible implementation, similarly, exemplary, as shown in the appendix. Figure 6 As shown, the positive terminal of battery 20 can also be connected to the first terminal of the second capacitor C2, and the negative terminal of battery 20 can also be connected to the second terminal of the second capacitor C2. The second capacitor C2 is used to isolate the DC power output from battery 20 before it is input into the second inverter circuit 1122.

[0093] When the motor controller 11 controls the drive motor 12 to output negative torque:

[0094] For example, see attached Figure 5 As shown, the positive terminal of battery 20 is connected to one end of the first drive motor 121 through the switches Q1, Q2, and Q3 of the upper arm of the first inverter circuit 1112, and the other end of the first drive motor 121 is connected to the negative terminal of battery 20 through the switches Q2, Q4, and Q6 of the lower arm of the first inverter circuit 1112. The first inverter circuit 1112 is used to convert the DC power from battery 20 into three-phase AC power with arbitrary two-phase phase sequence swapping to counteract the induced current generated by the first drive motor 121 following the forward rotation of the front wheel 41, and to supply power to the first drive motor 121, causing the first drive motor 121 to output negative torque. The upper arm switches Q1, Q2, and Q3 and the corresponding lower arm switches Q2, Q4, and Q6 of the three arms of the first inverter circuit 1112 are alternately turned on. At this time, since the front wheel 41 of vehicle 01 and the first drive motor 121 rotate in the same direction, which is still the direction of rotation when driving (i.e., forward rotation), and the torque output by the first drive motor 121 is opposite to the direction of rotation of the first drive motor 121, the torque output by the first drive motor 121 provides braking torque for the front wheel 41 of vehicle 01.

[0095] For example, see attached Figure 6 As shown, the positive terminal of battery 20 is connected to one end of the second drive motor 122 via the switches Q7, Q9, and Q11 of the upper arm of the second inverter circuit 1122. The other end of the second drive motor 122 is connected to the negative terminal of battery 20 via the switches Q8, Q10, and Q12 of the lower arm of the second inverter circuit 1122. The second inverter circuit 1122 converts the DC power from battery 20 into three-phase AC power with arbitrary two-phase phase sequence swapping to counteract the induced current generated by the second drive motor 122 following the forward rotation of the rear wheel 42, and to supply power to the second drive motor 122, causing the second drive motor 122 to output negative torque. The switches Q7, Q9, and Q11 of the upper arm and the corresponding switches Q8, Q10, and Q12 of the lower arm of the three switches of the second inverter circuit 1122 are alternately turned on. At this time, since the rear wheel 42 of vehicle 01 and the second drive motor 122 rotate in the same direction, they are still rotating in the same direction as when in driving mode (i.e., forward rotation). The torque output by the second drive motor 122 is opposite to the rotation direction of the second drive motor 122. Therefore, the torque output by the second drive motor 122 provides braking torque to the rear wheel 42 of vehicle 01.

[0096] In one possible implementation, the first drive motor 121 and the second drive motor 122 can be either three-phase motors or six-phase motors, and this application embodiment does not limit this.

[0097] In this embodiment, the first drive motor 121 and the second drive motor 122 are three-phase AC motors. Both the first drive motor 121 and the second drive motor 122 include three-phase windings. The first inverter circuit 1112 of the first motor controller 111 and the second inverter circuit 1122 of the second motor controller 112 each include three parallel bridge arms. The midpoint of the three bridge arms of the first inverter circuit 1112 is used to connect to the three-phase windings of the first drive motor 121. The midpoint of the three bridge arms of the second inverter circuit 1122 is used to connect to the three-phase windings of the second drive motor 122.

[0098] The first control device 1111 and the second control device 1121 are both modules with computing capabilities, and are respectively the control parts (i.e., processors 110) of the first motor controller 111 and the second motor controller 112. The contents of the processor 110 have been described in detail above, and will not be repeated here.

[0099] In one possible implementation, the structures of the first control device 1111 and the second control device 1121 may be the same or different, and the embodiments of this application do not limit this.

[0100] In one possible implementation, the first control device 1111 and the second control device 1121 can be connected to a communication bus. For example, the first control device 1111 and the second control device 1121 can include a communication terminal that can be connected to the communication bus. The first control device 1111 and the second control device 1121 can establish communication with other components in the vehicle 01 through the communication bus, that is, the first control device 1111 and the second control device 1121 can directly receive signals through the communication bus. For example, they can receive one or more of the following: vehicle speed, torque signal, and braking signal. Furthermore, the first control device 1111 and the second control device 1121 can also send signals to the communication bus. For example, the first control device 1111 sends one or more of the following signals to the communication bus: the output torque of the first drive motor 121 or the current of the first inverter circuit 1112. Exemplarily, the communication bus can be a controller area network (CAN) bus, such as the chassis CAN bus of the vehicle 01. The first control device 1111 is used to control the first drive motor 121, and the second control device 1121 is used to control the second drive motor 122.

[0101] In one possible implementation, the first control device 1111 and the second control device 1121 can be connected to a speed detection device. For example, the first control device 1111 and the second control device 1121 include input terminals for receiving signals from sensors, and these input terminals can be connected to the speed detection device. The speed detection device can be installed on the first drive motor 121 and the second drive motor 122 (e.g., on the rotors of the first drive motor 121 and the second drive motor 122). In this case, the first control device 1111 and the second control device 1121 can receive resolver signals or speed signals from the first drive motor 121 and the second drive motor 122 from the speed detection device. Exemplarily, the speed detection device can be a rotation sensor, a motor speed sensor, etc. A rotation sensor is used to detect the speed and rotor position of the drive motor 12. A motor speed sensor is used to detect the speed of the drive motor 12. Exemplarily, the drive system 10 also includes this rotation sensor. Similarly, the first control device 1111 controls the first drive motor 121, and the second control device 1121 controls the second drive motor 122.

[0102] In one possible implementation, the first control device 1111 and the second control device 1121 can determine the vehicle speed, acceleration (or deceleration), etc., of the vehicle 01 based on the resolver signals of the first drive motor 121 and the second drive motor 122. Alternatively, the rotational speed of the drive motor 12 can be determined based on the rotational speed signals of the first drive motor 121 and the second drive motor 122. This application embodiment does not limit this aspect. Similarly, the first control device 1111 is used to control the first drive motor 121, and the second control device 1121 is used to control the second drive motor 122.

[0103] The vehicle 01 also includes a braking system 30, which is connected to the wheels 40 in a transmission manner. The braking system 30 is used to provide braking torque to the vehicle 01 when the vehicle 01 is in a braking state. This application embodiment takes the vehicle 01 including the braking system 30 as an example to specifically describe the braking system 30 of this application.

[0104] For example, see attached Figure 7 The diagram shown is a schematic representation of the braking system 30 provided in an embodiment of this application. (See attached diagram.) Figure 7As shown, the braking system 30 includes a brake pedal 31, a brake controller 32, and four brakes 33. When the driver depresses the brake pedal 31, the brake controller 32 generates a braking control signal based on the travel of the brake pedal 31. The four brakes 33, according to the braking control signal, output braking torque to the corresponding wheels 40 to reduce the speed of the vehicle 01. During the braking process of the vehicle 01, the greater the travel of the brake pedal 31, the greater the braking torque indicated by the braking signal, the greater the braking torque output by the four brakes 33, and the faster the vehicle 01 decreases in speed.

[0105] In this embodiment, the brake 33 of the brake pedal 31 is a hydraulic system, and the braking torque of the brake 33 refers to the braking torque output by the hydraulic system. It is understood that when the driver depresses the brake pedal 31, the brake 33 outputs hydraulic braking torque to the corresponding wheel 40, indicating that the vehicle 01 is braking; further details will not be provided later.

[0106] In this embodiment, when vehicle 01 is braking, the drive motor 12 can be controlled by the motor controller 11 to output positive and negative torque. This embodiment uses the example of vehicle 01 braking and the drive motor 12 being controlled by the motor controller 11 to output positive and negative torque as an example to specifically illustrate how the drive motor 12 can be controlled by the motor controller 11 to output positive and negative torque when vehicle 01 is braking.

[0107] In one possible implementation, when vehicle 01 is braking, the gear of vehicle 01 can be in forward gear or reverse gear, and this application embodiment does not limit this.

[0108] When vehicle 01 is in drive, drive system 10 drives wheel 40 to rotate forward. The positive torque output by drive motor 12 refers to the torque that drives wheel 40 to rotate forward, and the negative torque output refers to the torque that drives wheel 40 to rotate in the reverse direction. When vehicle 01 is in reverse, drive system 10 drives wheel 40 to rotate in the reverse direction. The positive torque output by drive motor 12 refers to the torque that drives wheel 40 to rotate in the reverse direction, and the negative torque output refers to the torque that drives wheel 40 to rotate forward. In other words, the torque output by drive motor 12 is relative to the direction of rotation of drive wheel 40. Therefore, in this embodiment, the positive torque output by drive motor 12 refers to the torque in the direction of rotation of drive wheel 40, and the negative torque output by drive motor 12 refers to the torque in the opposite direction of rotation of drive wheel 40, which will not be elaborated further.

[0109] For example, see attached Figure 8 The diagram shown is a schematic representation of how the drive motor 12 outputs positive and negative torque under braking conditions of vehicle 01, as provided in an embodiment of this application. (See attached diagram.) Figure 8 As shown, the brake controller 32 is used to communicate with the first motor controller 111 and the second motor controller 112. When the driver presses the brake pedal 31, the brake controller 32 generates a brake control signal based on the travel of the brake pedal 31 and sends the brake control signal to the first motor controller 111 and / or the second motor controller 112. Based on the brake control signal, the first motor controller 111 and / or the second motor controller 112 control the corresponding first drive motor 121 and / or second drive motor 122 to output positive or negative torque.

[0110] In one possible implementation, the communication between the brake controller 32 and the first motor controller 111 and the second motor controller 112 can be wired or wireless, and this application embodiment does not limit this.

[0111] In one possible implementation, wireless communication can be Bluetooth (BL), near field communication (NFC), or Wi-Fi, and this application embodiment does not limit this.

[0112] When the first drive motor 121 and / or the second drive motor 122 outputs positive torque, for example, as shown in the attached... Figure 5 - Appendix Figure 6 As shown, the first inverter circuit 1112 and / or the second inverter circuit 1122 convert the DC power from the battery 20 into three-phase AC power for the first drive motor 121 and / or the second drive motor 122, supplying power to the first drive motor 121 and / or the second drive motor 122, causing the first drive motor 121 and / or the second drive motor 122 to output positive torque, providing driving torque to the wheels 40 of the vehicle 01. At this time, the direction of the torque output by the first drive motor 121 and / or the second drive motor 122 is the same as the direction of rotation of the first drive motor 121 and / or the second drive motor 122, which can reduce the braking torque acting on the wheels 40. Specifically, the first inverter circuit 1112 is used to convert the DC power from the battery 20 into three-phase AC power for the first drive motor 121, and the second inverter circuit 1122 is used to convert the DC power from the battery 20 into three-phase AC power for the second drive motor 122.

[0113] When the first drive motor 121 and / or the second drive motor 122 outputs negative torque, for example, as shown in the attached... Figure 5 - Appendix Figure 6As shown, the first inverter circuit 1112 and / or the second inverter circuit 1122 convert the DC power from the battery 20 into three-phase AC power with any two phases of the first drive motor 121 and / or the second drive motor 122 alternating in phase sequence. This counteracts the induced current generated by the first drive motor 121 and / or the second drive motor 122 as they rotate forward with the wheel 40, and supplies power to the first drive motor 121 and / or the second drive motor 122, causing them to output negative torque and provide braking torque to the wheel 40 of the vehicle 01. At this time, the direction of the torque output by the first drive motor 121 and / or the second drive motor 122 is opposite to the direction of rotation of the first drive motor 121 and / or the second drive motor 122, which can increase the braking torque acting on the wheel 40 and provide auxiliary braking to the wheel 40. Similarly, the first inverter circuit 1112 is used to convert the DC power from the battery 20 into three-phase AC power with any two phases of the first drive motor 121 swapped, and the second inverter circuit 1122 is used to convert the DC power from the battery 20 into three-phase AC power with any two phases of the second drive motor 122 swapped.

[0114] The drive motor control method provided in this application can be implemented on vehicle 01. This application uses the control function of a drive motor in vehicle 01 as an example to specifically describe the drive motor control method of this application.

[0115] In this embodiment, when vehicle 01 is braking, the drive motor 12 can be controlled by the motor controller 11 to output negative torque, as described above, so that the drive motor 12 is in an "auxiliary braking" state, providing auxiliary braking to the wheel 40. That is, in addition to the hydraulic braking torque provided by the brake 33 to the wheel 40, the drive motor 12 also provides braking torque to the wheel 40. Alternatively, the drive motor 12 can be controlled by the motor controller 11 to output a preset torque, so that the drive motor 12 is in a "zero torque control" state, meaning that the hydraulic braking torque is entirely provided by the brake 33 to the wheel 40. Therefore, when vehicle 01 is braking, the drive motor 12 has two states: 1) The drive motor 12 is in a "zero torque control" state, outputting a preset torque to only offset the gear backlash of the drive motor 12, and the hydraulic braking torque is entirely provided by the brake 33 to the wheel 40; 2) The drive motor 12 is in an "auxiliary braking" state, outputting negative torque to provide auxiliary braking to the wheel 40, and the drive motor 12 also provides braking torque to the wheel 40 in addition to the hydraulic braking torque provided by the brake 33.

[0116] In case 1), for example, attached Figure 9 A flowchart illustrating a control method for a drive motor provided in an embodiment of this application is attached. Figure 9 As shown, the method may include steps S901-S907:

[0117] S901, when vehicle 01 is braking, motor controller 11 acquires braking control signal.

[0118] When vehicle 01 brakes, meaning the driver presses the brake pedal 31, the brake controller 32 generates a braking control signal based on the travel of the brake pedal 31 and sends the braking control signal to the motor controller 11. The brake 33, according to the braking control signal, outputs hydraulic braking torque to the corresponding wheel 40 to reduce the speed of vehicle 01. At this time, vehicle 01 will exhibit a "nodding" phenomenon. For example, see attached... Figure 10 As shown in (a), when vehicle 01 brakes, vehicle 01 exhibits a "nodding" phenomenon. The motor controller 11 acquiring the braking control signal means that the motor controller 11 receives the braking control signal from the brake controller 32. Since the motor controller 11 includes a first motor controller 111 and a second motor controller 112, both the first motor controller 111 and the second motor controller 112 receive the braking control signal from the brake controller 32.

[0119] In this embodiment, in response to the driver pressing the brake pedal 31, vehicle 01 begins to decelerate. For example, before the driver presses the brake pedal 31, the vehicle speed is 60 km / h. After the driver presses the brake pedal 31, the vehicle speed decelerates from 60 km / h to 30 km / h after a period of time. S902, the motor controller 11 determines whether the vehicle speed is greater than a first threshold.

[0120] The first threshold is the vehicle speed threshold when prioritizing the braking performance of vehicle 01 without making additional adjustments to the existing braking force distribution between the front and rear wheels. This threshold can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple vehicle speeds when prioritizing the braking performance of vehicle 01 without making additional adjustments to the existing braking force distribution between the front and rear wheels, such as the average, median, or minimum of these speeds. Alternatively, it can be set based on empirical values, such as 10 km / h or 12 km / h.

[0121] In this embodiment of the application, when vehicle 01 is braking, the vehicle speed can be obtained after the motor controller 11 obtains the braking control signal.

[0122] As mentioned above, the motor controller 11 can obtain the vehicle speed through a rotation sensor and a motor wheel speed sensor. In one possible implementation, the rotation sensor and the motor wheel speed sensor can be Hall sensors or magnetoelectric sensors; the types of sensors are not limited in this application embodiment.

[0123] When vehicle 01 is braking, motor controller 11 determines the vehicle speed to decide whether the drive motor 40 needs to provide torque compensation to the front wheels 41 and rear wheels 42, based on the vehicle speed. If the vehicle speed is greater than a first threshold, step S903 is executed. If the vehicle speed is less than or equal to the first threshold, step S904 is executed.

[0124] S903, the first motor controller 111 controls the first drive motor 121 to output a first preset torque, and the second motor controller 112 controls the second drive motor 122 to output a second preset torque.

[0125] The first preset torque is the preload torque to offset the gear backlash of the first drive motor 121, and can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple preload torques that offset the gear backlash of the first drive motor 121, such as the average, median, or minimum value of multiple preload torques that offset the gear backlash of the first drive motor 121; it can also be set based on empirical values, such as 1N or 2N.

[0126] The second preset torque is the preload torque to offset the gear backlash of the second drive motor 122, and can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple preload torques to offset the gear backlash of the second drive motor 122, such as the average, median, or minimum value of multiple preload torques to offset the gear backlash of the second drive motor 122; it can also be set based on empirical values, such as 1N or 2N.

[0127] The first and second preset torques are insufficient to accelerate or decelerate the vehicle 01; they simply cancel each other out. The preload torque of the gear gap between the first drive motor 121 and the second drive motor 122 allows the meshing gear teeth to fit together, eliminating mechanical backlash. This allows the torque output by the corresponding first drive motor 121 and second drive motor 122 to transition very smoothly and continuously from no torque to high torque, avoiding impact caused by gear meshing.

[0128] Understandably, when the first drive motor 121 outputs the first preset torque, it indicates that the first preset torque output by the first drive motor 121 exactly cancels out the preload torque of the gear backlash of the first drive motor 121. At this time, the first drive motor 121 is in a "zero torque control" state. When the second drive motor 122 outputs the second preset torque, it indicates that the second preset torque output by the second drive motor 122 exactly cancels out the preload torque of the gear backlash of the second drive motor 122. At this time, the second drive motor 122 is in a "zero torque control" state.

[0129] In this embodiment, the first threshold is 10 km / h or 12 km / h. When the vehicle speed is greater than the first threshold, it actually corresponds to a range of vehicle speeds greater than the first threshold, for example, vehicle speed > 10 km / h or vehicle speed > 12 km / h.

[0130] When the vehicle speed exceeds a first threshold (e.g., 30 km / h), it indicates a high speed. A larger braking torque is required to brake vehicle 01. If drive motor 12 compensates for torque on wheels 40, the high speed might cause additional adjustments to the existing braking force distribution between the front and rear wheels, affecting the normal driving performance of vehicle 01. Therefore, drive motor 12 does not need to compensate for torque on the front wheels 41 and rear wheels 42. This avoids the need for additional adjustments to the existing braking force distribution between the front and rear wheels at high speeds, thus preventing any impact on the normal driving performance of vehicle 01. In this state, drive motor 12 can be in "zero torque control," where the torque output by drive motor 12 only offsets the preload torque of the gear backlash, with the brake 33 providing the hydraulic braking torque to wheels 40. In other words, the first motor controller 111 controls the first drive motor 121 to output a first preset torque, and the second motor controller 112 controls the second drive motor 122 to output a second preset torque.

[0131] S904, the motor controller 11 determines whether the vehicle speed is less than the second threshold.

[0132] The second threshold is the vehicle speed threshold that might occur when the additional anti-dive torque output by the drive motor 12 is not promptly removed when vehicle 01 is nearly stopped, potentially causing vehicle 01 to crouch backward. This threshold can be set according to actual needs. For example, it can be obtained by statistically analyzing the multiple vehicle speeds that might occur when the additional anti-dive torque output by the drive motor 12 is not promptly removed when vehicle 01 is nearly stopped, such as the average, median, or minimum of these multiple speeds. Alternatively, it can be set based on empirical values, such as 1 km / h or 1.5 km / h.

[0133] In this embodiment, after the motor controller 11 determines that the vehicle speed is less than or equal to a first threshold, it further determines whether the vehicle speed is less than a second threshold. The motor controller 11 further determines whether the vehicle speed is less than the second threshold in order to, when the vehicle 01 is braking, determine whether the drive motor 12 needs to perform torque compensation on the front wheels 41 and the rear wheels 42 based on the vehicle speed. If the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold, step S905 is executed. If the vehicle speed is less than the second threshold, step S903 is executed.

[0134] In this embodiment, the second threshold is 1 km / h or 1.5 km / h. When the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold, this actually corresponds to a speed range greater than or equal to the second threshold and less than or equal to the first threshold, for example, 1 km / h <= vehicle speed <= 10 km / h or 1.5 km / h <= vehicle speed <= 12 km / h. When the vehicle speed is less than the second threshold, this actually corresponds to a speed range less than the second threshold, for example, vehicle speed < 1 km / h or vehicle speed < 1.5 km / h.

[0135] When the vehicle speed is less than the second threshold (e.g., 0.5 km / h), indicating extremely low speed, the "nodding" phenomenon of vehicle 01 is essentially eliminated after the drive motor 12 performs torque compensation on the front wheel 41 and rear wheel 42 when the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold. For example, see attached... Figure 10 As shown in (c), when the vehicle speed is less than the second threshold (e.g., 0.5 km / h), the "nodding" phenomenon of vehicle 01 basically disappears. At this time, if the drive motor 12 continues to compensate for torque to the front wheel 41 and the rear wheel 42, the additional anti-nodding torque output by the drive motor 12 may cause vehicle 01 to lurch backward when vehicle 01 is almost stopped because the additional anti-nodding torque output by the drive motor 12 is not removed in time. Therefore, the motor controller 11 can control the drive motor 12 to exit the torque compensation for the front wheel 41 and the rear wheel 42, and return to the "zero torque control" state, executing step S903. At this time, the drive motor 12 can be in the "zero torque control" state, only offsetting the preload torque of the gear backlash of the drive motor 12, and the hydraulic braking torque is entirely provided to the wheel 40 by the brake 33. That is, the first motor controller 111 controls the first drive motor 121 to output the first preset torque, and the second motor controller 112 controls the second drive motor 122 to output the second preset torque. In this way, when the "nodding" phenomenon of vehicle 01 has basically disappeared, the motor controller 11 can control the drive motor 12 to disengage the torque compensation to the front wheel 41 and the rear wheel 42, and brake through the hydraulic braking torque of the brake 33. In this way, when vehicle 01 is almost stopped, it can avoid the additional anti-nodding torque of drive motor 12 not being removed in time, which would cause vehicle 01 to sag backward, thereby reducing the front and rear sway of vehicle 01, improving comfort, and not affecting the life of hydraulic valve body and improving the compensation effect.

[0136] S905, the first motor controller 111 controls the first drive motor 121 to output positive torque, and the second motor controller 112 controls the second drive motor 122 to output first negative torque.

[0137] When the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold (for example, the vehicle speed is 5 km / h), the motor controller 11 can control the drive motor 12 to perform torque compensation on the front wheel 41 and the rear wheel 42. That is, the first motor controller 111 controls the first drive motor 121 to output positive torque, and the second motor controller 112 controls the second drive motor 122 to output the first negative torque.

[0138] In this embodiment, when vehicle 01 brakes, vehicle 01 will still move forward, and the rotation direction of wheels 40 and drive motor 12 will still be positive. However, the vehicle speed will decrease rapidly due to the hydraulic braking torque of brake 33, and vehicle 01 will be in a deceleration state. Since the vehicle speed can only change from high to low when vehicle 01 is in a deceleration state, the prior state of vehicle 01 is that the vehicle speed is greater than the first threshold. The vehicle speed is relatively high, and torque compensation for the front wheels 41 and rear wheels 42 can be eliminated through drive motor 12, making the braking effect more obvious. This avoids additional adjustments to the existing braking force distribution of the front and rear wheels by the torque output of drive motor 12 at high vehicle speeds, which would affect the performance of vehicle 01 during normal driving. At this time, drive motor 12 is in a "zero torque control" state. The first motor controller 111 controls the first drive motor 121 to output a first preset torque, and the second motor controller 112 controls the second drive motor 122 to output a second preset torque. When the vehicle speed decreases to a level greater than or equal to the second threshold and less than or equal to the first threshold, the motor controller 11 can perform torque compensation on the front wheels 41 and rear wheels 42 through the drive motor 12. Specifically, the first motor controller 111 controls the first drive motor 121 to output positive torque, reducing the braking torque acting on the front wheels 41. The second motor controller 112 controls the second drive motor 122 to output a first negative torque, increasing the braking torque acting on the rear wheels 42. This shifts the center of gravity of the vehicle 01 rearward, thereby reducing the compression of the suspension due to inertia and the forward and backward swaying of the vehicle 01 during braking. For example, see attached... Figure 10 As shown in (b), after torque compensation is performed on the front wheels 41 and rear wheels 42 by the drive motor 12, i.e., the first motor controller 111 controls the first drive motor 121 to output positive torque and the second motor controller 112 controls the second drive motor 122 to output a first negative torque, the center of gravity of the vehicle 01 shifts rearward, reducing the "nodding" and back-and-forth swaying of the vehicle 01 and improving comfort. Therefore, by dynamically adjusting the torque output by the front wheel motor (i.e., the first drive motor 121) and the rear wheel motor (the second drive motor 122), the "nodding" and back-and-forth swaying of the vehicle 01 can be reduced, improving comfort without affecting the life of the hydraulic valve body and improving the compensation effect.

[0139] In one possible implementation, when the vehicle speed is less than a first threshold, the positive torque output by the first drive motor 121 is less than or equal to the braking torque of the brake 33 of the front wheel 41.

[0140] Understandably, when the vehicle speed is less than the first threshold, the positive torque output by the first drive motor 121 is less than or equal to the hydraulic braking torque of the brake 33 of the front wheel 41. In other words, the positive torque used to reduce the braking torque acting on the front wheel 41 cannot be greater than the hydraulic braking torque of the brake 33 of the front wheel 41. Otherwise, it will violate the driver's intention to decelerate and instead accelerate or maintain a constant speed, resulting in a significant increase in braking distance or even complete failure, causing a great safety hazard.

[0141] In one possible implementation, the first compensation torque is the difference between a positive torque and a first preset torque; the second compensation torque is the difference between a first negative torque and a second preset torque.

[0142] The first compensation torque is the compensation torque of the first drive motor 121 from the initial torque to the target torque, that is, the difference between the positive torque and the first preset torque. The second compensation torque is the compensation torque of the second drive motor 122 from the initial torque to the target torque, that is, the difference between the first negative torque and the second preset torque. The compensation torque between the initial torque and the target torque (i.e., the difference between the target torque and the initial torque) is the difference in torque values ​​between the target torque and the initial torque when the initial torque and the target torque are in the same direction; when the initial torque and the first target torque are in opposite directions, it is the sum of the torque values ​​between the target torque and the initial torque.

[0143] In one possible implementation, the difference between the first rate at which the first preset torque changes to positive torque and the second rate at which the second preset torque changes to first negative torque is less than or equal to a fourth threshold.

[0144] The fourth threshold is the threshold for the rate difference between the rate at which the first drive motor 121 changes from its initial torque to the target torque and the rate at which the second drive motor 122 changes from its initial torque to the target torque. This threshold can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple rate differences between the first drive motor 121 and the second drive motor 122, such as the mean, median, or minimum of these rate differences. Alternatively, it can be set based on empirical values, such as 0 N·m / s or 0.5 N·m / s.

[0145] In this embodiment of the application, the difference between the first rate at which the first preset torque changes to positive torque and the second rate at which the second preset torque changes to negative torque is less than or equal to a fourth threshold, indicating that the first rate and the second rate are approximately the same.

[0146] Wherein, the first rate is the average rate of change of the torque output by the first drive motor 121 over a period of time, which is the ratio of the torque difference output by the first drive motor 121 to the time difference, and can be expressed by the following formula (1):

[0147] τ1=(T2-T1) / t2-t1 formula (1);

[0148] Wherein, T1 is the torque output by the first drive motor 121 at time t1, T2 is the torque output by the first drive motor 121 at time t2, T1 and T2 are between the positive torque and the first preset torque, and T2>T1; when T1 and T2 are in the same direction, T2-T1 is the difference between the two torque values, and when T1 and T2 are in opposite directions, T2-T1 is the sum of the two torque values; τ1 is the first rate of the torque output by the first drive motor 121 between time t1 and time t2.

[0149] The second rate is the average rate of change of the torque output by the second drive motor 122 over a period of time. It is the ratio of the torque difference output by the second drive motor 122 to the time difference, and can be expressed by the following formula (2):

[0150] τ2=(T4-T3) / t4-t3 Formula (2);

[0151] Wherein, T3 is the torque output by the second drive motor 122 at time t3, T4 is the torque output by the second drive motor 122 at time t4, T3 and T4 are between the second preset torque and the first negative torque, and T4>T3; when T4 and T3 are in the same direction, T4-T3 is the difference between the two torque values, and when T4 and T3 are in opposite directions, T4-T3 is the sum of the two torque values; τ2 is the second rate of the torque output by the second drive motor 122 between time t3 and time t4.

[0152] S906, the motor controller 11 determines whether the front wheel 41 and / or the rear wheel 42 is slipping.

[0153] The motor controller 11 can use sensors to obtain the wheel speed and / or direction of the wheels 40 to determine whether the front wheel 41 and / or rear wheel 42 are slipping. In one possible implementation, the sensor can be a wheel speed sensor or a yaw rate sensor; the type of sensor is not limited in this embodiment. The wheel speed sensor is used to detect the rotational speed of the wheel 40. The yaw rate sensor is used to detect the direction of the wheel 40. It is understood that wheel speed sensors and / or yaw rate sensors can be installed on all four wheels 40 of the vehicle 01.

[0154] In one possible implementation, wheel 40 is determined to be slipping if its wheel speed is greater than a wheel speed threshold; and / or, wheel 40 is determined to be slipping if its directional offset angle is greater than an angle threshold.

[0155] The wheel speed threshold is the threshold value for the wheel speed when the wheel slips at 40°, and it can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple wheel speeds when the wheel slips at 40°, such as the average, median, or minimum value of multiple wheel speeds when the wheel slips at 40°; it can also be set based on empirical values, such as 10 km / h.

[0156] The angle threshold is the threshold for the directional deviation angle when the wheel slips at 40 degrees, and it can be set according to actual needs. For example, it can be obtained by statistically analyzing the directional deviation angles when the wheel slips at 40 degrees, such as the mean, median, or minimum of the directional deviation angles when the wheel slips at 40 degrees; it can also be set based on empirical values, such as 10°.

[0157] When the wheel speed of wheel 40 exceeds the wheel speed threshold, it indicates that the wheel speed of wheel 40 has significantly increased, exceeding the normal driving wheel speed, and it can be determined that wheel 40 is slipping. For example, when vehicle 01 is driving normally, the wheel speed of front wheel 41 is 3 km / h. At a certain moment, the wheel speed of front wheel 41 rapidly increases to 10 km / h, therefore, it can be determined that front wheel 41 is slipping at that moment. When the directional deviation angle of wheel 40 exceeds the angle threshold, it indicates that the direction of wheel 40 has completely deviated, and vehicle 01 has lost control, and it can be determined that wheel 40 is slipping. For example, when vehicle 01 is driving normally, the directional deviation angle of front wheel 41 is 1°. At a certain moment, the directional deviation angle of front wheel 41 suddenly becomes 10°, therefore, it can be determined that front wheel 41 is slipping at that moment.

[0158] In this embodiment of the application, after the motor controller 11 determines that the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold, it further determines whether the front wheel 41 and / or the rear wheel 42 are slipping.

[0159] Since the rotational speed of the corresponding front wheel 41 and / or rear wheel 42 will increase sharply once the front wheel 41 and / or rear wheel 42 slips, the effective torque transmitted to the corresponding front wheel 41 and / or rear wheel 42 will decrease sharply. If the drive motor 12 continues to compensate for torque on the front wheel 41 and rear wheel 42 at this time, it will cause the vehicle 01 to lose control. Therefore, the motor controller 11 further determines whether the front wheel 41 and / or rear wheel 42 is slipping in order to determine whether the drive motor 12 needs to discontinue torque compensation on the front wheel 41 and rear wheel 42 to avoid loss of control of the vehicle 01, thereby ensuring the stability and safety of the vehicle 01. If neither the front wheel 41 nor the rear wheel 42 is slipping, step S905 is executed. If the front wheel 41 and / or rear wheel 42 is slipping, step S907 is executed.

[0160] If neither the front wheel 41 nor the rear wheel 42 slips, it indicates that the drive motor 12 does not need to discontinue torque compensation for the front wheel 41 and the rear wheel 42. At this time, step S905 is executed, and the motor controller 11 continues to control the drive motor 12 to perform torque compensation for the front wheel 41 and the rear wheel 42. That is, the motor controller 11 controls the first drive motor 121 to output positive torque, and the second motor controller 112 controls the second drive motor 122 to output first negative torque.

[0161] S907, the first compensation torque of the first drive motor 121 is reduced to 0 torque at a target rate greater than the third threshold, and the second compensation torque of the second drive motor 122 is reduced to 0 torque.

[0162] The third threshold is the threshold for the rate at which the drive motor 12 rapidly disengages, compensating for the torque of the front wheel 41 and the rear wheel 42. This threshold can be set according to actual needs. For example, it can be obtained by statistically analyzing multiple rates of torque compensation for the front wheel 41 and the rear wheel 42 during rapid disengagement of the drive motor 12, such as the average, median, or minimum of these rates. Alternatively, it can be set based on empirical values, such as 1000 N·m / s or 800 N·m / s.

[0163] It is understandable that reducing the first compensation torque of the first drive motor 121 to zero torque indicates reducing the torque compensation of the first drive motor 121 on the front wheel 41 to zero, that is, discontinuing torque compensation on the front wheel 41. Reducing the second compensation torque of the second drive motor 122 to zero torque indicates reducing the torque compensation of the second drive motor 122 on the rear wheel 42 to zero, that is, discontinuing torque compensation on the rear wheel 42.

[0164] When the front wheel 41 and / or the rear wheel 42 slips, it indicates that the drive motor 12 needs to disengage the torque compensation to the front wheel 41 and the rear wheel 42. The drive motor 12 also needs to disengage the torque compensation to the front wheel 41 and the rear wheel 42 at a relatively fast rate. That is, the first compensation torque of the first drive motor 121 is reduced to 0 torque at a relatively fast rate (i.e., greater than the third threshold), and the second compensation torque of the second drive motor 122 is reduced to 0 torque. This can prevent the vehicle 01 from losing control and ensure the stability and safety of the vehicle 01.

[0165] The drive motor control method described in steps S901-S907 above involves the following steps: First, when vehicle 01 is braking, motor controller 11 acquires a braking control signal. Second, motor controller 11 determines whether the vehicle speed is greater than a first threshold. If the vehicle speed is greater than the first threshold, the first motor controller 111 controls the first drive motor 121 to output a first preset torque, and the second motor controller 112 controls the second drive motor 122 to output a second preset torque. Third, motor controller 11 determines whether the vehicle speed is less than a second threshold. If the vehicle speed is less than the second threshold, the first motor controller 111 controls the first drive motor 121 to output the first preset torque, and the second motor controller 112 controls the second drive motor 122 to output the second preset torque. Finally, if the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold, motor controller 11 determines whether the front wheel 41 and / or the rear wheel 42 is slipping. When the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold, and neither the front wheel 41 nor the rear wheel 42 slips, the motor controller 11 controls the first drive motor 121 to output positive torque to reduce the braking torque acting on the front wheel 41, and the second motor controller 112 controls the second drive motor 122 to output first negative torque to increase the braking torque acting on the rear wheel 42. This shifts the vehicle's center of gravity rearward, thereby reducing the compression of the suspension due to inertia and the front-rear swaying of the vehicle 01 during braking. When the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold, and the front wheel 41 and / or the rear wheel 42 slips, the first compensation torque of the first drive motor 121 is reduced to zero at a target rate greater than the third threshold, and the second compensation torque of the second drive motor 122 is also reduced to zero. This prevents the vehicle 01 from losing control and ensures the stability and safety of the vehicle 01. Therefore, this method allows the motor controller 11 to not only dynamically adjust the torque output of the first drive motor 121 and the second drive motor 122, reducing the "nodding" and back-and-forth swaying of the vehicle 01 and improving comfort, but also to maintain the lifespan of the hydraulic valve body and improve the compensation effect. Furthermore, it can promptly disengage torque compensation for the wheel 40 when the wheel 40 slips, preventing the vehicle 01 from losing control and ensuring the stability and safety of the vehicle 01.

[0166] In the second case, for example, attached Figure 11 A flowchart illustrating a control method for a drive motor provided in an embodiment of this application is attached. Figure 11 As shown, the method may include steps S1101-S1108:

[0167] S1101, when vehicle 01 is braking, motor controller 11 obtains braking control signal.

[0168] Step S1101 is the same as step S901 above, and will not be repeated here.

[0169] S1102, the motor controller 11 determines whether the vehicle speed is greater than the first threshold.

[0170] Step S1102 is the same as step S902 above, and will not be repeated here.

[0171] S1103, the first motor controller 111 controls the first drive motor 121 to output a second negative torque, and the second motor controller 112 controls the second drive motor 122 to output a third negative torque that is less than the first negative torque.

[0172] Understandably, when the first drive motor 121 outputs the first negative torque, it indicates that the first drive motor 121 is performing auxiliary braking on the front wheel 41, and at this time, the first drive motor 121 is in the "auxiliary braking" state. When the second drive motor 122 outputs the third negative torque, it indicates that the second drive motor 122 is performing auxiliary braking on the rear wheel 41, and at this time, the second drive motor 122 is in the "auxiliary braking" state.

[0173] In this embodiment, the third negative torque is less than the first negative torque, indicating that when the second drive motor 122 performs torque compensation on the rear wheel 42, it is done under the premise that the second drive motor 122 performs auxiliary braking on the rear wheel 41.

[0174] When the vehicle speed exceeds the first threshold (e.g., 30 km / h), it indicates a high speed, requiring a larger braking torque to brake vehicle 01. If drive motor 12 compensates for torque on wheels 40, the high speed might necessitate additional adjustments to the existing braking force distribution between the front and rear wheels, impacting the normal driving performance of vehicle 01. Therefore, drive motor 12 does not need to compensate for torque on the front wheels 41 and rear wheels 42. This avoids the need for additional adjustments to the existing braking force distribution between the front and rear wheels at high speeds, thus preventing any impact on the normal driving performance of vehicle 01. In this state, drive motor 12 can operate in "auxiliary braking," outputting negative torque to assist braking of wheels 40. In addition to the hydraulic braking torque provided by brake 33 to wheels 40, drive motor 12 also provides braking torque. In other words, the first motor controller 111 controls the first drive motor 121 to output a second negative torque, and the second motor controller 112 controls the second drive motor 122 to output a third negative torque.

[0175] S1104, the motor controller 11 determines whether the vehicle speed is less than the second threshold.

[0176] Step S1104 is the same as step S904 above, and will not be repeated here.

[0177] S1105, the first motor controller 111 controls the first drive motor 121 to output a first preset torque, and the second motor controller 112 controls the second drive motor 122 to output a second preset torque.

[0178] When the vehicle speed is less than the second threshold (e.g., 0.5 km / h), indicating extremely low speed, and after the drive motor 12 performs torque compensation on the front wheels 41 and rear wheels 42 when the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold, the "nodding" phenomenon of vehicle 01 has basically disappeared. At this time, if the drive motor 12 continues to perform torque compensation on the front wheels 41 and rear wheels 42, when vehicle 01 is almost stopped, the additional anti-nodding torque output by the drive motor 12 may cause vehicle 01 to lurch backward because the additional anti-nodding torque is not removed in time. Therefore, the motor controller 11 can control the drive motor 12 to exit the torque compensation on the front wheels 41 and rear wheels 42 and return to the "zero torque control" state. At this time, the drive motor 12 can be in the "zero torque control" state, only offsetting the preload torque of the gear backlash of the drive motor 12, and the hydraulic braking torque is provided entirely by the brake 33 to the wheels 40. In other words, the first motor controller 111 controls the first drive motor 121 to output a first preset torque, and the second motor controller 112 controls the second drive motor 122 to output a second preset torque.

[0179] S1106, the first motor controller 111 controls the first drive motor 121 to output positive torque, and the second motor controller 112 controls the second drive motor 122 to output first negative torque.

[0180] Step S1106 is largely the same as step S905 above, so it will not be repeated here.

[0181] In one possible implementation, the first compensation torque is the difference between the positive torque and the second negative torque; the second compensation torque is the difference between the first negative torque and the third negative torque.

[0182] The first compensation torque is the compensation torque of the first drive motor 121 from the initial torque to the target torque, that is, the difference between the positive torque and the second negative torque. The second compensation torque is the compensation torque of the second drive motor 122 from the initial torque to the target torque, that is, the difference between the first negative torque and the third negative torque. Similarly, the compensation torque between the initial torque and the target torque (i.e., the difference between the target torque and the initial torque) is the difference between the torque values ​​of the target torque and the initial torque when the initial torque and the target torque are in the same direction; when the initial torque and the first target torque are in opposite directions, it is the sum of the torque values ​​of the target torque and the initial torque.

[0183] In one possible implementation, the difference between the third rate at which the second negative torque changes to positive torque and the fourth rate at which the third negative torque changes to the first negative torque is less than or equal to a fourth threshold.

[0184] The fourth threshold is the same as the fourth threshold in step 905 above, and will not be repeated here.

[0185] Similarly, in the embodiments of this application, the difference between the third rate and the fourth rate is less than or equal to the fourth threshold, indicating that the third rate and the fourth rate are approximately the same.

[0186] The third rate is the average rate of change of the torque output by the first drive motor 121 over a period of time. It is the ratio of the torque difference output by the first drive motor 121 to the time difference, and can be expressed by the following formula (3):

[0187] τ3=(T6-T5) / t6-t5 Formula (3);

[0188] Wherein, T5 is the torque output by the first drive motor 121 at time t5, T6 is the torque output by the first drive motor 121 at time t6, T5 and T6 are between the positive torque and the second negative torque, and T6>T5; when T5 and T6 are in the same direction, T6-T5 is the difference between the two torque values, and when T6 and T5 are in opposite directions, T6-T5 is the sum of the two torque values; τ3 is the third rate of the torque output by the first drive motor 121 between time t5 and time t6.

[0189] The fourth rate is the average rate of change of the torque output by the second drive motor 122 over a period of time. It is the ratio of the torque difference output by the second drive motor 122 to the time difference, and can be expressed by the following formula (4):

[0190] τ4=(T8-T7) / t8-t7 formula (4);

[0191] Wherein, T7 is the torque output by the second drive motor 122 at time t7, T8 is the torque output by the second drive motor 122 at time t8, T7 and T8 are between the third negative torque and the first negative torque, and T8>T7; when T8 and T7 are in the same direction, T8-T7 is the difference between the two torque values, and when T8 and T7 are in opposite directions, T8-T7 is the sum of the two torque values; τ4 is the fourth rate of the torque output by the second drive motor 122 between time t7 and time t8.

[0192] S1107, the motor controller 11 determines whether the front wheel 41 and / or the rear wheel 42 is slipping.

[0193] Step S1107 is the same as step S906 above, and will not be repeated here.

[0194] S1107, reduce the first compensation torque of the first drive motor 121 to 0 torque at a target rate greater than the third threshold, and reduce the second compensation torque of the second drive motor 122 to 0 torque.

[0195] Step S1108 is the same as step S907 above, and will not be repeated here.

[0196] The drive motor control method described in steps S1101-S1108 above involves the following steps: First, when vehicle 01 is braking, motor controller 11 acquires a braking control signal. Second, motor controller 11 determines whether the vehicle speed is greater than a first threshold. If the vehicle speed is greater than the first threshold, first motor controller 111 controls first drive motor 121 to output a second negative torque, and second motor controller 112 controls second drive motor 122 to output a third negative torque. Next, motor controller 11 determines whether the vehicle speed is less than a second threshold. If the vehicle speed is less than the second threshold, first motor controller 111 controls first drive motor 121 to output a first preset torque, and second motor controller 112 controls second drive motor 122 to output a second preset torque. Finally, if the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold, motor controller 11 determines whether the front wheel 41 and / or rear wheel 42 is slipping. When the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold, and neither the front wheel 41 nor the rear wheel 42 slips, the first motor controller 111 controls the first drive motor 121 to output positive torque to reduce the braking torque acting on the front wheel 41, and the second motor controller 112 controls the second drive motor 122 to output first negative torque to increase the braking torque acting on the rear wheel 42. This shifts the vehicle's center of gravity rearward, thereby reducing the compression of the suspension due to inertia and the forward and backward swaying of the vehicle 01 during braking. When the vehicle speed is greater than or equal to the second threshold and less than or equal to the first threshold, and the front wheel 41 and / or the rear wheel 42 slips, the first compensation torque of the first drive motor 121 is reduced to zero at a target rate greater than the third threshold, and the second compensation torque of the second drive motor 122 is also reduced to zero. This prevents the vehicle 01 from losing control and ensures the stability and safety of the vehicle 01. Therefore, this method can not only reduce the "nodding" and back-and-forth swaying of vehicle 01 and improve comfort by dynamically adjusting the torque output of the first drive motor 121 and the second drive motor 122, but also does not affect the life of the hydraulic valve body and improve the compensation effect. Furthermore, it can promptly disengage torque compensation for wheel 40 when wheel 40 slips, preventing vehicle 01 from losing control and ensuring the stability and safety of vehicle 01.

[0197] This application provides a control method for a drive motor, a motor controller, a drive system, and a vehicle. When the vehicle is braking, and the vehicle speed is greater than or equal to a second threshold and less than or equal to a first threshold, the motor controller controls a first drive motor for driving the front wheels to output positive torque. Since the braking torque acting on the front wheels is the sum of the positive torque output by the first drive motor and the hydraulic braking torque output by the brake, and the positive torque output by the first drive motor is in the opposite direction to the hydraulic braking torque output by the brake, outputting positive torque by the first drive motor can reduce the braking torque acting on the front wheels. Furthermore, the second drive motor for driving the rear wheels is controlled to output a first negative torque. Similarly, since the braking torque acting on the front wheels is the sum of the first negative torque output by the first drive motor and the hydraulic braking torque output by the brake, and the first negative torque output by the first drive motor is in the same direction as the hydraulic braking torque output by the brake, outputting first negative torque by the first drive motor can increase the braking torque acting on the rear wheels. This shifts the vehicle's center of gravity rearward, thereby reducing the compression of the suspension due to inertia and the fore-and-aft swaying during braking. Therefore, by dynamically adjusting the torque output of the front wheel motor (first drive motor) and the rear wheel motor (second drive motor), the vehicle's "nodding" and forward and backward swaying can be reduced, improving comfort without affecting the lifespan of the hydraulic valve body or improving the compensation effect.

[0198] It is understood that, in order to achieve the above functions, the electronic device includes hardware and / or software modules that perform the respective functions. Based on the algorithmic steps of the examples described in conjunction with the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is implemented in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application in conjunction with the embodiments, but such implementation should not be considered beyond the scope of this application.

[0199] This embodiment can divide the electronic device into functional modules based on the above method example. For example, each function can be divided into its own functional modules, or two or more functions can be integrated into one processing module. The integrated modules can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and only represents one logical functional division; other division methods may be used in actual implementation.

[0200] This application also provides a computer-readable storage medium storing computer program code. When the processor executes the computer program code, the electronic device executes the relevant method steps in the above method embodiments.

[0201] This application also provides a computer program product that, when run on a computer, causes the computer to execute the relevant method steps described in the above method embodiments.

[0202] The electronic devices, computer storage media, or computer program products provided in this application are all used to execute the corresponding methods provided above. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0203] Through the above description of the embodiments, those skilled in the art can clearly understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0204] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0205] The units described above as separate components may or may not be physically separate. A component shown as a unit can be one or more physical units; that is, it can be located in one place or distributed in multiple different locations. Some or all of the units can be selected based on actual needs to achieve the purpose of this embodiment.

[0206] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The functions of the integrated unit can be implemented in hardware or as software functional units.

[0207] If the integrated units described above are implemented as software functional units and sold or used as independent products, they can be stored in a readable storage medium. Based on this understanding, the technical solutions of the embodiments of this application, in essence, or the contributing parts, or all or part of the technical solutions, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0208] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A control method for a drive motor, characterized in that, The method includes: When the vehicle is braking, if the vehicle speed is greater than or equal to a second threshold and less than or equal to a first threshold, the first drive motor is controlled to output positive torque, and the second drive motor is controlled to output a first negative torque; wherein, the first drive motor is used to drive the front wheels of the vehicle, and the second drive motor is used to drive the rear wheels of the vehicle.

2. The control method for the drive motor according to claim 1, characterized in that, If the vehicle speed is greater than the first threshold, the method further includes: Control the first drive motor to output a second negative torque, and control the second drive motor to output a third negative torque; or; The first drive motor is controlled to output a first preset torque, and the second drive motor is controlled to output a second preset torque.

3. The control method for the drive motor according to claim 2, characterized in that, If the vehicle speed is less than the second threshold, the method further includes: The first drive motor is controlled to output the first preset torque, and the second drive motor is controlled to output the second preset torque.

4. The control method for the drive motor according to claim 2, characterized in that, The method further includes: In the event of slippage of the front wheel and / or the rear wheel, the first compensation torque of the first drive motor is reduced to 0 torque at a target rate, and the second compensation torque of the second drive motor is reduced to 0 torque; the target rate is greater than a third threshold, the first compensation torque is used for the first drive motor to output the positive torque, and the second compensation torque is used for the second drive motor to output the first negative torque.

5. The control method for the drive motor according to any one of claims 2-4, characterized in that, The difference between the first rate at which the first preset torque changes to the positive torque and the second rate at which the second preset torque changes to the first negative torque is less than or equal to a fourth threshold; or the difference between the third rate at which the second negative torque changes to the positive torque and the fourth rate at which the third negative torque changes to the first negative torque is less than or equal to a fourth threshold.

6. The control method for the drive motor according to claim 3, characterized in that, When the vehicle speed is less than a first threshold, the positive torque is less than or equal to the braking torque of the front wheel brakes.

7. The control method for the drive motor according to any one of claims 1-6, characterized in that, The first threshold is 10 km / h, and the second threshold is 1 km / h.

8. A motor controller, characterized in that, include: A memory and one or more processors, the memory storing instructions executable by the one or more processors, the memory storing computer program code including computer instructions that, when executed by the processor, cause the processor to perform the control method for the drive motor as described in any one of claims 1-7.

9. A drive system, characterized in that, The device includes a drive motor and a motor controller as described in claim 8; wherein the motor controller includes a first motor controller and a second motor controller, and the drive motor includes a first drive motor and a second drive motor; the first motor controller is used to control the output torque of the first drive motor, and the second motor controller is used to control the output torque of the second drive motor.

10. A vehicle, characterized in that, It includes wheels, a braking system, a battery, and a drive system as described in claim 9; the battery is connected to the drive system and the braking system, the battery is used to provide electrical energy to the drive system and the braking system, the drive system is used to provide driving torque or braking torque to the wheels, and the braking system is used to provide braking torque to the wheels.

11. A computer-readable storage medium, characterized in that, Includes computer instructions that, when executed on a server, cause the server to perform the control method for the drive motor as described in any one of claims 1-7.

12. A computer program product, characterized in that, When the computer program product is run on a computer, it causes the computer to perform the control method for the drive motor as described in any one of claims 1-7.

Images