Vehicle control method and system, equipment, medium and product

Abstract

The invention relates to a vehicle control method and system, equipment, a medium and a product. The control method comprises the steps that operation parameters of the vehicle are obtained; wherein the operation parameters comprise the load of each wheel of the vehicle; determining a target yawing moment of the vehicle according to the running parameters of the vehicle; based on the target yawing moment and the load of each wheel, target braking force and target driving force of each wheel are determined; and driving the vehicle to run according to the target braking force and the target driving force. The target braking force and the target driving force are distributed to each wheel, the regenerative braking torque of the motor is combined with the yawing torque requirement of the vehicle, the regenerative braking torque is preferentially used, the energy recovery efficiency of the vehicle is improved, and the stability and the energy efficiency of the vehicle are improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a vehicle control method and system, equipment, medium, and product. Background Art

[0002] With the popularity of electric vehicles, vehicle dynamic stability and energy recovery systems have gradually become the focus of technological development. However, in existing electric vehicle control systems, the energy recovery function is usually independent of the vehicle dynamic stability control. When the vehicle slips or becomes unstable, the system prioritizes yaw stability, resulting in low energy recovery efficiency. Therefore, a vehicle control method is urgently needed to maximize energy recovery efficiency while improving vehicle dynamic stability. Summary of the invention

[0003] Based on this, a vehicle control method and system, equipment, medium, and product are provided to improve / solve the problem of low energy recovery efficiency of vehicles in the prior art.

[0004] In a first aspect, a vehicle control method is provided, the control method comprising:

[0005] Acquiring operating parameters of the vehicle; wherein the operating parameters include the load of each wheel of the vehicle;

[0006] determining a target yaw moment of the vehicle according to an operating parameter of the vehicle;

[0007] Based on the target yaw moment and the load of each wheel, respectively determine a target braking force and a target driving force of each wheel;

[0008] The vehicle is driven to travel according to the target braking force and the target driving force.

[0009] Optionally, the operating parameters include the current position of the vehicle, the front wheel angle, the actual yaw rate, and the longitudinal speed;

[0010] Then, determining the target yaw moment of the vehicle according to the operating parameters of the vehicle includes:

[0011] determining a target yaw rate of the vehicle based on a preset first correspondence among the longitudinal speed, the actual yaw rate, the wheelbase of the vehicle, the front wheel turning angle, and a curve curvature radius, the curve curvature radius indicating a road curvature radius of the vehicle at the current position;

[0012] A target yaw moment of the vehicle is determined based on a preset second corresponding relationship among the rotational inertia of the vehicle around a preset coordinate system, the target yaw rate, and the actual yaw rate.

[0013] Optionally, the determining the target braking force and the target driving force of each wheel based on the target yaw moment and the load of each wheel respectively includes:

[0014] determining the energy recovery power of each wheel based on the load of each wheel; the energy recovery power indicates the power of converting the kinetic energy of the wheel into electrical energy and storing it in the battery;

[0015] determining an initial braking force of each wheel based on the energy recovery power of each wheel;

[0016] determining a target driving force for each wheel based on the target yaw moment;

[0017] The target braking force is determined based on the initial braking force and the energy recovery efficiency of the vehicle; the energy recovery efficiency indicates the proportion of energy converted into electrical energy from the kinetic energy of the vehicle and stored in a battery, the energy recovery efficiency is determined based on the regenerative braking torque of each wheel, and the regenerative braking torque is determined based on the operating data of the motor corresponding to each wheel.

[0018] Optionally, determining the energy recovery power of each wheel based on the load of each wheel includes:

[0019] In response to the vertical load of the first wheel being greater than the vertical load of the second wheel, determining to distribute the total energy recovery power of the vehicle to the first wheel until the energy recovery power of the first wheel reaches a first recovery power threshold; wherein the total energy recovery power indicates the total power of converting kinetic energy of the vehicle into electrical energy and storing it in a battery, the total energy recovery power is determined according to the regenerative braking torque of each wheel, and the first recovery power threshold is determined according to a charging threshold of the vehicle;

[0020] The allocated total energy recovery power is allocated to the second wheel until the energy recovery power of the second wheel reaches a second recovery power threshold; wherein the second recovery power threshold is determined according to a charging threshold of the vehicle.

[0021] Optionally, determining the target braking force according to the initial braking force and the energy recovery efficiency of the vehicle includes:

[0022] The target braking force is determined according to a preset third corresponding relationship among the initial braking force, the energy recovery efficiency, the driving torque of each wheel and the vertical load of each wheel; wherein the vertical load of each wheel is determined according to the longitudinal force of each wheel, and the longitudinal force of each wheel is determined according to the target yaw moment.

[0023] Optionally, driving the vehicle to travel according to the target braking force and the target driving force includes:

[0024] In response to the target braking force being less than the braking force corresponding to the target yaw moment, obtaining a compensatory braking force generated by the hydraulic braking force of the vehicle; wherein the sum of the target braking force and the supplementary braking force is the braking force corresponding to the target yaw moment;

[0025] The vehicle is driven to travel according to the target braking force, the supplementary braking force, and the target driving force.

[0026] In a second aspect, a control system of a vehicle is provided, the control system comprising:

[0027] An acquisition module, used for acquiring operating parameters of the vehicle; wherein the operating parameters include the load of each wheel of the vehicle;

[0028] A first determination module, configured to determine a target yaw moment of the vehicle according to an operating parameter of the vehicle;

[0029] a second determination module, configured to determine a target braking force and a target driving force of each wheel based on the target yaw moment and the load of each wheel;

[0030] A driving module is used to drive the vehicle to travel according to the target braking force and the target driving force.

[0031] According to a third aspect, an electronic device is provided, comprising a memory, a processor, and a computer program stored in the memory and used to run on the processor, wherein the processor implements the control method according to the first aspect when executing the computer program.

[0032] According to a fourth aspect, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the control method according to the first aspect is implemented.

[0033] According to a fifth aspect, a computer program product is provided, comprising a computer program, wherein when the computer program is executed by a processor, the control method according to the first aspect is implemented.

[0034] On the basis of conforming to the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present application.

[0035] The control method, system, device, medium, and product of the above-mentioned vehicle determine the target yaw moment of the vehicle based on the operating parameters of the vehicle, and allocate target braking force and target driving force to each wheel respectively through the target yaw moment and the load of each vehicle to drive the vehicle. By allocating target braking force and target driving force to each wheel respectively, the motor regenerative braking torque is combined with the yaw moment requirement of the vehicle, and the regenerative braking torque is used preferentially, so as to increase the energy recovery efficiency of the vehicle and achieve a dual improvement in vehicle stability and energy efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a first flow chart of a vehicle control method in one embodiment;

[0037] Figure 2 is a second flow chart of a vehicle control method in one embodiment;

[0038] Figure 3 is a schematic structural diagram of a control system of a vehicle in one embodiment;

[0039] Figure 4 FIG. 1 is a schematic diagram of the structure of an electronic device in an embodiment. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0041] It should be noted that the diagram provided in the present embodiment only illustrates the basic concept of the present application in a schematic manner, so the diagram only shows the components related to the present application rather than drawing according to the number, shape and size of the components during actual implementation. The type, quantity and ratio of each component during actual implementation can be a random change, and its component layout type may also be more complicated. The structure, ratio, size, etc. illustrated by the accompanying diagram of this specification are only used to match the content disclosed in the specification, so that people familiar with this technology can understand and read, and are not used to limit the restrictive conditions that can be implemented in this application, so they have no technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effect that can be produced by this application and the purpose that can be achieved, should still fall within the scope that the technical content disclosed in this application can cover. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are also only for the convenience of narration, rather than for limiting the scope that can be implemented in this application. The change or adjustment of its relative relationship, without substantial change of technical content, should also be regarded as the scope that can be implemented in this application.

[0042] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the text does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0043] As shown in this document, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural, unless the context clearly indicates an exception. Generally speaking, the terms "include" and "comprise" only indicate that the steps and elements that have been clearly identified are included, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0044] The definitions of inclusion in this document, such as the terms "having", "may have", "include" or "may include" used herein, indicate the existence of the corresponding functions, operations, elements, etc. herein, and do not limit the existence of one or more other functions, operations, elements, etc. In addition, it should be understood that the terms "including" or "having" used herein indicate the existence of the features, numbers, steps, operations, elements, components, or a combination thereof described in the specification, without excluding the existence or addition of one or more other features, numbers, steps, operations, elements, components, or a combination thereof.

[0045] In the embodiments of the present application, prefixes such as "first" and "second" are used only to distinguish different description objects, and have no limiting effect on the position, order, priority, quantity or content of the described objects. The use of prefixes such as ordinal numbers to distinguish description objects in the embodiments of the present application does not constitute a limitation on the described objects. For the statement of the described objects, please refer to the description in the context of the claims or embodiments, and no unnecessary limitation should be constituted due to the use of such prefixes. In addition, in the description of the present embodiment, unless otherwise specified, the meaning of "multiple" is two or more.

[0046] With the popularity of electric vehicles, vehicle dynamic stability control and energy recovery systems have gradually become the focus of technological development. However, the relevant technologies have the following defects: 1. Energy recovery is disconnected from dynamic stability control: In existing electric vehicle control systems, the energy recovery function is usually independent of vehicle dynamic stability control. When the vehicle skids or loses stability, the system prioritizes yaw stability and often compensates through hydraulic brakes, but ignores the use of motor regenerative braking torque, resulting in low energy recovery efficiency. Especially on low-adhesion surfaces, such as slippery or icy roads, the lack of a coordinated strategy between energy recovery and stability control can easily lead to corresponding lag or reduced handling performance of the vehicle. 2. Limited use of regenerative braking torque: Electric vehicles have limited ability to provide regenerative braking torque at high battery capacity, low power or high / low motor speed. Existing systems rely too much on hydraulic brakes in these scenarios and do not fully tap the braking potential of the motor. In addition, the motor's energy recovery capacity is affected by the battery charging power limit and cannot meet the vehicle's braking force requirements in a short period of time, resulting in unsatisfactory vehicle dynamic control. 3. Lack of comprehensive optimization of torque distribution strategy: The current torque distribution system mainly targets the vehicle's yaw stability requirements, often ignoring the optimization of energy recovery efficiency, and the torque distribution does not take into account the comprehensive balance of wheel load, adhesion and energy recovery, which can easily lead to insufficient resource utilization or reduced vehicle control performance. 4. Insufficient system response speed and adaptability: Traditional hydraulic electronic stability control systems respond slowly and cannot quickly respond to dynamic changes under extreme working conditions. In addition, existing energy recovery systems and dynamic control systems are mostly fixed structures, lacking the flexibility to adapt to multiple scenarios (such as complex curves or ramps).

[0047] In the related art, active yaw control, ABS (Anti-lock Braking System) and drive anti-skid control are integrated to control the vehicle's tilt and sideslip, but the main focus is on the multi-parameter fusion in vehicle stability control and the integrated control of AYC (Active Yaw Control), ABS, and ASR (Acceleration Slip Regulation), without considering the coordinated problem of the driving torque of each motor and the energy recovery and torque distribution. In the related art, each staged balance control (motor driving torque and hydraulic braking torque) is also used to optimize the vehicle's response speed, but the coordinated problem of energy recovery and torque distribution is not considered. Based on this, the present application provides a vehicle control method, which determines the target braking force and target driving force of each wheel respectively through the target yaw torque and the load of each wheel, combines the motor regenerative braking torque with the vehicle's yaw torque demand, and realizes the optimized coordinated design of energy recovery and dynamic torque distribution, while improving the dynamic stability of the vehicle and the energy recovery efficiency of the vehicle during braking.

[0048] Figure 1 A vehicle control method is provided as an exemplary embodiment of the present application, and the control method includes:

[0049] S11. Obtaining operating parameters of the vehicle.

[0050] The operating parameters of the vehicle are real-time data of the vehicle during operation. The operating parameters include the load of each wheel of the vehicle, such as the vertical load of each wheel, indicating the force acting in the vertical direction of the wheel. The operating parameters may also include the wheel speed, longitudinal acceleration, longitudinal speed, vehicle speed, current output torque of each motor, speed, battery power, etc. The operating parameters of the vehicle may be obtained through sensors on the vehicle.

[0051] S12. Determine a target yaw moment of the vehicle according to operating parameters of the vehicle.

[0052] During the operation of the vehicle, the vehicle's operating parameters and environmental information are collected in real time, such as ground friction coefficient, slope, curve radius, etc., and the vehicle's target yaw moment is determined based on the vehicle's operating parameters and environmental information.

[0053] In order to adjust the angular velocity of the vehicle on the curve in real time and avoid the risk of side slip when the vehicle is turning, in one embodiment, the operating parameters of the vehicle include the current position of the vehicle, the front wheel angle, the actual yaw rate, and the longitudinal speed;

[0054] Then, the target yaw moment of the vehicle is determined according to the operating parameters of the vehicle, including:

[0055] Determining a target yaw rate of the vehicle based on a preset first correspondence between the longitudinal speed, the actual yaw rate, the wheelbase of the vehicle, the front wheel turning angle, and the radius of curvature of the curve; wherein the radius of curvature of the curve indicates the radius of curvature of the road at the current position of the vehicle;

[0056] The target yaw moment of the vehicle is determined based on a preset second correspondence between the moment of inertia of the vehicle about a preset coordinate system, the target yaw rate, and the actual yaw rate.

[0057] Among them, the front wheel turning angle of the vehicle is the turning angle of the front wheel of the vehicle relative to the longitudinal axis of the vehicle, the curve curvature radius indicates the road curvature radius of the vehicle at the current position, and the moment of inertia of the vehicle around the preset coordinate system can be the moment of inertia of the vehicle around the center of mass.

[0058] The calculation method of the target yaw moment is further explained below in conjunction with a specific formula.

[0059] After determining the longitudinal speed, actual yaw rate, vehicle wheelbase, front wheel turning angle and curve radius, the target yaw rate of the vehicle can be obtained. The target yaw rate of the vehicle is the rate at which the vehicle rotates around the vertical axis of the vehicle body. It represents the rotation speed of the vehicle body relative to its direction of movement when turning or changing lanes, and reflects the lateral stability of the vehicle when turning or changing lanes. tar Through the preset first correspondence We get, where ω tar is the target yaw rate, V x is the longitudinal speed of the vehicle, δ is the front wheel turning angle of the vehicle, L is the wheelbase of the vehicle, K is the stability gain factor, which is used to adjust the target yaw response when driving on a curve, and R is the radius of curvature of the curve. By adding the radius of curvature of the curve to calculate the target yaw rate, the angular velocity of the vehicle when cornering can be considered, and the angular velocity of the vehicle can be adjusted in real time to avoid the vehicle from skidding.

[0060] After the target yaw rate is obtained, the target yaw moment can be obtained through the preset second corresponding relationship between the moment of inertia of the vehicle around the preset coordinate system, the target yaw rate and the actual yaw rate. The preset second corresponding relationship is M tar =I Z (φ tar -φ), where M tar is the target yaw moment, I Z is the moment of inertia of the vehicle about its center of mass, is the target yaw rate, is the actual yaw rate of the vehicle.

[0061] S13: Based on the target yaw moment and the load of each wheel, determine the target braking force and the target driving force of each wheel respectively.

[0062] Based on the target yaw moment and the load of each wheel, different target braking forces and target driving forces are respectively allocated to each wheel. To address the problem of limited regenerative braking torque of the motor in the existing system, the embodiment of the present application dynamically adjusts the regenerative braking torque distribution, combines the motor regenerative braking torque with the yaw moment requirement of the vehicle, gives priority to the use of regenerative braking torque, increases the energy recovery efficiency of the vehicle, establishes a balance between yaw stability and energy recovery, and achieves a dual improvement in vehicle stability and energy efficiency.

[0063] In one embodiment, based on the target yaw moment and the load of each vehicle, the target braking force and the target driving force of each wheel are determined respectively, including:

[0064] Determining the energy recovery power of each wheel based on the load of each wheel; wherein the energy recovery power indicates the power of converting the kinetic energy of the wheel into electrical energy and storing it in the battery of the vehicle;

[0065] determining an initial braking force of each wheel based on the energy recovery power of each wheel;

[0066] Determine a target driving force for each wheel based on the target yaw moment;

[0067] The target braking force is determined based on the initial braking force and the vehicle's energy recovery efficiency; wherein the energy recovery efficiency indicates the proportion of energy converted into electrical energy from the vehicle's kinetic energy and stored in the battery, the energy recovery efficiency is determined based on the regenerative braking force of each wheel, and the regenerative braking force is determined based on the operating data of the motor corresponding to each wheel.

[0068] The load on each wheel can be determined by collecting the vehicle's operating parameters, and then the wheel load distribution can be calculated. z，i Calculate the load proportion of each wheel, in, is the total vertical load on all wheels, F z，i is the vertical load on wheel i, W i is the load ratio of wheel i, and then the load ratio of each wheel W i Determine the vertical load of wheel i, determine the energy recovery power of each wheel according to the vertical load of each wheel, then determine the initial braking force of each wheel based on the energy recovery power of each wheel, determine the target driving force of each wheel based on the target yaw moment, and finally determine the target braking force of each wheel according to the initial braking force and the energy recovery efficiency of the vehicle.

[0069] The target driving force is determined according to the target yaw moment. Among them, F x,left is the left wheel driving force of the vehicle, F x,right is the right wheel driving force of the vehicle, M tar is the target yaw moment, r is the wheel radius, F x,front is the front axle driving force of the vehicle, b is the distance from the center of mass of the vehicle to the rear axle, L is the wheelbase of the vehicle, and F x is the longitudinal force requirement of the vehicle, F x,rear is the rear axle driving force of the vehicle, a is the distance from the center of mass of the vehicle to the front axle, and the target driving force of the left and right wheels is adjusted according to the target yaw moment of the vehicle.

[0070] Among them, the real-time operation data of the motors corresponding to different wheels of the vehicle can be collected to determine the regenerative braking torque of each wheel, and then Get the energy recovery power threshold of wheel i, where T re is the regenerative braking torque threshold for each wheel, P re，i is the energy recovery power threshold of wheel i, ωi is the angular velocity of wheel i, and the total energy recovery efficiency of the vehicle is obtained according to the regenerative braking torque of each wheel. γ re The energy recovery efficiency of the vehicle, is the sum of the energy recovery power of the wheels, P total is the total energy recovery power of the vehicle. And the energy recovery power threshold P of each wheel re，i Limited by the vehicle's battery charging power, P re，i ≤P max , P max Maximum charging power for the vehicle's battery.

[0071] In one embodiment, based on the load of each wheel, determining the energy recovery power of each wheel includes:

[0072] In response to the vertical load of the first wheel being greater than the vertical load of the second wheel, determining to distribute the total energy recovery power of the vehicle to the first wheel until the energy recovery power of the first wheel reaches a first recovery power threshold; wherein the total energy recovery power indicates the total power of converting kinetic energy of the vehicle into electrical energy and storing it in the battery, the total energy recovery power is determined according to the regenerative braking torque of each wheel, and the first recovery power threshold is determined according to a charging threshold of the vehicle;

[0073] The allocated total energy recovery power is allocated to the second wheel until the energy recovery power of the second wheel reaches a second recovery power threshold; wherein the second recovery power threshold is determined according to a charging threshold of the vehicle.

[0074] According to the load ratio of the wheels, the vertical load of each wheel can be obtained. If the vertical load of the first wheel is greater than the vertical load of the second wheel, the first wheel is the object of priority energy recovery, and the vehicle's VCU (Vehicle Control Unit) preferentially allocates the total energy recovery power of the vehicle to the first wheel until the energy recovery power of the first wheel reaches a first recovery power threshold. The first recovery power threshold is determined according to the charging threshold of the vehicle and can be P re，i =min(T re,i ·ω i ,P max ), where P re，i is the energy recovery power threshold of wheel i, T re,i is the regenerative braking torque threshold of the i-th wheel, ω i is the angular velocity of wheel i, P max The total energy recovery power indicates the total power of converting the vehicle's kinetic energy into electrical energy and storing it in the battery. The total energy recovery power is determined based on the regenerative braking torque of each wheel. γre The energy recovery efficiency of the vehicle, is the sum of the energy recovery power of the wheels, P total is the total energy recovery power of the vehicle, and P re，i ≤P max , P re，i is the energy recovery power threshold of the i-th wheel, for example, P re，1 is the first recovery power threshold of the first wheel, P re，2 is the second recovery power threshold of the second wheel, P max Maximum charging power for the vehicle's battery.

[0075] When the energy recovery power of the first wheel reaches the first recovery power threshold, the total energy recovery power after allocation is allocated to the second wheel until the energy recovery power of the second wheel reaches the second recovery power threshold. It can be understood that the second wheel is the secondary priority wheel. For example, among the four tires of the vehicle, the order of the vertical load of the wheels is vertical load of the first wheel>vertical load of the second wheel>vertical load of the third wheel>vertical load of the fourth wheel. At this time, the priority order of the total energy recovery power allocation of the vehicle is first wheel→second wheel→third wheel→fourth wheel.

[0076] In one embodiment, determining the target braking force according to the initial braking force and the energy recovery efficiency of the vehicle includes:

[0077] The target braking force is determined according to a preset third corresponding relationship among the initial braking force, the energy recovery efficiency, the driving torque of each wheel and the vertical load of each wheel; wherein the vertical load of each wheel is determined according to the longitudinal force of each wheel, and the longitudinal force of each wheel is determined according to the target yaw moment.

[0078] After the initial braking force is obtained, the target braking force can be determined according to a preset third correspondence relationship among the initial braking force, the energy recovery efficiency, the driving torque of each wheel, and the vertical load of each wheel. The third correspondence relationship is: Among them, J is the objective function, T re,i is the regenerative braking torque threshold of the i-th wheel, μ is the ground adhesion coefficient, F z,i is the vertical load of the i-th wheel, λ is the energy recovery weight coefficient, γ re is the energy recovery efficiency of the vehicle. According to the constraints, the objective function J is solved, and the regenerative braking torque and energy recovery power are coordinated and optimized to obtain the maximum energy recovery efficiency γ of the vehicle. re , finally according to and γ re / r=F re The total braking force generated by the vehicle's energy recovery is obtained, that is, the target braking force F reThe objective function is solved by constraints to maximize the energy recovery efficiency while maintaining the stability of the vehicle.

[0079] Among them, in the third corresponding relationship, the vertical load of each wheel is determined according to the longitudinal force of each wheel, and the longitudinal force of each wheel is determined according to the target yaw moment, which can be understood as the constraint conditions including: M tar is the target yaw moment, F x，i is the longitudinal force of the i-th wheel, r is the wheel radius, F y，i is the lateral force of the i-th wheel, μ is the ground adhesion coefficient, F z,i is the vertical load of the i-th wheel, m is the vehicle mass, V x is the vehicle longitudinal velocity, is the actual yaw rate of the vehicle.

[0080] S14: driving the vehicle according to the target braking force and the target driving force.

[0081] After obtaining the target braking force and the target driving force of the vehicle, the vehicle is driven to travel according to the target braking force and the target driving force. However, in certain cases, the regenerative braking torque is insufficient and the vehicle cannot reach the expected driving target. Therefore, in one embodiment, the vehicle is driven to travel according to the target braking force and the target driving force, including:

[0082] In response to the target braking force being less than the braking force corresponding to the target yaw moment, obtaining a compensatory braking force generated by the hydraulic braking force of the vehicle; wherein the sum of the target braking force and the supplementary braking force is the braking force corresponding to the target yaw moment;

[0083] The vehicle is driven according to the target braking force, the supplementary braking force and the target driving force.

[0084] When the target braking force of the vehicle is less than the braking force corresponding to the target yaw moment, the hydraulic brake provides a compensatory braking force, F total =F re +F λy , Among them, F total is the total braking force required by the vehicle, F λy is the compensating braking force of the hydraulic brake, V x is the longitudinal velocity of the vehicle, F re is the target braking force, P re It is the energy recovery power of the vehicle. When the motor feedback capacity is insufficient, the hydraulic brake automatically compensates for the missing torque to ensure the dynamic control requirements of the vehicle.

[0085] The embodiments of the present application address the problem of limited regenerative braking torque of the motor in the existing system by dynamically adjusting the distribution of the regenerative braking torque to give priority to the wheels with larger loads, thereby maximizing the regenerative power, giving priority to the regenerative braking torque, and reducing the reliance on hydraulic brakes, thereby extending the brake life and improving the vehicle's endurance.

[0086] The embodiment of the present application introduces an objective function to maximize the energy recovery efficiency while satisfying the vehicle's stability. Through the coordinated control strategy of energy recovery and dynamic torque distribution, the motor regenerative braking torque is combined with the vehicle's yaw torque requirement. Through the coordinated optimization of energy recovery and dynamic torque distribution, the vehicle's stability and energy efficiency are both improved, a balance is established between yaw stability and energy recovery, and the vehicle's energy utilization efficiency during braking is improved.

[0087] The embodiments of the present application also take into account the vehicle's yaw stability, adhesion limit and energy recovery efficiency, ensuring that the vehicle can achieve optimal performance under various working conditions. At the same time, the rapid adjustment characteristics of the motor drive torque are used to significantly improve the response speed of the system, so that it can better adapt to the needs of extreme working conditions. In addition, the system architecture of the embodiments provided by the present application supports the adaptation of multiple working conditions (such as slippery roads and complex curves), and can dynamically adjust the torque distribution strategy by real-time perception of vehicle status and environmental information.

[0088] Combine the following Figure 2 , further explain the vehicle control method:

[0089] First, the vehicle's operating parameters are collected, such as the vehicle's wheel speed, longitudinal acceleration, longitudinal speed, vehicle speed, the current output torque of each motor, speed, battery power, the load of each wheel of the vehicle, etc., and environmental information is collected, such as the ground friction coefficient, slope, curve radius, etc., and then the target yaw rate is calculated. Among them, ω tar is the target yaw rate, V x is the longitudinal speed of the vehicle, δ is the front wheel turning angle of the vehicle, L is the wheelbase of the vehicle, K is the stability gain factor, which is used to adjust the target yaw response when driving on a curve, and R is the radius of curvature of the curve. After obtaining the target yaw rate, the target yaw moment can be obtained through the preset second correspondence between the moment of inertia of the vehicle around the preset coordinate system, the target yaw rate and the actual yaw rate. The preset second correspondence is M tar =I Z (φ tar -φ), where M tar is the target yaw moment, I Z is the moment of inertia of the vehicle about its center of mass, is the target yaw rate, is the actual yaw rate of the vehicle.

[0090] Next, the load on each wheel can be determined by the collected vehicle operating parameters, and then the load distribution of the wheel can be calculated. z，i Calculate the load proportion of each wheel, in, is the total vertical load on all wheels, F z，i is the vertical load on wheel i, W i is the load ratio of wheel i, and then the load ratio of each wheel W i Determine the vertical load of wheel i. According to the load ratio of the wheels, the vertical load of each wheel can be obtained. If the vertical load of the first wheel is greater than the vertical load of the second wheel, the first wheel is the object of priority energy recovery, and the total energy recovery power of the vehicle is preferentially allocated to the first wheel until the energy recovery power of the first wheel reaches the first recovery power threshold. The first recovery power threshold is determined according to the charging threshold of the vehicle and can be P re，i =min(T re,i ·ω i ,P max ), where P re，i is the energy recovery power threshold of wheel i, T re,i is the regenerative braking torque threshold of the i-th wheel, ω i is the angular velocity of wheel i, P max The total energy recovery power indicates the total power of converting the vehicle's kinetic energy into electrical energy and storing it in the battery. The total energy recovery power is determined based on the regenerative braking torque of each wheel. γ re The energy recovery efficiency of the vehicle, is the sum of the energy recovery power of the wheels, P total is the total energy recovery power of the vehicle, and P re，i ≤P max , P re，i is the energy recovery power threshold of the i-th wheel, for example, P re，1 is the first recovery power threshold of the first wheel, P re，2 is the second recovery power threshold of the second wheel, P max Maximum charging power for the vehicle's battery.

[0091] When the energy recovery power of the first wheel reaches the first recovery power threshold, the total energy recovery power after allocation is allocated to the second wheel until the energy recovery power of the second wheel reaches the second recovery power threshold. It can be understood that the second wheel is the secondary priority wheel. For example, among the four tires of the vehicle, the order of the vertical load of the wheels is vertical load of the first wheel>vertical load of the second wheel>vertical load of the third wheel>vertical load of the fourth wheel. At this time, the priority order of the total energy recovery power allocation of the vehicle is first wheel→second wheel→third wheel→fourth wheel.

[0092] The regenerative braking torque of each wheel can be determined by first collecting the real-time operation data of the motors corresponding to the different wheels of the vehicle, and then Get the energy recovery power threshold of wheel i, where T re is the regenerative braking torque threshold for each wheel, P re，i is the energy recovery power threshold of wheel i, ω i is the angular velocity of wheel i, and the total energy recovery efficiency of the vehicle is obtained according to the regenerative braking torque of each wheel. γ re The energy recovery efficiency of the vehicle, is the sum of the energy recovery power of the wheels, P total is the total energy recovery power of the vehicle. And the energy recovery power threshold P of each wheel re，i Limited by the vehicle's battery charging power, P re，i ≤P max , P max Maximum charging power for the vehicle's battery.

[0093] The target driving force is determined according to the target yaw moment. Among them, F x,left is the left wheel driving force of the vehicle, F x,right is the right wheel driving force of the vehicle, M tar is the target yaw moment, r is the wheel radius, F x,front is the front axle driving force of the vehicle, b is the distance from the center of mass of the vehicle to the rear axle, L is the wheelbase of the vehicle, and F x is the longitudinal force requirement of the vehicle, F x,rear is the rear axle driving force of the vehicle, a is the distance from the center of mass of the vehicle to the front axle, and the target driving force of the left and right wheels is adjusted according to the target yaw moment of the vehicle.

[0094] After the initial braking force is obtained, the target braking force can be determined according to a preset third correspondence relationship among the initial braking force, the energy recovery efficiency, the driving torque of each wheel, and the vertical load of each wheel. The third correspondence relationship is: Among them, J is the objective function, T re,iis the regenerative braking torque threshold of the i-th wheel, μ is the ground adhesion coefficient, F z,i is the vertical load of the i-th wheel, λ is the energy recovery weight coefficient, γ re is the energy recovery efficiency of the vehicle. According to the constraints, the objective function J is solved, and the regenerative braking torque and energy recovery power are coordinated and optimized to obtain the maximum energy recovery efficiency γ of the vehicle. re , finally according to and γ re / r=F re The total braking force generated by the vehicle's energy recovery is obtained, that is, the target braking force F re The objective function is solved by constraints to maximize the energy recovery efficiency while maintaining the stability of the vehicle.

[0095] Among them, in the third corresponding relationship, the vertical load of each wheel is determined according to the longitudinal force of each wheel, and the longitudinal force of each wheel is determined according to the target yaw moment, which can be understood as the constraint conditions including: M tar is the target yaw moment, F x，i is the longitudinal force of the i-th wheel, r is the wheel radius, F y，i is the lateral force of the i-th wheel, μ is the ground adhesion coefficient, F z,i is the vertical load of the i-th wheel, m is the vehicle mass, V x is the vehicle longitudinal velocity, is the actual yaw rate of the vehicle.

[0096] The vehicle is driven according to the target braking force and the target driving force. However, when the target braking force of the vehicle is less than the braking force corresponding to the target yaw moment, the hydraulic brake provides a compensating braking force, F total =F re +F λy , Among them, F total is the total braking force required by the vehicle, F λy is the compensating braking force of the hydraulic brake, V x is the longitudinal velocity of the vehicle, F re is the target braking force, P re It is the energy recovery power of the vehicle. When the motor feedback capacity is insufficient, the hydraulic brake automatically compensates for the missing torque to ensure the dynamic control requirements of the vehicle.

[0097] It should be understood that although Figure 1-2 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1-2 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0098] like Figure 3 As shown, the present application also provides a vehicle control system, the control system comprising:

[0099] An acquisition module 31 is used to acquire the operating parameters of the vehicle; wherein the operating parameters include the load of each wheel of the vehicle;

[0100] A first determination module 32, configured to determine a target yaw moment of the vehicle according to an operating parameter of the vehicle;

[0101] a second determining module 33, configured to determine a target braking force and a target driving force of each wheel based on the target yaw moment and the load of each wheel;

[0102] The driving module 34 is used to drive the vehicle to travel according to the target braking force and the target driving force.

[0103] In one embodiment, the operating parameters include the current position of the vehicle, the front wheel angle, the actual yaw rate, and the longitudinal speed;

[0104] Then the first determining module 32 is further used for:

[0105] determining a target yaw rate of the vehicle based on a preset first correspondence among the longitudinal speed, the actual yaw rate, the wheelbase of the vehicle, the front wheel turning angle, and a curve curvature radius, the curve curvature radius indicating a road curvature radius of the vehicle at the current position;

[0106] A target yaw moment of the vehicle is determined based on a preset second corresponding relationship among the rotational inertia of the vehicle around a preset coordinate system, the target yaw rate, and the actual yaw rate.

[0107] In one embodiment, the second determining module 33 is further configured to:

[0108] determining the energy recovery power of each wheel based on the load of each wheel; the energy recovery power indicates the power of converting the kinetic energy of the wheel into electrical energy and storing it in the battery;

[0109] determining an initial braking force of each wheel based on the energy recovery power of each wheel;

[0110] determining a target driving force for each wheel based on the target yaw moment;

[0111] The target braking force is determined based on the initial braking force and the energy recovery efficiency of the vehicle; the energy recovery efficiency indicates the proportion of energy converted into electrical energy from the kinetic energy of the vehicle and stored in a battery, the energy recovery efficiency is determined based on the regenerative braking torque of each wheel, and the regenerative braking torque is determined based on the operating data of the motor corresponding to each wheel.

[0112] In one embodiment, the second determining module 33 is further configured to:

[0113] In response to the vertical load of the first wheel being greater than the vertical load of the second wheel, determining to distribute the total energy recovery power of the vehicle to the first wheel until the energy recovery power of the first wheel reaches a first recovery power threshold; wherein the total energy recovery power indicates the total power of converting kinetic energy of the vehicle into electrical energy and storing it in a battery, the total energy recovery power is determined according to the regenerative braking torque of each wheel, and the first recovery power threshold is determined according to a charging threshold of the vehicle;

[0114] The allocated total energy recovery power is allocated to the second wheel until the energy recovery power of the second wheel reaches a second recovery power threshold; wherein the second recovery power threshold is determined according to a charging threshold of the vehicle.

[0115] In one embodiment, the second determining module 33 is further configured to:

[0116] The target braking force is determined according to a preset third corresponding relationship among the initial braking force, the energy recovery efficiency, the driving torque of each wheel and the vertical load of each wheel; wherein the vertical load of each wheel is determined according to the longitudinal force of each wheel, and the longitudinal force of each wheel is determined according to the target yaw moment.

[0117] In one embodiment, the driving module 34 is further configured to:

[0118] In response to the target braking force being less than the braking force corresponding to the target yaw moment, obtaining a compensatory braking force generated by the hydraulic braking force of the vehicle; wherein the sum of the target braking force and the supplementary braking force is the braking force corresponding to the target yaw moment;

[0119] The vehicle is driven to travel according to the target braking force, the supplementary braking force, and the target driving force.

[0120] For the system embodiment, since it basically corresponds to the method embodiment, the relevant parts can refer to the partial description of the method embodiment. The system embodiment described above is only illustrative, wherein the units described as separate components may or may not be physically separated, and the components as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present application solution.

[0121] Figure 4 This is a structural diagram of an electronic device shown in an example embodiment of the present application, the electronic device includes a memory, a processor, and a computer program stored in the memory and used to run on the processor, and the processor implements the control method described in any of the above embodiments when executing the computer program. Figure 4 The electronic device 40 shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0122] like Figure 4 As shown, the electronic device 40 may be in the form of a general-purpose computing device, for example, it may be a server device. The components of the electronic device 40 may include, but are not limited to: at least one processor 41, at least one memory 42, and a bus 43 connecting different system components (including the memory 42 and the processor 41).

[0123] The bus 43 includes a data bus, an address bus, and a control bus.

[0124] The memory 42 may include a volatile memory, such as a random access memory (RAM) 421 and / or a cache memory 422 , and may further include a read-only memory (ROM) 423 .

[0125] The memory 42 may also include a program tool 425 (or utility) having a set (at least one) of program modules 424, such program modules 424 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0126] The processor 41 executes various functional applications and data processing by running the computer program stored in the memory 42, such as the control method provided in any of the above embodiments.

[0127] The electronic device 40 may also communicate with one or more external devices 44 (e.g., keyboards, pointing devices, etc.). Such communication may be performed via an input / output (I / O) interface 45. Furthermore, the electronic device 40 may also communicate with one or more networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks, such as the Internet) via a network adapter 46. As shown, the network adapter 46 communicates with other modules of the electronic device 40 via a bus 43. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device 40, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID (disk array) systems, tape drives, and data backup storage systems, etc.

[0128] It should be noted that although several units / modules or sub-units / modules of the electronic device are mentioned in the above detailed description, this division is merely exemplary and not mandatory. In fact, according to the embodiments of the present application, the features and functions of two or more units / modules described above can be embodied in one unit / module. Conversely, the features and functions of one unit / module described above can be further divided into multiple units / modules to be embodied.

[0129] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, and when the program is executed by a processor, the control method provided in any of the above embodiments is implemented.

[0130] The readable storage medium may include but is not limited to: a portable disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical storage device, a magnetic storage device or any suitable combination of the above.

[0131] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0132] An embodiment of the present application also provides a computer program product, including a computer program, which implements any of the control methods described above when executed by a processor.

[0133] Among them, the program code for executing the computer program product of the present application can be written in any combination of one or more programming languages, and the program code can be executed completely on the user device, partially on the user device, as an independent software package, partially on the user device and partially on a remote device, or completely on the remote device.

[0134] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0135] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A vehicle control method, characterized in that: The control method comprises: Acquiring operating parameters of the vehicle; wherein the operating parameters include the load of each wheel of the vehicle; determining a target yaw moment of the vehicle according to an operating parameter of the vehicle; Based on the target yaw moment and the load of each wheel, respectively determine a target braking force and a target driving force of each wheel; The vehicle is driven to travel according to the target braking force and the target driving force.

2. The control method according to claim 1, characterized in that: The operating parameters include the current position of the vehicle, the front wheel angle, the actual yaw rate, and the longitudinal speed; Then, determining the target yaw moment of the vehicle according to the operating parameters of the vehicle includes: determining a target yaw rate of the vehicle based on a preset first correspondence among the longitudinal speed, the actual yaw rate, the wheelbase of the vehicle, the front wheel turning angle, and a curve curvature radius, the curve curvature radius indicating a road curvature radius of the vehicle at the current position; A target yaw moment of the vehicle is determined based on a preset second corresponding relationship among the rotational inertia of the vehicle around a preset coordinate system, the target yaw rate, and the actual yaw rate.

3. The control method according to claim 1, characterized in that: The step of determining the target braking force and the target driving force of each wheel based on the target yaw moment and the load of each wheel comprises: determining the energy recovery power of each wheel based on the load of each wheel; the energy recovery power indicates the power of converting the kinetic energy of the wheel into electrical energy and storing it in the battery; determining an initial braking force of each wheel based on the energy recovery power of each wheel; determining a target driving force for each wheel based on the target yaw moment; The target braking force is determined based on the initial braking force and the energy recovery efficiency of the vehicle; the energy recovery efficiency indicates the proportion of energy converted into electrical energy from the kinetic energy of the vehicle and stored in a battery, the energy recovery efficiency is determined based on the regenerative braking torque of each wheel, and the regenerative braking torque is determined based on the operating data of the motor corresponding to each wheel.

4. The control method according to claim 3, characterized in that: The determining the energy recovery power of each wheel based on the load of each wheel comprises: In response to the vertical load of the first wheel being greater than the vertical load of the second wheel, determining to distribute the total energy recovery power of the vehicle to the first wheel until the energy recovery power of the first wheel reaches a first recovery power threshold; wherein the total energy recovery power indicates the total power of converting kinetic energy of the vehicle into electrical energy and storing it in a battery, the total energy recovery power is determined according to the regenerative braking torque of each wheel, and the first recovery power threshold is determined according to a charging threshold of the vehicle; The allocated total energy recovery power is allocated to the second wheel until the energy recovery power of the second wheel reaches a second recovery power threshold; wherein the second recovery power threshold is determined according to a charging threshold of the vehicle.

5. The control method according to claim 3, characterized in that: The determining the target braking force according to the initial braking force and the energy recovery efficiency of the vehicle includes: The target braking force is determined according to a preset third corresponding relationship among the initial braking force, the energy recovery efficiency, the driving torque of each wheel and the vertical load of each wheel; wherein the vertical load of each wheel is determined according to the longitudinal force of each wheel, and the longitudinal force of each wheel is determined according to the target yaw moment.

6. The control method according to any one of claims 1 to 5, characterized in that: The step of driving the vehicle to travel according to the target braking force and the target driving force includes: In response to the target braking force being less than the braking force corresponding to the target yaw moment, obtaining a compensatory braking force generated by the hydraulic braking force of the vehicle; wherein the sum of the target braking force and the supplementary braking force is the braking force corresponding to the target yaw moment; The vehicle is driven to travel according to the target braking force, the supplementary braking force, and the target driving force.

7. A vehicle control system, characterized in that: The control system comprises: An acquisition module, used for acquiring operating parameters of the vehicle; wherein the operating parameters include the load of each wheel of the vehicle; A first determination module, configured to determine a target yaw moment of the vehicle according to an operating parameter of the vehicle; a second determination module, configured to determine a target braking force and a target driving force of each wheel based on the target yaw moment and the load of each wheel; A driving module is used to drive the vehicle to travel according to the target braking force and the target driving force.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and used to run on the processor, characterized in that: When the processor executes the computer program, the control method according to any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the control method according to any one of claims 1 to 6 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the control method according to any one of claims 1 to 6 is implemented.

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