Vehicle torque control method, controller and readable storage medium

Abstract

The embodiment of the present application discloses a vehicle torque control method, a controller and a readable storage medium, which relates to the field of vehicle technology and can solve the problems of impact caused by vehicle starting and lifting, acceleration and deceleration switching, and poor overall performance of the vehicle. The method includes obtaining the current driving parameters of the vehicle; determining the current driving condition of the vehicle, the current driving condition includes one of the starting driving condition, the low-speed driving condition and the power drive condition; based on a preset torque distribution scheme, the torque distribution scheme includes at least one of a first distribution scheme and a second distribution scheme; wherein the first distribution scheme includes distributing the target torque to multiple power parts of the vehicle according to a preset torque distribution ratio, and the second distribution scheme includes distributing the target torque to multiple power parts according to the braking timing torque zero, and distributing the target torque. The vehicle torque control method of the present application is used in different driving conditions of the vehicle.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of vehicle technology, and in particular, to a vehicle torque control method, a controller, and a readable storage medium. Background Art

[0002] Against the backdrop of increasingly severe global energy and environmental challenges, environmentally friendly and energy-efficient electric vehicles have become a hot topic. To improve the range of pure electric vehicles, dual-motor four-wheel drive (AWD) electric vehicles with improved economy and power have emerged. For example, electric AWD vehicles with centralized front and rear motors are gaining increasing market share in the mid- to high-end electric vehicle market due to their advantages, such as eliminating some transmission components, improving interior space utilization, and offering flexible drive configurations. The rational distribution of front and rear motor torque is a core technology for AWD vehicles and a direct manifestation of software-defined vehicles. Efficient and rational motor torque distribution can fully leverage the performance of the powertrain and enhance the overall vehicle dynamics.

[0003] Existing torque distribution technologies employ a single principle based on minimizing the combined power consumption of the front and rear motors under various operating conditions. Alternatively, some technologies only adjust torque distribution based on the load ratio between the front and rear axles under specific operating conditions, such as off-road and snowy conditions. However, these technologies present numerous challenges, including vehicle head-up issues during startup, shock from acceleration and deceleration transitions, and poor overall vehicle performance. Summary of the Invention

[0004] The embodiments of the present application provide a vehicle torque control method, a controller, and a readable storage medium, which can solve the problems of impact caused by vehicle starting and lifting, acceleration and deceleration switching, and poor overall performance of the vehicle.

[0005] In a first aspect, an embodiment of the present application provides a vehicle torque control method, the method comprising: obtaining current driving parameters of the vehicle; determining the current driving condition of the vehicle based on the current driving parameters, wherein the current driving condition includes one of a starting driving condition, a low-speed driving condition, and a power drive condition; performing target torque distribution on the current driving condition based on a preset torque distribution scheme, the torque distribution scheme including at least one of a first distribution scheme and a second distribution scheme; wherein the first distribution scheme includes distributing target torque to multiple power parts of the vehicle according to a preset torque distribution ratio, and the second distribution scheme includes distributing target torque to multiple power parts according to a braking timing torque zeroing.

[0006] Specifically, the vehicle's current driving parameters are first acquired. These parameters are not limited and may include, for example, the vehicle's current speed, acceleration, torque, accelerator pedal position, brake pedal position, and so on. These parameters can be acquired through the vehicle's controller as needed. The vehicle's current driving condition is then determined based on the acquired current driving parameters. For example, a low vehicle speed and increasing accelerator pedal position may indicate a starting condition, while a high vehicle speed and slowly increasing brake pedal position may indicate a deceleration condition. Target torque is then distributed based on the current driving condition based on a preset torque distribution scheme, which may include at least one of a first distribution scheme and a second distribution scheme. Among them, the first distribution scheme includes distributing the target torque to the vehicle's multiple power parts according to a preset torque distribution ratio. For example, when there are two power parts, namely the front motor and the rear motor of the vehicle, the vehicle is determined to be in a starting driving condition based on current driving parameters such as the current vehicle speed, the opening of the brake pedal, and the opening of the accelerator pedal. For the current starting driving condition, the front motor and the rear motor are controlled to distribute the target torque according to a preset torque distribution ratio of one to one, or a reasonable torque distribution ratio of two to three, so as to suppress the vehicle's head-up problem caused by excessive torque distribution to one of the front and rear motors.

[0007] Furthermore, to address the impact caused by sudden acceleration or deceleration of the vehicle, the present application also proposes a second torque distribution scheme in an embodiment. This second distribution scheme includes torque zero crossings for multiple power components according to a braking sequence and target torque distribution. Here, braking sequence refers to the torque zero crossings of multiple power components at different times. Specifically, for example, when there are two power components, namely the front and rear motors of the vehicle, the torque zero crossings of the front and rear motors are controlled to occur at different times based on vehicle driving parameters such as the current actual torque, motor speed, motor maximum torque, vehicle speed, driver-requested torque, accelerator pedal opening, and brake pedal opening of the front and rear motors. This prevents simultaneous torque zero crossings when the front and rear motors switch direction, thereby preventing the driver from experiencing a shock caused by the combined effects of the front and rear motors. This torque distribution scheme allows the vehicle to use the appropriate torque distribution scheme under different operating conditions. That is, the first distribution scheme can be used during the vehicle's starting phase, and the second distribution scheme can be used during acceleration and deceleration. This effectively avoids vehicle head-up and impact issues, while also improving the overall performance of the vehicle.

[0008] It should be noted that the multiple power parts can be multiple motors, and the types of the multiple motors can be the same or different. Preferably, there are two power parts, namely the front axle centralized drive motor and the rear axle centralized drive motor of the vehicle, both of which are connected to the wheels through a transmission system, and are respectively referred to as the front motor and the rear motor in this application. In addition, the types of the front motor and the rear motor are not limited. Preferably, the types of the front motor and the rear motor are different, for example, one is a permanent magnet synchronous motor and the other is an AC asynchronous motor. At the same time, the specifications of the front motor and the rear motor are quite different, for example, the extreme torques of the front and rear motors are different. Among them, unless otherwise specified in this application, the multiple power parts are two front motors and rear motors with different specifications.

[0009] In one possible implementation of the present application, the multiple power components include a front motor and a rear motor; the current driving parameters include the vehicle's current speed, the current accelerator pedal opening, the current brake pedal opening, the current actual torque of the front motor and the rear motor, and the driver's current required torque.

[0010] In a possible implementation of the present application, target torque is distributed for the current driving condition based on a preset torque distribution scheme, and the torque distribution scheme includes at least one of a first distribution scheme and a second distribution scheme, including: when the current driving condition is a starting driving condition, the first distribution scheme is adopted to control the front motor and the rear motor to output the first target torque and the second target torque in a positive direction respectively to meet the current required torque; wherein the current required torque is the sum of the first target torque and the second target torque, and the preset torque distribution ratio is a preset ratio of the first target torque to the current required torque, and the preset ratio range is between four tenths and five tenths.

[0011] It should be noted that the value of the first target torque is less than the maximum torque output by the front motor, and the value of the second target torque is less than the maximum torque output by the rear motor. Furthermore, since the maximum torques of the front and rear motors are different, the range of the preset ratio can be adjusted between 4 / 10 and 5 / 10 based on the maximum torques of the front and rear motors. For example, when the maximum torques of the front and rear motors are close, the preset ratio can preferably be set to 5 / 10. When the maximum torques of the front and rear motors differ significantly from each other, the preset ratio can preferably be set to 4 / 10.

[0012] In a possible implementation of the present application, the step of distributing the target torque for the current driving condition based on a preset torque distribution scheme also includes: when the current driving condition is a low-speed driving condition, a second distribution scheme is adopted, and according to the current driving parameters, such as the current required torque, the extreme torques of the front motor and the rear motor, and the current vehicle speed, one of the front motor and the rear motor is used as the main drive motor, and the other is used as the auxiliary drive motor; if the current required torque is less than the extreme torque of the main drive motor, the main drive motor independently outputs the current required torque; if the current required torque is greater than or equal to the maximum output torque of the main drive motor, the main drive motor and the auxiliary drive motor are controlled to pass through zero torque according to the braking sequence, and the target torque is distributed to jointly output the current required torque; wherein the braking sequence includes the auxiliary drive motor reducing its torque to zero before the main drive motor.

[0013] In one possible implementation of the present application, the current driving condition further includes a coasting or braking driving condition, and the target torque is distributed for the current driving condition based on a preset torque distribution scheme, wherein the torque distribution scheme includes at least one of a first distribution scheme and a second distribution scheme. Furthermore, the method further includes: when the current driving condition is a coasting or braking driving condition, adopting the second distribution scheme to, based on the current required torque, the extreme torques of the front and rear motors, and the current vehicle speed, configure one of the front and rear motors as the main drive motor and the other as the main energy recovery motor; and controlling the main drive motor and the main energy recovery motor to have torques passing through zero according to a braking sequence; wherein the braking sequence includes torque direction changes of the main drive motor and the main energy recovery motor at different times. For example, the main energy recovery motor may be controlled to reduce its torque to zero before the main drive motor, or the main energy recovery motor and the main drive motor may not change their torque direction, so that the main drive motor functions solely as the drive motor and does not participate in energy recovery, while only the main energy recovery motor participates in energy recovery, thereby achieving the second control under acceleration and deceleration conditions.

[0014] In one possible implementation of the present application, the braking sequence also includes the main energy recovery motor changing the direction of torque before the main drive motor, or the torque direction of the main drive motor and the main energy recovery motor not changing. With such a design, for example, the main energy recovery motor can be used only as an energy recovery motor and not as a drive function motor. In this way, the main energy recovery motor is always ready for reversing under different working conditions. For example, when the main drive motor needs to be reversed during coasting or braking, the main energy recovery motor is reversed before the main drive motor, thereby avoiding the two motors from reversing at the same time. For another example, the main energy recovery motor can also be used as a motor with a drive function. When the vehicle is driving normally at a fixed speed, the main drive motor and the main energy recovery motor output torque in the forward direction at the same time. However, when the main drive motor and the main energy recovery motor both need to be reversed during sudden deceleration, the main energy recovery motor can be reversed before the main drive motor to avoid the impact superposition problem caused by the simultaneous reversing of the two motors.

[0015] In one possible implementation of the present application, the torque distribution scheme further includes a third distribution scheme, and the steps of distributing the target torque to the current driving condition based on the preset torque distribution scheme include: when the current condition is a power-driven condition, using the third distribution scheme to obtain the initial distribution torque of multiple power components based on the current driving parameters; and distributing the target torque to the multiple power components based on the third distribution scheme; wherein the third distribution scheme distributes the target torque based on the load ratio of the front and rear axles of the vehicle. Here, the vehicle's driving parameters may also include the load parameters of the front and rear axles of the vehicle, the acceleration of the vehicle, and the road slope. The strong power distribution scheme includes adjusting the distribution ratio based on the load ratio of the front and rear axles, the acceleration of the vehicle, and the road slope.

[0016] In a possible implementation of the present application, the torque distribution scheme also includes a fourth distribution scheme, and the current driving condition also includes an economical drive driving condition corresponding to the economic distribution scheme. The step of performing target torque distribution on the current driving condition based on the preset torque distribution scheme includes: when the current driving condition is an economical drive driving condition, adopting the fourth distribution scheme; obtaining the initial distribution torque of the vehicle based on the current driving parameters; and obtaining the target torque distribution of multiple power components based on the preset fourth distribution scheme, wherein the fourth distribution scheme adopts a torque distribution strategy with the least power consumption for multiple power components.

[0017] Secondly, the present application provides a vehicle controller comprising a vehicle control unit and a motor control unit. The vehicle control unit is used to obtain the vehicle's current driving parameters, such as the vehicle's speed, acceleration, current torque, accelerator pedal opening, brake pedal opening, and front and rear axle load information, and based on the current driving parameters, obtain the vehicle's current required torque and determine the current driving condition. The motor control unit can distribute target torque to the current driving condition according to a preset torque distribution scheme and achieve torque response of the power components. This vehicle controller can solve the vehicle's head-up problem during startup, the impact caused by switching between acceleration and deceleration, and the problem of poor overall vehicle performance.

[0018] In a third aspect, the present application further provides a readable storage medium storing machine-executable instructions. When the machine-executable instructions are called and executed by a processor, the machine-executable instructions can cause the processor to execute any of the vehicle torque control methods described in the first aspect. Because the readable storage medium can execute any of the vehicle torque control methods described in the first aspect, it has the same beneficial effects as the first aspect, namely, the readable storage medium can address the impact caused by vehicle head-up, acceleration, and deceleration switching during the vehicle's starting phase, as well as the poor overall vehicle performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of a vehicle control method provided in an embodiment of the present application Figure 1 ;

[0020] Figure 2 A schematic diagram of a process flow for a vehicle starting and driving condition in a vehicle control method provided in an embodiment of the present application;

[0021] Figure 3 A schematic diagram of a process flow of a vehicle under low-speed driving conditions in a vehicle control method provided in an embodiment of the present application;

[0022] Figure 4 A schematic diagram of a process flow in a vehicle control method under coasting or braking conditions provided in an embodiment of the present application;

[0023] Figure 5 A schematic diagram of a flow chart under a power driving condition in a vehicle control method provided in an embodiment of the present application;

[0024] Figure 6 A schematic diagram of a flow chart under an economical driving condition in a vehicle control method provided in an embodiment of the present application;

[0025] Figure 7 A schematic diagram of a vehicle control system provided in an embodiment of the present application;

[0026] Figure 8 A schematic diagram of a control logic flow in a vehicle control method provided in an embodiment of the present application;

[0027] Figure 9 A schematic diagram of a vehicle controller provided in an embodiment of the present application.

[0028] Reference numerals:

[0029] 1-Front motor; 2-Rear motor; 3-Front gearbox; 4-Rear gearbox; 5-Vehicle control unit; 6-Front motor control unit; 7-Rear motor control unit; 8-Power battery; 9-Wheel. DETAILED DESCRIPTION

[0030] To make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the specific technical solutions of the present application will be further described in detail below in conjunction with the drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application but are not intended to limit the scope of the present application.

[0031] In the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of this application, unless otherwise specified, "multiple" means two or more.

[0032] In addition, in the embodiments of the present application, directional terms such as "up", "down", "left" and "right" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they may change accordingly according to changes in the orientation of the components in the drawings.

[0033] In the embodiments of the present application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integrated connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0034] In the embodiments of the present application, the terms "comprises," "comprising," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0035] In the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of this application should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0036] With the rapid development of pure electric vehicles, many models are adopting four-wheel drive solutions, employing a front and rear electric drive system to achieve superior performance. These systems control the torque output of the front and rear motors according to a specific ratio. The torque distribution is adjusted in real time based on vehicle driving conditions, such as curves, slopes, highways, snow, mud, and sand, as well as user operations such as acceleration, braking, steering, forward movement, and reverse movement.

[0037] However, for general four-wheel drive torque distribution schemes, the following problems are still inevitable in actual applications: First, the large torque and fast response of the motor cause the vehicle to lift its head when starting; second, there is a gap at the meshing point between the motor output shaft and the reducer gear in the electric drive transmission mechanism, which causes an impact when the output torque switches in the positive and reverse directions, that is, when the front and rear motor torques pass through zero. Especially under low vehicle speed conditions, users will feel this impact more obviously; third, a single four-wheel drive torque distribution scheme is usually used to adapt to a variety of different working conditions, resulting in poor overall performance of the vehicle.

[0038] In the present application, refer to Figure 7 , provides a pure electric vehicle system driven by centralized front and rear power motors. This four-wheel drive electric system includes a front axle centralized drive motor, namely front motor 1, a rear axle centralized drive motor, namely rear motor 2, a power battery 8, a front gearbox 3 and a rear gearbox 4, a vehicle control unit 5, and motor control units including a front motor control unit 6 and a rear motor control unit 7. Both the front motor 1 and the rear motor 2 are connected to wheels 9 via a transmission system; the power battery 8 is used to provide and recover electrical energy to the front motor 1 and the rear motor 2. The power battery 8 includes one or more of a lithium-ion power battery 8, a flywheel energy storage battery system, and a fuel cell system.

[0039] In addition, refer to Figure 7 and Figure 9, an embodiment of the present application provides a vehicle controller, which includes a vehicle control unit 5 and a motor control unit. The vehicle control unit 5 is used to obtain the current driving parameters of the vehicle, and as the main controller of the vehicle, coordinate various systems to complete the distribution calculation of the required torque of the front motor 1 and the rear motor 2, and obtain the current required torque of the vehicle and determine the current driving condition based on the current driving parameters. The motor control unit includes a front motor control unit 6 and a rear motor control unit 7, which are used to distribute the target torque to the current driving condition according to a preset torque distribution scheme and realize the torque response of the power component.

[0040] The present application also provides a vehicle torque control method, referring to Figure 1 , the method comprising:

[0041] Step S100: obtaining the current driving parameters of the vehicle;

[0042] Step S200: determining a current driving condition of the vehicle based on current driving parameters, where the current driving condition includes one of a starting driving condition, a low-speed driving condition, and a power driving condition;

[0043] Step S300: distributing a target torque for the current driving condition based on a preset torque distribution scheme, where the torque distribution scheme includes at least one of a first distribution scheme and a second distribution scheme;

[0044] Among them, the first distribution scheme includes distributing the target torque to multiple power parts of the vehicle according to a preset torque distribution ratio, and the second distribution scheme includes distributing the target torque to multiple power parts according to the torque zero crossing of the braking time sequence.

[0045] Specifically, in step S100, the current driving parameters may be the current vehicle speed, acceleration, torque, accelerator pedal opening, brake pedal opening, etc., which may be obtained through the vehicle controller according to actual needs, and there is no limitation on the specific type of the current driving parameters.

[0046] In step S200, the vehicle's current driving condition is determined based on the acquired current driving parameters. For example, a low vehicle speed and a widening accelerator pedal opening can be considered a starting condition. Alternatively, a low vehicle speed and frequent switching between the brake and accelerator pedal openings within a predetermined time period can be considered a low-speed driving condition. Subsequently, in step S300, a target torque distribution is determined for the current driving condition based on a predetermined torque distribution scheme, which includes at least one of a first distribution scheme and a second distribution scheme. Among them, the first distribution scheme includes distributing the target torque to multiple power parts of the vehicle according to a preset torque distribution ratio. For example, when there are two power parts, namely the front motor 1 and the rear motor 2 of the vehicle, the vehicle is determined to be in a starting driving condition based on current driving parameters such as the current vehicle speed, the opening of the brake pedal, and the opening of the accelerator pedal. For the current starting driving condition, the front motor 1 and the rear motor 2 are controlled to distribute the target torque according to a preset torque distribution ratio of five to five, or four to six or other reasonable torque distribution ratios to suppress the vehicle's head-up problem caused by excessive torque distribution of one of the front and rear motors 2.

[0047] Furthermore, to address the impact caused by sudden acceleration or deceleration switching of the vehicle under low-speed driving conditions, in step S300, the embodiment of the present application also proposes a second distribution scheme, wherein the second distribution scheme includes controlling the torque zero crossing of multiple power components according to the braking time sequence and performing target torque distribution. The braking time sequence torque zero crossing refers to the torque zero crossing of multiple power components at different times, or controlling the torque zero crossing of multiple power components at a preset time interval. Specifically, for example, when there are two power components, namely the front motor 1 and the rear motor 2 of the vehicle, the torque zero crossing of the front motor 1 and the rear motor 2 is controlled to occur at different times based on the current actual torque, motor speed, motor maximum torque, vehicle speed, driver demand torque, accelerator pedal opening, brake pedal opening, and other vehicle driving parameters of the front motor 1 and the rear motor 2. This avoids the torque zero crossing occurring simultaneously when the front and rear motors 2 switch, thereby preventing the impact felt by the driver from being the result of the superposition of the front motor 1 and the rear motor 2. The above torque distribution method enables the vehicle to use the corresponding torque distribution scheme under different working conditions. That is, the first distribution scheme can be used during the vehicle's starting phase, and the second scheme can be used during the acceleration and deceleration phase. This effectively avoids the vehicle's head-up and impact problems, while improving the overall performance of the vehicle.

[0048] It should be noted that the multiple power parts can be multiple motors, and the types of the multiple motors can be the same or different. Preferably, there are two power parts, namely the front axle centralized drive motor and the rear axle centralized drive motor of the vehicle, and both are connected to the wheels 9 through a transmission system, respectively referred to as the front motor 1 and the rear motor 2. In addition, the types of the front motor 1 and the rear motor 2 are not limited. Preferably, the front motor 1 and the rear motor 2 are of different types, for example, one is a permanent magnet synchronous motor and the other is an AC asynchronous motor. At the same time, the specifications of the front motor 1 and the rear motor 2 are quite different, for example, the extreme torques of the front and rear motors 2 are different. Among them, unless otherwise specified in this application, the multiple power parts are the front motor 1 and the rear motor 2 with two different specifications.

[0049] In some embodiments, reference Figure 1 and Figure 7 In step S100, the current driving parameters acquired include the vehicle's current speed, the current accelerator pedal opening, the current brake pedal opening, the current actual torques of the front and rear motors, and the driver's current torque demand. It should be noted that the current vehicle driving parameters are not limited to the vehicle's current speed, the current accelerator pedal opening, the current brake pedal opening, the current actual torques of the front and rear motors, and the driver's current torque demand. They may also include the vehicle's current acceleration, the current road gradient, and the like, without specific limitation. The acquired current vehicle driving parameters are based on the vehicle control unit 5 and the motor control unit's ability to determine the current driving condition and achieve the target torque and respond accordingly.

[0050] Reference Figure 1 、 Figure 2 and Figure 7 Step S300 includes step S301. Step S301: when the current driving condition is a starting driving condition, a first distribution scheme is adopted to control the front motor 1 and the rear motor 2 to output the first target torque and the second target torque in a positive direction respectively to meet the current required torque; wherein the current required torque is the sum of the first target torque and the second target torque, and the preset torque distribution ratio is a preset ratio of the first target torque to the current required torque, and the preset ratio range is between four tenths and five tenths.

[0051] It should be noted that the value of the first target torque is less than the extreme torque output by the front motor 1, and the value of the second target torque is less than the extreme torque output by the rear motor 2. In addition, since the extreme torques of the front motor 1 and the rear motor 2 are different, the range of the preset ratio can be adjusted between 4 / 10 and 5 / 10 according to the extreme torques of the front motor 1 and the rear motor 2. For example, when the extreme torques of the front motor 1 and the rear motor 2 are close, the preset ratio can preferably be set to 5 / 10; when the extreme torque of the front motor 1 is greater than the extreme torque of the rear motor 2, the preset ratio can preferably be set to 4 / 10.

[0052] Reference Figure 1 、 Figure 3 and Figure 7 Step S300 further includes step S302, wherein: when the current driving condition is a low-speed driving condition, a second allocation scheme is adopted, wherein one of the front motor 1 and the rear motor 2 is used as the main drive motor and the other is used as the auxiliary drive motor according to the current driving parameters; step S302 further includes step S3021, wherein step S3021 determines whether the current required torque is less than the extreme torque of the main drive motor. If the current required torque is less than the extreme torque of the main drive motor, step S3021a is performed: the main drive motor independently outputs the current required torque; if the current required torque is greater than or equal to the maximum output torque of the main drive motor, step S3021b is performed: the main drive motor and the auxiliary drive motor are controlled to pass through zero torque according to a braking sequence, and target torque allocation is performed to jointly output the current required torque; wherein the braking sequence includes the auxiliary drive motor reducing its torque to zero torque before the main drive motor.

[0053] Reference Figure 3 、 Figure 4 and Figure 7, the current driving condition also includes a coasting or braking driving condition, step S300 also includes step S303, step S303: when the current driving condition is a coasting or braking driving condition, the second allocation scheme is adopted, and one of the front motor 1 and the rear motor 2 is used as the main drive motor and the other is used as the main energy recovery motor according to the current driving parameters; for example, the current driving parameters include the current required torque, the extreme torques of the front motor 1 and the rear motor 2, the current vehicle speed, etc., and one main drive motor and the other can be determined as the main energy recovery motor based on them, and step S303 includes step S3031: controlling the main drive motor and the main energy recovery motor to pass through zero torque according to the braking sequence; wherein the braking sequence includes the torque direction changes of the main drive motor and the main energy recovery motor at different times. For example, the main energy recovery motor can be controlled to reduce its torque to zero before the main drive motor, or the main energy recovery motor and the main drive motor do not change their torque direction, so that the main drive motor is used alone as a drive motor and does not participate in energy recovery, and only the main energy recovery motor participates in energy recovery, thereby realizing the second distribution scheme under acceleration and deceleration conditions.

[0054] In some embodiments, the braking sequence also includes the main energy recovery motor changing the direction of torque before the main drive motor, or the torque direction of the main drive motor and the main energy recovery motor not changing. With such a design, for example, the main energy recovery motor can be used only as an energy recovery motor and not as a drive function motor. In this way, the main energy recovery motor is always ready for reversing under different working conditions. When the main drive motor needs to reverse during coasting or braking, the main energy recovery motor reverses before the main drive motor, thereby avoiding the two motors reversing at the same time. For another example, the main energy recovery motor can also be used as a motor with a drive function. When the vehicle is driving normally near a fixed speed, the main drive motor and the main energy recovery motor simultaneously output torque in a positive direction. When the main drive motor and the main energy recovery motor both need to reverse during sudden deceleration, the main energy recovery motor can be reversed before the main drive motor to avoid the impact superposition problem caused by the simultaneous reversing of the two motors.

[0055] In some embodiments, reference Figure 1 and Figure 5The torque distribution scheme also includes a third distribution scheme. The current driving condition also includes step S200 and then step S400. Step S400: When the current driving condition is a strong power drive condition, the third distribution scheme is adopted to obtain an initial distributed torque for multiple power components based on the current driving parameters; target torque distribution is performed on the multiple power components based on the third distribution scheme; wherein the third distribution scheme distributes the target torque based on the load ratio between the front and rear axles of the vehicle. Here, the vehicle driving parameters include the load parameters of the front and rear axles of the vehicle, the vehicle acceleration, and the road slope. The third distribution scheme, also known as the strong power distribution scheme, includes adjusting the distribution ratio based on the load ratio between the front and rear axles, the vehicle acceleration, and the road slope. Specifically, for example, the strong power distribution scheme is preferred in situations where the driver is insensitive to impact, in strong acceleration conditions, and in driving modes with high power requirements (such as off-road mode or snow mode) to ensure the driver's power needs. The power drive distribution scheme primarily considers the load ratio between the front and rear axles and can adjust the distribution ratio based on the vehicle acceleration and road slope.

[0056] In some embodiments, reference Figure 1 and Figure 6 The torque distribution scheme also includes a fourth distribution scheme, and the current driving condition also includes an economical driving condition corresponding to the fourth distribution scheme. Figure 6 Step S200 is followed by step S500. Step S500: When the current driving condition is an economical driving condition, a fourth distribution scheme is adopted; an initial distributed torque of the vehicle is obtained based on the current driving parameters; and a target torque distribution for the multiple power components is obtained based on the preset fourth distribution scheme, wherein the fourth distribution scheme adopts a torque distribution strategy that minimizes the power consumption of the multiple power components. Specifically, the target torque distribution for the front motor 1 and the rear motor 2 is obtained based on the preset fourth distribution scheme. The fourth distribution scheme primarily considers the electric power consumed by the front motor 1 and the rear motor 2, thereby adopting a target torque distribution strategy that minimizes the electric power consumption of the front motor 1 and the rear motor 2. In this way, the appropriate distribution scheme can be selected for different driving conditions to improve the overall performance of the vehicle.

[0057] Reference Figure 7 and Figure 8 ,in, Figure 8This is a schematic diagram of the control logic for the torque distribution scheme in the embodiment of this application. Specifically, a first distribution scheme is employed during the vehicle's launch phase to suppress the vehicle's head-up tilt caused by high starting torque, also known as an anti-head-up distribution scheme. For example, a fuzzy control method can be used to identify the vehicle's starting conditions by combining vehicle speed, brake pedal position, and accelerator pedal position. Then, based on these conditions, the first distribution scheme is employed, where the ratio of front motor 1 to total drive is controlled to between 40% and 50%. This reduces the vehicle's head-up tilt by driving both the front and rear motors 2. To address the impact of acceleration and deceleration switching, which often occurs during low-speed driving, a second allocation scheme, or an impact-resistant four-wheel drive torque allocation scheme, is proposed in this application example. This scheme first obtains basic information such as the actual motor torque, motor speed, motor peak torque, vehicle speed, driver-required torque, accelerator pedal, and vehicle mode for calculation of the second allocation scheme. Secondly, based on the driver's required torque, motor peak torque, and vehicle speed, one of the front motor 1 and rear motor 2 is determined to be the main drive motor and the other to be the auxiliary drive motor, or one of the front motor 1 and rear motor 2 is determined to be the main energy recovery motor and the other to be the main drive motor. The main drive torque and energy recovery torque are required to be different motors. When determining the coasting recovery motor, the maximum recovery limit capacity must be considered, and the coasting recovery motor must be within the maximum recovery capacity range. During driving, the main drive motor is used as the primary motor, and the auxiliary drive motor is used only when the required torque exceeds the capacity of the main drive motor. The energy recovery motor is used for coasting and braking energy recovery. Finally, by rationally using the main drive motor and the main energy recovery motor according to the working conditions, the torque direction of the two motors can be controlled to not change at the same time. For example, the auxiliary drive motor can be controlled to reduce its torque to zero before the main drive motor. Alternatively, the torque direction of the two motors can be kept constant. For example, only the main drive motor can be used for driving, and only the energy recovery motor can be used for energy recovery, so as to achieve impact prevention control.

[0058] Continue, refer to Figure 7 and Figure 8 The third distribution scheme, also known as the power drive distribution scheme, is preferred in situations where the driver is insensitive to impact, during strong acceleration, or in driving modes requiring high power (such as off-road mode or snow mode) to ensure the driver's power needs. The power drive distribution scheme primarily considers the axle load ratio between the front and rear axles and can be adjusted based on vehicle acceleration and road gradient.

[0059] Under most operating conditions, such as high-speed driving on highways, the economical distribution ratio of the front and rear motors 2 is selected to improve the vehicle's endurance. The fourth distribution scheme can be adopted, which can also be called the economical drive distribution scheme. In this scheme, the electric power consumed by the front motor 1 and the rear motor 2 can be mainly considered, and the basic principle of distribution is to minimize the sum of the electric power consumed by the front motor 1 and the rear motor 2.

[0060] In addition, an embodiment of the present application also provides a readable storage medium, which stores machine-executable instructions. When the machine-executable instructions are called and executed by a processor, the machine-executable instructions can enable the processor to execute the vehicle torque control method in the embodiment of the present application.

[0061] The above method can realize the use of corresponding distribution methods according to different driving needs, achieve a balance between power, economy and drivability, and improve the comprehensive performance of the vehicle; and in order to solve the problem of vehicle head-up during starting, an anti-head-up four-wheel drive torque distribution scheme is proposed to reduce the vehicle's head-up feeling; for the impact problem of switching between acceleration and deceleration conditions, an anti-impact distribution scheme is proposed. Through the rational use of the front and rear motors, the tooth surface meshing impact caused by the motor torque passing through zero is avoided to solve the vehicle impact problem; through the four-wheel drive torque distribution scheme of power drive distribution and economic drive distribution, the vehicle's power, economy and overall comprehensive performance are balanced.

[0062] The serial numbers of the embodiments of this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. The above are only preferred embodiments of this application and do not limit the scope of the patent of this application. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the scope of patent protection of this application.

Claims

1. A vehicle torque control method, characterized in that: include: Get the current driving parameters of the vehicle; determining a current driving condition of the vehicle according to the current driving parameter, wherein the current driving condition includes one of a starting driving condition, a low-speed driving condition, and a power driving condition; performing target torque distribution for the current driving condition based on a preset torque distribution scheme, wherein the torque distribution scheme includes at least one of a first distribution scheme and a second distribution scheme; The first distribution scheme includes distributing the target torque to the plurality of power components of the vehicle according to a preset torque distribution ratio, and the second distribution scheme includes distributing the target torque to the plurality of power components according to a braking time sequence torque zero crossing. The plurality of power components include a front motor and a rear motor, the current driving condition further includes a coasting or braking driving condition, and the step of distributing the target torque to the current driving condition based on a preset torque distribution scheme, wherein the torque distribution scheme includes at least one of a first distribution scheme and a second distribution scheme, further includes: When the current driving condition is the coasting or braking driving condition, the second allocation scheme is adopted to use one of the front motor and the rear motor as the main drive motor and the other as the main energy recovery motor according to the current driving parameters; The main drive motor and the main energy recovery motor are controlled to pass through zero torque according to the braking sequence; wherein the braking sequence includes the main drive motor and the main energy recovery motor having torque direction changes at different times.

2. The vehicle torque control method according to claim 1, characterized in that: The current driving parameters include the current speed of the vehicle, the current accelerator pedal opening, the current brake pedal opening, the current actual torques of the front motor and the rear motor, and the current required torque of the driver.

3. The vehicle torque control method according to claim 2, characterized in that: The step of distributing the target torque to the current driving condition based on the preset torque distribution scheme includes: When the current driving condition is the starting driving condition, the first distribution scheme is adopted to control the front motor and the rear motor to respectively output a first target torque and a second target torque in a positive direction to meet the current required torque; The currently required torque is the sum of the first target torque and the second target torque, and the preset torque distribution ratio is a preset ratio of the first target torque to the currently required torque, and the preset ratio ranges from 4 / 10 to 5 / 10.

4. The vehicle torque control method according to claim 2, characterized in that: The step of distributing the target torque to the current driving condition based on a preset torque distribution scheme, wherein the torque distribution scheme includes at least one of a first distribution scheme and a second distribution scheme, further includes: When the current driving condition is the low-speed driving condition, the second allocation scheme is adopted, and according to the current driving parameters, one of the front motor and the rear motor is used as the main drive motor, and the other is used as the auxiliary drive motor; If the current required torque is less than the extreme torque of the main drive motor, the main drive motor independently outputs the current required torque; If the currently required torque is greater than or equal to the maximum output torque of the main drive motor, the main drive motor and the auxiliary drive motor are controlled to pass through zero torque according to the braking sequence, and the target torque is distributed to jointly output the currently required torque; wherein, the braking sequence includes the auxiliary drive motor reducing its torque to zero torque before the main drive motor.

5. The vehicle torque control method according to claim 4, characterized in that: The braking sequence also includes the main energy recovery motor changing its torque direction before the main drive motor, or the main drive motor and the main energy recovery motor not changing their torque directions.

6. The vehicle torque control method according to claim 1, characterized in that: The torque distribution scheme further includes a third distribution scheme. The step of distributing the target torque to the current driving condition based on the preset torque distribution scheme includes: When the current driving condition is the power drive condition, the third distribution scheme is adopted to obtain the initial distribution torque of the plurality of power components according to the current driving parameters; and the target torque is distributed to the plurality of power components based on the third distribution scheme; The third distribution scheme distributes the target torque according to the load ratio between the front axle and the rear axle of the vehicle.

7. The vehicle torque control method according to claim 1, characterized in that: The torque distribution scheme further includes a fourth distribution scheme, and the current driving condition further includes an economical driving driving condition corresponding to the fourth distribution scheme. The step of distributing the target torque to the current driving condition based on the preset torque distribution scheme includes: When the current driving condition is an economical driving condition, the fourth distribution scheme is adopted; and the initial distribution torque of the vehicle is obtained according to the current driving parameters; The target torque distribution of the plurality of power components is obtained based on the preset fourth distribution scheme, wherein the fourth distribution scheme adopts a torque distribution strategy that minimizes power consumption of the plurality of power components.

8. A vehicle controller configured to execute the vehicle torque control method according to any one of claims 1 to 7, characterized in that: include: A vehicle control unit, configured to obtain current driving parameters of the vehicle, and based on the current driving parameters, obtain the current required torque of the vehicle and determine the current driving condition; The motor control unit is used to distribute the target torque to the current driving condition according to a preset torque distribution scheme and realize the torque response of the power component.

9. A readable storage medium, characterized in that The readable storage medium stores machine executable instructions. When the machine executable instructions are called and executed by the processor, the machine executable instructions can enable the processor to execute the vehicle torque control method according to any one of claims 1 to 7.

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