Vehicle torque control method and device, vehicle and storage medium

Abstract

The invention relates to a vehicle torque vector control method and device, a vehicle and a storage medium, and the method comprises the steps that the target yaw velocity of the vehicle is calculated; when the vehicle meets the preset rear axle torque vector control condition, the differential torque limiting range of the vehicle is determined by using the control parameter boundary constraint of the vehicle, and the yaw velocity closed-loop control differential torque is calculated in combination with the target yaw velocity; whether the vehicle meets a preset side slip angle limiting activation condition or not is judged through the side slip angle, the side slip angle closed-loop control differential torque of the vehicle is obtained in combination with the judgment result and the differential torque limiting range, then the target differential torque of the vehicle is calculated, and the vehicle is controlled based on the target differential torque. And the torque vector control of the vehicle meets the preset smooth control condition. Therefore, the technical problems that in the related technology, it is difficult to achieve the expected yaw velocity of a driver by distributing the driving force according to the adhesion capacity of all the wheels, the smoothness is poor during steering, and the driving experience of the driver cannot be improved easily are solved.

Description

Technical Field

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

[0002] Vehicle steering can be categorized as oversteer, understeer, or neutral steering. Understeer occurs when the vehicle's actual turning radius is larger than the driver's intended radius, making it difficult for the vehicle to turn along the intended trajectory. While this improves handling stability, it also reduces the vehicle's ability to avoid obstacles.

[0003] In the related art, although there is a technical solution for determining the torque distribution ratio of each driving vehicle through dynamic load, distributing the driving force according to the adhesion ability of each wheel will result in the driver's desired yaw angular velocity not being achieved, reducing the controllability. When the vehicle turns, the smoothness is poor, there is a sense of frustration or sudden change in the body posture, which affects the driver's driving experience. Summary of the Invention

[0004] The present application provides a vehicle torque control method, device, vehicle and storage medium to solve the technical problems in related technologies that allocating driving force according to the adhesion capacity of each wheel is difficult to achieve the driver's desired yaw angular velocity, the smoothness during steering is poor, and it is not conducive to improving the driver's driving experience.

[0005] A first aspect of the present application provides a vehicle torque vectoring control method, comprising the following steps: obtaining a torque control parameter of a vehicle, and judging whether the vehicle satisfies a preset rear axle torque vectoring control condition based on the torque control parameter, and calculating a target yaw rate of the vehicle using the torque control parameter; if the preset rear axle torque vectoring control condition is satisfied, determining a torque limit range of the vehicle using the control parameter boundary constraint of the vehicle, and calculating a yaw rate closed-loop control torque in combination with the target yaw rate and the torque limit range; obtaining a center of mass slip angle of the vehicle, judging whether the vehicle satisfies a preset center of mass slip angle limitation activation condition using the center of mass slip angle, and obtaining a judgment result, and obtaining a center of mass slip angle closed-loop control torque of the vehicle in combination with the judgment result and the torque limit range; and calculating a target torque of the vehicle in combination with the yaw rate closed-loop control torque and the center of mass slip angle closed-loop control torque, so as to control the vehicle based on the target torque so that the torque vectoring control of the vehicle satisfies a preset smooth control condition.

[0006] According to the above technical means, the embodiment of the present application can determine whether it is necessary to enable rear axle torque vectoring control based on the torque control parameters. If it is necessary to enable rear axle torque vectoring control, it is confirmed whether to activate the yaw rate closed-loop control torque difference through the real-time calculated target yaw rate, and it is determined whether to actively suppress sideslip through the center of mass sideslip angle. If active suppression is required, the target torque difference is calculated by combining the yaw rate closed-loop control torque difference and the center of mass sideslip angle closed-loop control torque difference to achieve smooth control of the vehicle and improve the driver's driving experience.

[0007] Optionally, in one embodiment of the present application, the preset rear axle torque vector control condition includes: the gear position of the vehicle is the forward gear; the current speed of the vehicle is within a preset speed range; the steering wheel angle of the vehicle is greater than a preset angle threshold, wherein the preset angle threshold is determined by the current vehicle speed; the steering wheel angle condition of the vehicle is provided with hysteresis.

[0008] According to the above technical means, the embodiment of the present application can determine whether it is necessary to enable rear axle torque vectoring control according to the rear axle torque vectoring control conditions to ensure the lateral movement capability of the vehicle.

[0009] Optionally, in one embodiment of the present application, the use of the vehicle's control parameter boundary constraints to determine the vehicle's torque limit range includes: judging whether the vehicle is in a preset low-speed driving condition based on the torque control parameters; if the vehicle is in the preset low-speed driving condition, enabling a torque limit flag when the vehicle is in a preset slip scenario; reducing the initial target torque at a preset gradient until it drops to an actual responsive value of the vehicle; and determining the torque limit range based on the actual responsive value, energy consumption constraints, and actuator capability constraints of the vehicle.

[0010] According to the above technical means, the embodiment of the present application can lock the working conditions that require torque limitation, enable the torque limitation flag under the corresponding working conditions, and then constrain the torque limitation range in combination with energy consumption, actuator capability, etc., to prevent oversteering and loss of control, etc., and ensure driving safety.

[0011] Optionally, in one embodiment of the present application, before calculating the yaw rate closed-loop control torque in combination with the target yaw rate and the torque limit range, it also includes: identifying the steering state of the vehicle based on the torque control parameter; judging whether the vehicle meets the preset yaw rate control activation condition based on the steering state; if the preset yaw rate control activation condition is met, calculating the yaw rate closed-loop control torque in combination with the target yaw rate and the torque limit range.

[0012] According to the above technical means, the embodiment of the present application can determine whether to activate the yaw rate closed-loop control torque difference by comparing the real-time calculated target yaw rate with the actual steering state of the vehicle, thereby ensuring the steering safety of the vehicle.

[0013] Optionally, in one embodiment of the present application, the obtaining of the center of mass sideslip angle of the vehicle, using the center of mass sideslip angle to determine whether a preset center of mass sideslip angle limit activation condition is satisfied, obtaining a judgment result, and combining the judgment result with the differential torque limit range to obtain the center of mass sideslip angle closed-loop control differential torque of the vehicle, includes: obtaining the tire-road friction coefficient of the vehicle; matching a corresponding center of mass sideslip angle threshold based on the tire-road friction coefficient; if the absolute value of the center of mass sideslip angle is greater than the absolute value of the center of mass sideslip angle threshold, determining the center of mass sideslip angle closed-loop control differential torque by proportional-integral-differential control based on the difference between the center of mass sideslip angle and the center of mass sideslip angle threshold and the current vehicle speed; otherwise, determining the center of mass sideslip angle closed-loop control differential torque to be zero.

[0014] According to the above technical means, the embodiment of the present application can use the closed-loop control torque difference of the center of mass sideslip angle as a stability guarantee. When the center of mass sideslip angle approaches the physical limit, the closed-loop control torque difference of the center of mass sideslip angle is adjusted so that the final target torque difference can achieve smoother vehicle control.

[0015] A second aspect of the present application provides a vehicle torque vectoring control device, comprising: an acquisition module for acquiring a torque control parameter of a vehicle, and judging whether the vehicle satisfies a preset rear axle torque vectoring control condition based on the torque control parameter, and calculating a target yaw rate of the vehicle using the torque control parameter; a first calculation module for determining a torque limit range of the vehicle using a control parameter boundary constraint of the vehicle when the preset rear axle torque vectoring control condition is satisfied, and calculating a yaw rate closed-loop control torque difference in combination with the target yaw rate and the torque limit range; a first judgment module for acquiring a center of mass slip angle of the vehicle, judging whether the vehicle satisfies a preset center of mass slip angle limit activation condition using the center of mass slip angle, obtaining a judgment result, and combining the judgment result with the torque limit range to obtain a center of mass slip angle closed-loop control torque of the vehicle; and a control module for calculating a target torque difference of the vehicle in combination with the yaw rate closed-loop control torque and the center of mass slip angle closed-loop control torque, and controlling the vehicle based on the target torque difference so that the torque vectoring control of the vehicle satisfies a preset smooth control condition.

[0016] Optionally, in one embodiment of the present application, the preset rear axle torque vector control conditions include: the vehicle's gear is a forward gear; the vehicle's current speed is within a preset speed range; the vehicle's steering wheel angle is greater than a preset angle threshold, wherein the preset angle threshold is determined by the current vehicle speed; and the vehicle's steering wheel is provided with hysteresis.

[0017] Optionally, in one embodiment of the present application, the first calculation module includes: a judgment unit for judging whether the vehicle is in a preset low-speed driving condition based on the torque control parameter; an enabling unit for enabling a differential torque limit flag when the vehicle is in the preset low-speed driving condition and when the vehicle is in a preset slip scenario; an adjusting unit for reducing the initial target differential torque at a preset gradient until it reaches an actual responsive value of the vehicle; and a first determination unit for determining the differential torque limit range based on the actual responsive value, energy consumption constraints and actuator capability constraints of the vehicle.

[0018] Optionally, in one embodiment of the present application, it also includes: an identification module for identifying the steering state of the vehicle based on the torque control parameter; a second judgment module for judging whether the vehicle meets the preset yaw rate control activation condition based on the steering state; and a second calculation module for calculating the yaw rate closed-loop control torque difference in combination with the target yaw rate and the torque difference limit range when the preset yaw rate control activation condition is met.

[0019] Optionally, in one embodiment of the present application, the judgment module includes: an acquisition unit for acquiring the tire-road friction coefficient of the vehicle; a matching unit for matching a corresponding center of mass sideslip angle threshold based on the tire-road friction coefficient; and a second determination unit for determining the center of mass sideslip angle closed-loop control torque difference by performing proportional-integral-differential control based on the difference between the center of mass sideslip angle and the center of mass sideslip angle threshold and the current vehicle speed when the absolute value of the center of mass sideslip angle is greater than the absolute value of the center of mass sideslip angle threshold; otherwise, determining that the center of mass sideslip angle closed-loop control torque difference is zero.

[0020] A third aspect of the present application provides a vehicle, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the vehicle torque vectoring control method as described in the above embodiment.

[0021] A fourth aspect of the present application provides a computer-readable storage medium, which stores computer instructions, and the computer instructions are used to enable the computer to execute the vehicle torque vector control method as described in the above embodiment.

[0022] The fifth aspect of the present application provides a computer program product, including a computer program, which, when executed, is used to implement the above vehicle torque vector control method.

[0023] The embodiments of the present application can determine whether to enable rear axle torque vectoring control based on torque control parameters. If rear axle torque vectoring control is required, the real-time calculated target yaw rate is used to confirm whether to activate the yaw rate closed-loop control torque differential. The center of mass sideslip angle is used to determine whether active sideslip suppression is required. If active sideslip suppression is required, the target torque differential is calculated by combining the yaw rate closed-loop control torque differential and the center of mass sideslip angle closed-loop control torque differential to achieve smooth vehicle control and enhance the driver's driving experience. This solves the technical problem in related technologies where allocating driving force based on the adhesion of each wheel makes it difficult to achieve the driver's desired yaw rate, resulting in poor steering smoothness and a detrimental effect on the driver's driving experience.

[0024] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0026] Figure 1 This is a flow chart of a vehicle torque vectoring control method provided according to an embodiment of the present application;

[0027] Figure 2 A schematic diagram of a vehicle power control principle provided according to one embodiment of the present application;

[0028] Figure 3 This is a flow chart of a vehicle torque vectoring control method provided according to one embodiment of the present application;

[0029] Figure 4 Schematic diagram of the structure of a vehicle torque vectoring control device provided according to an embodiment of the present application;

[0030] Figure 5 A schematic structural diagram of a vehicle provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0031] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0032] The following describes a vehicle torque vectoring control method, apparatus, vehicle, and storage medium according to embodiments of the present application with reference to the accompanying drawings. In response to the technical issues mentioned in the background art above, allocating driving force based on the adhesion of each wheel makes it difficult to achieve the driver's desired yaw rate, resulting in poor smoothness during steering and a detrimental effect on the driver's driving experience. The present application provides a vehicle torque vectoring control method. In this method, whether rear axle torque vectoring control should be enabled is determined based on a torque control parameter. If rear axle torque vectoring control is required, activation of a yaw rate closed-loop control torque difference is determined based on a real-time calculated target yaw rate, and active sideslip suppression is determined based on the center of mass sideslip angle. If active sideslip suppression is required, a target torque difference is calculated by combining the yaw rate closed-loop control torque difference and the center of mass sideslip angle closed-loop control torque difference to achieve smooth vehicle control and an improved driving experience. This solves the technical issues in the related art, where allocating driving force based on the adhesion of each wheel makes it difficult to achieve the driver's desired yaw rate, resulting in poor smoothness during steering and a detrimental effect on the driver's driving experience.

[0033] In related technologies, steering control relies on the driver's steering input and the passive intervention of the electronic stability program system. When the vehicle understeers, the electronic stability program generates a reverse yaw torque by braking the wheel on one side based on the wheel speed sensor and yaw rate signal to correct the trajectory. Although this mechanism can improve basic stability, it has systemic defects: braking intervention is not triggered until the understeer is fully manifested, and the correction action is significantly delayed, resulting in the actual turning radius being continuously larger than expected, making it impossible to avoid obstacles in time; braking intervention will instantly reduce driving force, causing a sudden drop in vehicle speed and body posture disturbance, which will undermine driving smoothness, especially in high-speed curves and easily cause vehicle instability; to avoid excessive corrections that cause tailspin, the electronic stability program system usually adopts a conservative strategy, sacrificing steering flexibility to prioritize stability. This makes it difficult for the vehicle to break through physical limits and restricts the maximum cornering speed under stable conditions.

[0034] The embodiments of the present application can overcome the above problems by integrating real-time dynamic boundary constraints and smooth control strategies.

[0035] Specifically, Figure 1 A schematic flow chart of a vehicle torque vectoring control method provided in an embodiment of the present application.

[0036] like Figure 1 As shown, the vehicle torque vectoring control method includes the following steps:

[0037] In step S101 , a torque control parameter of the vehicle is obtained, and whether the vehicle meets a preset rear axle torque vectoring control condition is determined based on the torque control parameter, and a target yaw rate of the vehicle is calculated using the torque control parameter.

[0038] During the actual implementation process, the embodiment of the present application can obtain the vehicle's torque control parameters, including gear position, vehicle speed, steering wheel angle, driver's required torque, etc., and then determine whether to enable the rear axle torque vectoring control flag based on the torque control parameters. Among them, the rear axle torque vectoring control can be used to improve the vehicle's handling, stability and cornering performance, especially in rear-wheel drive or four-wheel drive vehicles, and can actively and independently control the amount of torque transmitted to the left and right rear wheels, rather than just passively distributing torque like a traditional differential.

[0039] Furthermore, the target yaw rate is calculated as follows:

[0040]

[0041] Among them, v x is the longitudinal speed, δ f is the front wheel angle, which is obtained by looking up the steering wheel angle table, μ is the tire-road friction coefficient, L is the wheelbase, and λ is the safety factor. is the stability factor, F m is the stability correction factor under different driving modes.

[0042] In order to control the actual yaw rate, due to the yaw dynamic hysteresis characteristics of the vehicle, the rear axle vector distribution function needs to set the target yaw rate ψ des Delay, the delay time is a function of vehicle speed.

[0043] Optionally, in one embodiment of the present application, the rear axle torque vector control conditions are preset, including: the vehicle's gear is a forward gear; the vehicle's current speed is within a preset speed range; the vehicle's steering wheel angle is greater than a preset angle threshold, wherein the preset angle threshold is determined by the current vehicle speed; and the vehicle's steering wheel is provided with hysteresis.

[0044] For example, the rear axle torque vectoring control conditions of the embodiment of the present application may include: the vehicle is in a forward gear, the vehicle speed is within a calibratable speed range, and the steering wheel angle is greater than a threshold based on the vehicle speed and is provided with hysteresis.

[0045] In step S102 , if the preset rear axle torque vectoring control conditions are met, the vehicle's torque limit range is determined using the vehicle's control parameter boundary constraints, and the yaw rate closed-loop control torque is calculated based on the target yaw rate and the torque limit range.

[0046] It is understandable that during actual driving of a vehicle, there are various driving conditions. In some driving conditions, it is necessary to limit the torque differential to ensure smooth steering of the vehicle.

[0047] After enabling the rear axle torque vectoring control flag, the embodiment of the present application can determine the torque difference limit range based on the vehicle's control parameter boundary constraints, such as the vehicle being in a slipping driving condition, the driver's required torque, the maximum and minimum torque of the rear left motor, the maximum and minimum torque of the rear right motor, etc., and activate the yaw rate control flag to calculate the yaw rate closed-loop control torque difference.

[0048] Optionally, in one embodiment of the present application, the vehicle's control parameter boundary constraints are used to determine the vehicle's torque limit range, including: judging whether the vehicle is in a preset low-speed driving condition based on the torque control parameters; if the vehicle is in the preset low-speed driving condition, enabling the torque limit flag when the vehicle is in a preset slip scenario; reducing the initial target torque at a preset gradient until it reaches the vehicle's actual responsive value; and determining the torque limit range based on the actual responsive value, energy consumption constraints, and the vehicle's actuator capability constraints.

[0049] In the embodiment of the present application, when the slip control cannot respond to the setting of the differential torque request flag, the yaw demand can be gradually reduced.

[0050] At low speeds, vehicle performance is primarily driven by power, with yaw control as a secondary factor. Wheel slip on one side does not limit the torque of the other wheel, improving the vehicle's ability to escape. At this point, the slip control may fail to respond to the setting of the torque differential request flag.

[0051] At low speeds, when slip occurs, to ensure power consistency, priority is given to reducing the TV torque. This may result in the slip control being unable to respond to the setting of the differential torque request flag.

[0052] When driving at medium and high speeds, yaw control is the primary focus, with dynamics as a secondary factor, to improve vehicle stability. At this time, there will be no situation where the torque differential request flag cannot be set due to slip control.

[0053] During braking recovery, in order to ensure braking consistency, the TV torque is reduced first. At this time, there will be no wheel locking control and the situation where the torque differential request flag cannot be set.

[0054] When the slip control cannot respond to the torque request flag, for example, the target torque differential is 1000Nm, but the actual response is only 500Nm. Then the torque limit control will reduce the target torque differential by a gradient of 500Nm / s to a maximum torque differential of 500Nm and a minimum torque differential of -500Nm.

[0055] Energy consumption limit: When driving with small torque demand, the torque demand plus the offset is used as the upper limit of vector control. The inverse of the torque demand plus the offset is used as the lower limit of vector control, thereby limiting the amount of one wheel driving the other wheel.

[0056] Capacity limits: Minimum torque difference min ((minimum torque capacity of the rear left motor - maximum torque capacity of the rear right motor), (minimum torque capacity of the rear right motor - maximum torque capacity of the rear left motor)), maximum torque difference max ((maximum torque capacity of the rear left motor - minimum torque capacity of the rear right motor), (maximum torque capacity of the rear right motor - minimum torque capacity of the rear left motor))

[0057] The maximum and minimum differential torque limits of the output are: the maximum differential torque is the smaller of the three, and the minimum differential torque is the larger of the three.

[0058] Optionally, in one embodiment of the present application, before calculating the yaw rate closed-loop control torque in combination with the target yaw rate and the torque limit range, it also includes: identifying the steering state of the vehicle based on the torque control parameter; judging whether the vehicle meets the preset yaw rate control activation condition based on the steering state; if the preset yaw rate control activation condition is met, calculating the yaw rate closed-loop control torque in combination with the target yaw rate and the torque limit range.

[0059] The embodiments of the present application can identify the curve state based on the steering wheel angle in the torque control parameters. For example, the steering wheel angle is defined as positive on the left and negative on the right; the steering wheel angle is within a certain range and is provided with hysteresis for straight driving; the steering wheel angle is positive and the steering wheel angle change rate is greater than the positive threshold, or the steering wheel angle is negative and the steering wheel angle change rate is less than the negative threshold for entering a curve; the steering wheel angle is less than the threshold and the steering wheel angle change rate is less than the threshold for being in the middle of a curve; the steering wheel angle is negative and the steering wheel angle change rate is greater than the positive threshold, or the steering wheel angle is positive and the steering wheel angle change rate is less than the negative threshold for exiting a curve.

[0060] When the difference between the actual yaw rate and the delayed target yaw rate exceeds a threshold (a function of steering angle and vehicle speed), the rear axle vector distribution function calculates the target yaw moment through closed-loop PID control to control the actual yaw rate toward the target yaw rate. Feedforward terms are set based on vehicle speed and steering wheel angle in different driving modes. Under different cornering conditions, the proportional, integral, and differential terms are calculated by multiplying the target yaw rate, the deviation between the target yaw rate and the actual yaw rate, and then applying a correction factor based on the vehicle speed lookup table.

[0061] After the differential torque is limited, the target yaw moment M for yaw rate control is output. zψ .

[0062] In step S103, the vehicle's center of mass sideslip angle is obtained, and the center of mass sideslip angle is used to determine whether the vehicle meets the preset center of mass sideslip angle limit activation conditions, and a judgment result is obtained. The judgment result and the torque limit range are combined to obtain the vehicle's center of mass sideslip angle closed-loop control torque.

[0063] The vehicle's center of mass sideslip angle can be indirectly calculated through sensor data fusion and state estimation (usually using an observer or filter). Among them, the embodiment of the present application can use the vehicle kinematic relationship to combine the measurement values ​​of multiple sensors, such as the longitudinal acceleration, lateral acceleration and yaw angular velocity measured by the inertial measurement unit, the wheel speed measured by the wheel speed sensor, the steering wheel angle measured by the steering angle sensor, etc. to calculate the center of mass sideslip angle.

[0064] Furthermore, based on the center of mass sideslip angle, the embodiment of the present application can determine whether the vehicle needs to activate the center of mass sideslip angle control, and based on whether it is activated, determine whether it is necessary to limit the yaw moment based on the center of mass sideslip angle to obtain the center of mass sideslip angle closed-loop control torque difference.

[0065] Optionally, in one embodiment of the present application, the center of mass sideslip angle of the vehicle is obtained, and the center of mass sideslip angle is used to determine whether a preset center of mass sideslip angle limit activation condition is met to obtain a judgment result, and the center of mass sideslip angle closed-loop control torque of the vehicle is obtained by combining the judgment result and the torque limit range, including: obtaining the tire-road friction coefficient of the vehicle; matching the corresponding center of mass sideslip angle threshold based on the tire-road friction coefficient; if the absolute value of the center of mass sideslip angle is greater than the absolute value of the center of mass sideslip angle threshold, determining the center of mass sideslip angle closed-loop control torque by proportional-integral-differential control based on the difference between the center of mass sideslip angle and the center of mass sideslip angle threshold and the current vehicle speed; otherwise, determining the center of mass sideslip angle closed-loop control torque to be zero.

[0066] As a possible implementation method, in the embodiment of the present application, it can be determined whether the vehicle's center of mass side slip angle β is greater than a threshold β based on a tire-road friction coefficient μ lookup table. TH , then the yaw moment M based on the vehicle's side slip angle limit is zβ is activated.

[0067] When |β|>|β TH |When, M zβ Based on the difference (β-β TH ) PID control; otherwise, M zβ =0.

[0068] PID control is based on vehicle speed, β TH Set the feedforward term based on β TH 、(β-β TH ) table lookup multiplied by the vehicle speed table lookup to set the proportional term, integral term and differential term.

[0069] After the differential torque is limited, the target yaw moment M for yaw rate control is output. zβ .

[0070] In step S104 , the target torque difference of the vehicle is calculated by combining the yaw rate closed-loop control torque difference and the center of mass sideslip angle closed-loop control torque difference, so as to control the vehicle based on the target torque difference so that the torque vectoring control of the vehicle satisfies the preset smooth control condition.

[0071] Based on the calculation results of the above steps, the embodiment of the present application can determine the target torque difference of the vehicle to achieve smooth control of the torque difference during mode switching.

[0072] Among them, the calculation expression of the target torque is:

[0073] M z,t =ρ1(M zψ -M zβ )+M zβ

[0074] Among them, lnρ1=-ρ2(|β|-|β TH |), ensure that M zψ and M zβ Smooth transition between.

[0075] Combine Figure 2 and Figure 3 As shown, the working principle of the vehicle torque vector control method of the embodiment of the present application is described in detail using an embodiment.

[0076] like Figure 2 As shown, the vehicle involved in the embodiment of the present application can be a single-axle dual-motor structure. Based on this structure, the embodiment of the present application can realize rear axle torque vector control.

[0077] like Figure 3 As shown, based on the above structure, the embodiment of the present application may include the following steps:

[0078] Step S1: Enabling torque vectoring control. Data such as vehicle gear position, speed, steering wheel angle, and driver-requested torque are obtained to determine whether torque vectoring control can be enabled. This determination may include: the vehicle is in D gear, the speed is within a calibratable speed range, and the steering wheel angle is greater than a speed-based threshold with hysteresis.

[0079] Step S2, System Boundary Control. After activating the rear axle torque vectoring enable flag, the embodiment of the present application can combine the torque differential output from the previous cycle, the slip control unable to respond to the torque differential request flag, the driver's required torque, the maximum and minimum torques of the rear left and right motors to determine the maximum and minimum torque differential limits.

[0080] Step S3: Calculate target yaw rate. In the embodiment of the present application, the target yaw rate of the vehicle can be calculated based on the vehicle speed, steering wheel angle, steering wheel angle change rate, yaw rate, turning state, and tire-road friction coefficient.

[0081] Step S4: Target yaw rate open-loop and closed-loop control. This embodiment of the present application can determine whether yaw rate control is active and calculate the yaw rate closed-loop control torque differential based on the rear axle torque vectoring control enable flag, yaw rate, target yaw rate, vehicle speed, turn flag, turn state, steering wheel angle rate, maximum and minimum differential torque limits.

[0082] Step S5: Center of mass slip angle open-loop and closed-loop control. This embodiment of the present application can determine whether to activate center of mass slip angle control based on the rear axle torque vectoring control enable flag, center of mass slip angle, vehicle speed, tire-road friction coefficient, turning flag, maximum and minimum differential torque limits, and calculate the center of mass slip angle closed-loop control torque differential and the allowable center of mass slip angle limit.

[0083] Step S6: Mode switching to torque difference smoothing control. In this embodiment of the present application, the target torque difference can be calculated based on the yaw rate closed-loop control torque difference, the yaw rate control activation flag, the center of mass sideslip angle closed-loop control torque difference, the center of mass sideslip angle control activation flag, and the allowable center of mass sideslip angle limit.

[0084] Based on the above technical solution, the embodiment of the present application can combine scenario-based feedforward and feedback control of yaw angular velocity and center of mass side slip angle protection feedforward and feedback control, effectively consider the system boundaries, improve the vehicle driving control stability and safety, and accurately distribute torque to the left and right wheels through real-time perception of road conditions and driving intentions, and increase the maximum speed of the moose test. When the vehicle slips or loses control, the torque distribution can be quickly adjusted to help restore stability.

[0085] According to the vehicle torque vectoring control method proposed in an embodiment of the present application, whether to enable rear axle torque vectoring control can be determined based on torque control parameters. If rear axle torque vectoring control is required, the real-time calculated target yaw rate is used to confirm whether to activate the yaw rate closed-loop control torque differential, and the center of mass sideslip angle is used to determine whether to actively suppress sideslip. If active suppression is required, the target torque differential is calculated by combining the yaw rate closed-loop control torque differential and the center of mass sideslip angle closed-loop control torque differential to achieve smooth vehicle control and enhance the driver's driving experience. This solves the technical problem in related technologies where allocating driving force based on the adhesion of each wheel makes it difficult to achieve the driver's desired yaw rate, resulting in poor steering smoothness and a detrimental effect on the driver's driving experience.

[0086] Next, a vehicle torque vectoring control device according to an embodiment of the present application will be described with reference to the accompanying drawings.

[0087] Figure 4 It is a block diagram of a vehicle torque vectoring control device according to an embodiment of the present application.

[0088] like Figure 4 As shown, the vehicle torque vector control device 10 includes: an acquisition module 100 , a first calculation module 200 , a first judgment module 300 and a control module 400 .

[0089] Specifically, the acquisition module 100 is used to acquire the torque control parameters of the vehicle, determine whether the vehicle meets the preset rear axle torque vectoring control conditions based on the torque control parameters, and calculate the target yaw rate of the vehicle using the torque control parameters.

[0090] The first calculation module 200 is configured to determine a vehicle torque differential limit range by using the vehicle's control parameter boundary constraints when preset rear axle torque vectoring control conditions are met, and calculate a yaw rate closed-loop control torque differential based on the target yaw rate and the torque differential limit range.

[0091] The first judgment module 300 is used to obtain the vehicle's center of mass sideslip angle, use the center of mass sideslip angle to determine whether the vehicle meets the preset center of mass sideslip angle limit activation conditions, and obtain a judgment result. The judgment result is combined with the differential torque limit range to obtain the vehicle's center of mass sideslip angle closed-loop control differential torque.

[0092] The control module 400 is configured to calculate a target torque difference of the vehicle by combining the yaw rate closed-loop control torque difference and the center of mass sideslip angle closed-loop control torque difference, and to control the vehicle based on the target torque difference so that the torque vectoring control of the vehicle satisfies a preset smooth control condition.

[0093] Optionally, in one embodiment of the present application, the preset rear axle torque vectoring control conditions include: the vehicle is in a forward gear; the vehicle's current speed is within a preset speed range; the vehicle's steering wheel angle is greater than a preset angle threshold, where the preset angle threshold is determined by the current vehicle speed; and the vehicle's steering wheel has hysteresis.

[0094] Optionally, in one embodiment of the present application, the first calculation module 200 includes: a judgment unit, an enabling unit, an adjustment unit and a first determination unit.

[0095] The judgment unit is used to judge whether the vehicle is in a preset low-speed driving condition based on the torque control parameter.

[0096] The enabling unit is used to enable the torque limit flag when the vehicle is in a preset low-speed driving condition or in a preset slipping scenario.

[0097] The regulating unit is used to reduce the initial target torque difference at a preset gradient until it reaches an actual responsive value of the vehicle.

[0098] The first determining unit is configured to determine a differential torque limit range based on an actual responsive value, an energy consumption constraint, and an actuator capability constraint of the vehicle.

[0099] Optionally, in one embodiment of the present application, the vehicle torque vector control device 10 further includes: an identification module, a second judgment module and a second calculation module.

[0100] The identification module is used to identify the steering state of the vehicle based on the torque control parameter.

[0101] The second judgment module is used to judge whether the vehicle meets the preset yaw rate control activation condition based on the steering state.

[0102] The second calculation module is used to calculate the yaw rate closed-loop control differential torque based on the target yaw rate and the differential torque limit range when a preset yaw rate control activation condition is met.

[0103] Optionally, in one embodiment of the present application, the judgment module 103 includes: an acquisition unit, a matching unit, and a second determination unit.

[0104] The acquisition unit is used to obtain the tire-road friction coefficient of the vehicle.

[0105] The matching unit is used to match the corresponding center of mass sideslip angle threshold based on the tire-road friction coefficient.

[0106] The second determination unit is used to determine the closed-loop control torque difference of the center of mass sideslip angle by performing proportional-integral-differential control based on the difference between the center of mass sideslip angle and the center of mass sideslip angle threshold and the current vehicle speed when the absolute value of the center of mass sideslip angle is greater than the absolute value of the center of mass sideslip angle threshold; otherwise, determine that the closed-loop control torque difference of the center of mass sideslip angle is zero.

[0107] It should be noted that the aforementioned explanation of the embodiment of the vehicle torque vectoring control method is also applicable to the vehicle torque vectoring control device of this embodiment, and will not be repeated here.

[0108] According to the vehicle torque vectoring control device proposed in the embodiments of the present application, whether to enable rear axle torque vectoring control is determined based on torque control parameters. If rear axle torque vectoring control is required, the yaw rate closed-loop control torque differential is determined based on the real-time calculated target yaw rate, and whether active sideslip suppression is required is determined based on the center of mass sideslip angle. If active sideslip suppression is required, the target torque differential is calculated by combining the yaw rate closed-loop control torque differential and the center of mass sideslip angle closed-loop control torque differential to achieve smooth vehicle control and enhance the driver's driving experience. This solves the technical problem in related art where allocating driving force based on the adhesion of each wheel makes it difficult to achieve the driver's desired yaw rate, resulting in poor steering smoothness and a detrimental effect on the driver's driving experience.

[0109] Figure 5 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application. The vehicle may include:

[0110] Memory 501 , processor 502 , and computer programs stored in the memory 501 and executable on the processor 502 .

[0111] When the processor 502 executes the program, the vehicle torque vectoring control method provided in the above embodiment is implemented.

[0112] Furthermore, the vehicle further comprises:

[0113] The communication interface 503 is used for communication between the memory 501 and the processor 502 .

[0114] The memory 501 is used to store computer programs that can be run on the processor 502 .

[0115] The memory 501 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0116] If the memory 501, processor 502, and communication interface 503 are implemented independently, the communication interface 503, memory 501, and processor 502 can be connected to each other via a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5Only one bus or only one type of bus can exist, however.

[0117] Optionally, in a specific implementation, if the memory 501, the processor 502 and the communication interface 503 are integrated on a chip, the memory 501, the processor 502 and the communication interface 503 can complete the communication among each other through an internal interface.

[0118] The processor 502 can be a central processing unit (CPU) or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement one or more embodiments of the application.

[0119] The embodiment further provides a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the vehicle torque vectoring control method.

[0120] The embodiment further provides a computer program product, which includes a computer program. The computer program is executed by a processor to implement the vehicle torque vectoring control method.

[0121] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or N embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples, without contradiction.

[0122] In addition, the terms "first", "second" are only used for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "N" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0123] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing a custom logical function or process step, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may be performed in a different order than shown or discussed, including performing functions in a substantially simultaneous manner or in a reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present application pertain.

[0124] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or N wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program can be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing it in other suitable ways as necessary, and then storing it in a computer memory.

[0125] It should be understood that various parts of the present application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiment, the N steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used to implement: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0126] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0127] In addition, the functional units in the various embodiments of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into a module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0128] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application. Persons skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A vehicle torque control method, characterized in that: The following steps are involved: obtaining a torque control parameter of the vehicle, determining whether the vehicle satisfies a preset rear axle torque vectoring control condition based on the torque control parameter, and calculating a target yaw rate of the vehicle using the torque control parameter; If the preset rear axle torque vectoring control condition is met, determining a torque limit range of the vehicle using a control parameter boundary constraint of the vehicle, and calculating a yaw rate closed-loop control torque difference in combination with the target yaw rate and the torque limit range; Obtaining a center of mass sideslip angle of the vehicle, determining whether the vehicle satisfies a preset center of mass sideslip angle limit activation condition using the center of mass sideslip angle, obtaining a determination result, and combining the determination result with the differential torque limit range to obtain a closed-loop control differential torque for the center of mass sideslip angle of the vehicle; The target torque difference of the vehicle is calculated by combining the yaw rate closed-loop control torque difference and the center of mass sideslip angle closed-loop control torque difference, so as to control the vehicle based on the target torque difference so that the torque vectoring control of the vehicle satisfies a preset smooth control condition.

2. The method according to claim 1, characterized in that The preset rear axle torque vectoring control condition includes: The gear position of the vehicle is forward gear; The current speed of the vehicle is within a preset speed range; The steering wheel angle of the vehicle is greater than a preset angle threshold, wherein the preset angle threshold is determined by the current vehicle speed; The steering wheel angle condition of the vehicle is provided with hysteresis.

3. The method according to claim 1, characterized in that The determining of the vehicle's torque limit range by using the vehicle's control parameter boundary constraints includes: determining whether the vehicle is in a preset low-speed driving condition based on the torque control parameter; If the vehicle is in the preset low-speed driving condition, then enabling a differential torque limit flag when the vehicle is in a preset slip scenario; reducing the initial target torque difference at a preset gradient until it reaches an actual responsive value of the vehicle; The differential torque limit range is determined based on the actual responsive value, an energy consumption constraint, and an actuator capability constraint of the vehicle.

4. The method according to claim 1, wherein Before calculating the yaw rate closed-loop control differential torque by combining the target yaw rate and the differential torque limit range, the method further includes: identifying a steering state of the vehicle based on the torque control parameter; determining whether the vehicle satisfies a preset yaw rate control activation condition based on the steering state; If the preset yaw rate control activation condition is met, a yaw rate closed-loop control torque difference is calculated by combining the target yaw rate and the torque difference limit range.

5. The method according to claim 1, wherein The obtaining of the center of mass sideslip angle of the vehicle, determining whether a preset center of mass sideslip angle limit activation condition is satisfied using the center of mass sideslip angle, obtaining a determination result, and combining the determination result with the differential torque limit range to obtain a closed-loop control differential torque of the center of mass sideslip angle of the vehicle, includes: Obtaining a tire-road friction coefficient of the vehicle; Matching a corresponding center of mass sideslip angle threshold based on the tire-road friction coefficient; If the absolute value of the center of mass sideslip angle is greater than the absolute value of the center of mass sideslip angle threshold, the center of mass sideslip angle closed-loop control torque difference is determined by proportional-integral-differential control based on the difference between the center of mass sideslip angle and the center of mass sideslip angle threshold and the current vehicle speed; otherwise, the center of mass sideslip angle closed-loop control torque difference is determined to be zero.

6. A vehicle torque vector control device, characterized in that: include: an acquisition module, configured to acquire a torque control parameter of a vehicle, determine whether the vehicle satisfies a preset rear axle torque vectoring control condition based on the torque control parameter, and calculate a target yaw rate of the vehicle using the torque control parameter; a calculation module, configured to determine a torque differential limit range of the vehicle by using a control parameter boundary constraint of the vehicle when the preset rear axle torque vectoring control condition is satisfied, and calculate a yaw rate closed-loop control torque differential by combining the target yaw rate and the torque differential limit range; a judgment module, configured to obtain a center of mass sideslip angle of the vehicle, determine whether the vehicle satisfies a preset center of mass sideslip angle limit activation condition using the center of mass sideslip angle, obtain a judgment result, and combine the judgment result with the differential torque limit range to obtain a closed-loop control differential torque for the center of mass sideslip angle of the vehicle; A control module is configured to calculate a target torque difference of the vehicle by combining the yaw rate closed-loop control torque difference and the center of mass sideslip angle closed-loop control torque difference, so as to control the vehicle based on the target torque difference so that the torque vectoring control of the vehicle satisfies a preset smooth control condition.

7. The device according to claim 6, characterized in that The calculation module includes: a judging unit, configured to judge whether the vehicle is in a preset low-speed driving condition based on the torque control parameter; an enabling unit, configured to enable a differential torque limiting flag when the vehicle is in the preset low-speed driving condition or when the vehicle is in a preset slipping scenario; an adjusting unit, configured to reduce an initial target torque difference at a preset gradient until it reaches an actual responsive value of the vehicle; A determination unit is configured to determine the torque differential limit range based on the actual responsive value, an energy consumption constraint, and an actuator capability constraint of the vehicle.

8. A vehicle, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the vehicle torque vectoring control method according to any one of claims 1 to 5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the vehicle torque vectoring control method according to any one of claims 1 to 5.

10. A computer program product comprising a computer program, characterized in that When the computer program is executed, it is used to implement the vehicle torque vectoring control method according to any one of claims 1 to 5.

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