Electric four-wheel drive vehicle TCS control method, device, vehicle and storage medium

Abstract

The present invention relates to the technical field of vehicles, and specifically discloses a TCS control method, device, vehicle and storage medium for an electric four-wheel drive vehicle. The method comprises: when TCS is turned on, performing TCS control on each drive system respectively; during TCS control, when the actual slip rate of a first wheel and a second wheel is greater than their respective target slip rates, determining a first traction force based on a first target slip rate and a maximum braking force of a first brake; determining a second traction force based on a second target slip rate and a maximum braking force of a second brake; the first target traction force output by a driving motor is equal to a smaller value between the first traction force and the second traction force, and determining target braking forces output by two brakes based on the target traction forces and target slip rates of the two wheels respectively, thereby ensuring the stability of the vehicle, and realizing maximum utilization of the ground adhesion coefficient, thereby ensuring the power of the vehicle.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a TCS control method, device, vehicle and storage medium for an electric four-wheel drive vehicle. Background Art

[0002] The traction control system (TCS) is mainly used to control the slippage of the driving wheels when the vehicle starts or accelerates on ice, snow, sand and other roads. TCS actively controls the vehicle's traction and rationally utilizes the adhesion between the wheels and the ground to provide the vehicle with dynamics and stability on low-adhesion roads.

[0003] For electric four-wheel drive dual-motor models, the front and rear axles are powered by separate motors respectively. The motor torque rises too quickly. When the brake TCS function is triggered, the hydraulic rising rate cannot follow quickly due to wheel slippage, resulting in the inability to fully utilize the ground adhesion coefficient, affecting the vehicle's acceleration ability and stability. Summary of the invention

[0004] The purpose of the present invention is to provide a TCS control method, device, vehicle and storage medium for an electric four-wheel drive vehicle, so as to solve the problem in the prior art that when the braking TCS function of an electric four-wheel drive dual-motor vehicle is triggered, the hydraulic rising rate cannot follow quickly due to wheel slippage, resulting in the inability to fully utilize the ground adhesion coefficient, affecting the vehicle's acceleration ability and stability.

[0005] The present invention provides a TCS control method for an electric four-wheel drive vehicle, wherein the vehicle comprises two drive systems, the two drive systems are arranged at intervals along the front-rear direction of the vehicle, the drive systems comprise a drive shaft, a drive motor drivingly connected to the drive shaft, a first wheel and a second wheel arranged at both ends of the drive shaft, a first brake for providing braking force to the first wheel, and a second brake for providing braking force to the second wheel, and the TCS control method for the electric four-wheel drive vehicle comprises:

[0006] Acquiring operating parameters of the vehicle, the operating parameters including a first rotation speed of each first wheel, a second rotation speed of each second wheel, an acceleration of the vehicle, a throttle opening of an accelerator, a pedal opening of a brake pedal, and a driving speed of the vehicle;

[0007] determining a first actual slip ratio of the first wheel based on a driving speed of the vehicle and a first rotation speed of the first wheel;

[0008] determining a second actual slip ratio of the second wheel based on a driving speed of the vehicle and a second rotation speed of the second wheel;

[0009] Make sure TCS is turned on;

[0010] Perform TCS control on each drive system separately;

[0011] TCS controls include:

[0012] determining a first target slip ratio of the first wheel based on a driving speed of the vehicle and a first rotation speed of the first wheel;

[0013] determining a second target slip ratio of the second wheel based on a driving speed of the vehicle and a second rotation speed of the second wheel;

[0014] comparing the first actual slip ratio and the first target slip ratio, and the second actual slip ratio and the second target slip ratio;

[0015] If the first actual slip ratio is greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio;

[0016] determining a first traction force based on a first target slip ratio and a maximum braking force of a first brake;

[0017] determining a second traction force based on a second target slip ratio and a maximum braking force of a second brake;

[0018] The driving motor outputs a first target traction force, where the first target traction force is equal to a smaller value between the first traction force and the second traction force;

[0019] determining a first target braking force output by the first brake based on the first target traction force and the first target slip ratio;

[0020] determining a second target braking force output by the second brake based on the first target traction force and the second target slip ratio;

[0021] The first brake outputs a first target braking force;

[0022] The second brake outputs a second target braking force.

[0023] As a preferred technical solution of the TCS control method for electric four-wheel drive vehicles, if the first actual slip ratio is not greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio;

[0024] determining a second traction force based on a second target slip ratio and a maximum braking force of a second brake;

[0025] The driving motor outputs a first target traction force, and the first target traction force is equal to the second traction force;

[0026] determining a first target braking force output by the first brake based on the first target traction force and the first target slip ratio;

[0027] The first brake outputs a first target braking force;

[0028] The second brake outputs a second target braking force, and the second target braking force output by the second brake is equal to the maximum braking force of the second brake.

[0029] As a preferred technical solution of the TCS control method for electric four-wheel drive vehicles, if the first actual slip ratio is greater than the first target slip ratio, and the second actual slip ratio is not greater than the second target slip ratio;

[0030] determining a first traction force based on a first target slip ratio and a maximum braking force of a first brake;

[0031] The driving motor outputs a first target traction force, and the first target traction force is equal to the first traction force;

[0032] determining a second target braking force output by the second brake based on the first target traction force and the second target slip ratio;

[0033] The first brake outputs a first target braking force, and the first target braking force output by the first brake is equal to the maximum braking force of the first brake;

[0034] The second brake outputs a second target braking force.

[0035] As a preferred technical solution of the TCS control method for electric four-wheel drive vehicles, if the first actual slip ratio is not greater than the first target slip ratio, and the second actual slip ratio is not greater than the second target slip ratio;

[0036] determining a first traction force based on a first target slip ratio and a maximum braking force of a first brake;

[0037] determining a second traction force based on a second target slip ratio and a maximum braking force of a second brake;

[0038] The driving motor outputs a first target traction force, where the first target traction force is equal to a smaller value between the first traction force and the second traction force;

[0039] determining a first target braking force output by the first brake based on the first target traction force and the first target slip ratio;

[0040] determining a second target braking force output by the second brake based on the first target traction force and the second target slip ratio;

[0041] The first brake outputs a first target braking force;

[0042] The second brake outputs a second target braking force.

[0043] As a preferred technical solution of the TCS control method for an electric four-wheel drive vehicle, the TCS control method for an electric four-wheel drive vehicle further includes between determining a second actual slip ratio of the second wheel based on the vehicle's driving speed and a second rotation speed of the second wheel and determining that the TCS is turned on:

[0044] Make sure that there is no fault in the TCS.

[0045] The present invention also provides a TCS control device for an electric four-wheel drive vehicle, comprising:

[0046] a parameter acquisition module, used to acquire operating parameters of the vehicle, the operating parameters including a first rotation speed of each first wheel, a second rotation speed of each second wheel, an acceleration of the vehicle, a throttle opening of an accelerator, a pedal opening of a brake pedal, and a driving speed of the vehicle;

[0047] a first actual slip ratio determination module, configured to determine a first actual slip ratio of the first wheel based on a driving speed of the vehicle and a first rotation speed of the first wheel;

[0048] a second actual slip ratio determination module, configured to determine a second actual slip ratio of the second wheel based on a driving speed of the vehicle and a second rotation speed of the second wheel;

[0049] A TCS on determination module, used to determine TCS on;

[0050] A TCS control module, used for performing TCS control on the drive system, the TCS control module comprising a first target slip ratio determination unit, a second target slip ratio determination unit, a comparison unit, a first traction force determination unit, a second traction force determination unit, a first execution unit, a first target braking force determination unit, a second target braking force determination unit and a first target braking force execution unit;

[0051] The first target slip ratio determination unit is used to determine a first target slip ratio of the first wheel based on a driving speed of the vehicle and a first rotational speed of the first wheel; the second target slip ratio determination unit is used to determine a second target slip ratio of the second wheel based on the driving speed of the vehicle and a second rotational speed of the second wheel; the comparison unit is used to compare the first actual slip ratio and the first target slip ratio, and the second actual slip ratio and the second target slip ratio; when the first actual slip ratio is greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio, the first traction force determination unit is used to determine the first traction force based on the first target slip ratio and the maximum braking force of the first brake; the second traction force determination unit is used to determine the first traction force based on the first target slip ratio and the maximum braking force of the first brake; The second traction force is determined based on the second target slip ratio and the maximum braking force of the second brake; the first execution unit is used to enable the drive motor to output the first target traction force, and the first target traction force is equal to the smaller value between the first traction force and the second traction force; the first target braking force determination unit is used to determine the first target braking force output by the first brake based on the first target traction force and the first target slip ratio; the second target braking force determination unit is used to determine the second target braking force output by the second brake based on the first target traction force and the second target slip ratio; the first target braking force execution unit is used to enable the first brake to output the first target braking force; the second target braking force execution unit is used to enable the second brake to output the second target braking force.

[0052] As a preferred technical solution for the TCS control device of an electric four-wheel drive vehicle, when the first actual slip ratio is not greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio, the second traction force determination unit is used to determine the second traction force based on the second target slip ratio and the maximum braking force of the second brake; the first execution unit is used to enable the drive motor to output the first target traction force, and the first target traction force is equal to the second traction force; the first target braking force determination unit is used to determine the first target braking force output by the first brake based on the first target traction force and the first target slip ratio; the first target braking force execution unit is used to enable the first brake to output the first target braking force; the second target braking force execution unit is used to enable the second brake to output the second target braking force, and the second target braking force output by the second brake is equal to the maximum braking force of the second brake.

[0053] As a preferred technical solution for the TCS control device of an electric four-wheel drive vehicle, when the first actual slip ratio is less than the first target slip ratio and the second actual slip ratio is not greater than the second target slip ratio, the first traction force determination unit is used to determine the first traction force based on the first target slip ratio and the maximum braking force of the first brake; the first execution unit is used to enable the drive motor to output the first target traction force, and the first target traction force is equal to the first traction force; the second target braking force determination unit is used to determine the second target braking force output by the second brake based on the first target traction force and the second target slip ratio; the first target braking force execution unit is used to enable the first brake to output the first target braking force, and the first target braking force output by the first brake is equal to the maximum braking force of the first brake; the second target braking force execution unit is used to enable the second brake to output the second target braking force.

[0054] The present invention also provides a vehicle, comprising a TCS and two drive systems, the two drive systems are arranged at intervals along the front-rear direction of the vehicle, the drive system comprises a drive shaft, a drive motor drivingly connected to the drive shaft, a first wheel and a second wheel arranged at both ends of the drive shaft, a first brake for providing braking force to the first wheel, and a second brake for providing braking force to the second wheel; the vehicle also comprises:

[0055] Controller;

[0056] A first rotation speed sensor is used to detect the rotation speed of the first wheel and send the detected first wheel rotation speed to the controller;

[0057] a second rotation speed sensor, used for detecting the rotation speed of the second wheel, and sending the detected rotation speed of the second wheel to the controller;

[0058] An acceleration sensor, used for detecting the acceleration of the vehicle and sending the detected acceleration to the controller;

[0059] A throttle opening sensor is used to detect the throttle opening and send the detected throttle opening to the controller;

[0060] A position sensor, used for detecting a position of a brake pedal and sending the detected position of the brake pedal to a controller;

[0061] A speed sensor, used for detecting the speed of the vehicle and sending the detected speed of the vehicle to the controller;

[0062] A memory for storing one or more programs;

[0063] When one or more programs are executed by the controller, the controller controls the vehicle to implement the TCS control method for an electric four-wheel drive vehicle as in any of the above-mentioned solutions.

[0064] The present invention provides a storage medium having a computer program stored thereon, characterized in that when the program is executed by a controller, the vehicle implements the TCS control method of an electric four-wheel drive vehicle as described in any one of the above-mentioned solutions.

[0065] The beneficial effects of the present invention are:

[0066] The present invention provides a TCS control method, device, vehicle and storage medium for an electric four-wheel drive vehicle. The TCS control method for an electric four-wheel drive vehicle performs TCS control on each drive system after TCS is turned on, and can control only one of the drive systems or both drive systems at the same time. During TCS control, when the first actual slip rate of the first wheel is greater than its first target slip rate, and the second actual slip rate of the second wheel is greater than its second target slip rate, the first traction force is determined based on the first target slip rate and the maximum braking force of the first brake; the second traction force is determined based on the second target slip rate and the maximum braking force of the second brake; the first target traction force output by the drive motor is equal to the smaller value between the first traction force and the second traction force, the first target braking force output by the first brake is determined based on the first target traction force and the first target slip rate, and the second target braking force output by the second brake is determined based on the second target traction force and the second target slip rate, so that the actual slip rates of the first wheel and the second wheel can be reduced to within their respective target slip rates, thereby ensuring the stability of the vehicle, and at the same time, the ground adhesion coefficient can be utilized to the maximum extent to ensure the power of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 Flow chart of the TCS control method for an electric four-wheel drive vehicle in an embodiment of the present invention;

[0068] Figure 2 The process of TCS control in the TCS control method of the electric four-wheel drive vehicle in the embodiment of the present invention is as follows: Figure 1 ;

[0069] Figure 3 The process of TCS control in the TCS control method of the electric four-wheel drive vehicle in the embodiment of the present invention is as follows: Figure 2 ;

[0070] Figure 4 The process of TCS control in the TCS control method of the electric four-wheel drive vehicle in the embodiment of the present invention is as follows: Figure 3 ;

[0071] Figure 5 The process of TCS control in the TCS control method of the electric four-wheel drive vehicle in the embodiment of the present invention is as follows: Figure 4 ;

[0072] Figure 6This is a schematic diagram of the structure of a TCS control device for an electric four-wheel drive vehicle in an embodiment of the present invention;

[0073] Figure 7 Schematic diagram of the structure of a vehicle in an embodiment of the present invention.

[0074] In the figure:

[0075] 110. Parameter acquisition module; 111. First actual slip ratio determination module; 112. Second actual slip ratio determination module; 113. TCS start determination module; 114. TCS control module;

[0076] 120. TCS; 121. driving motor; 122. first brake; 123. second brake; 124. controller; 125. first speed sensor; 126. second speed sensor; 127. acceleration sensor; 128. throttle opening sensor; 129. position sensor; 130. speed sensor; 131. memory. DETAILED DESCRIPTION

[0077] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0078] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions, and the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0079] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0080] Embodiments of the present invention are described in detail below, and examples of the embodiments 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 only used to explain the present invention, and cannot be understood as limiting the present invention.

[0081] The traction control system (TCS) is mainly used to control the slippage of the driving wheels when the vehicle starts or accelerates on ice, snow, sand and other roads. TCS actively controls the vehicle's traction and rationally utilizes the adhesion between the wheels and the ground to provide the vehicle with dynamics and stability on low-adhesion roads.

[0082] For electric four-wheel drive dual-motor models, the front and rear axles are powered by separate motors respectively. The motor torque rises too quickly. When the brake TCS function is triggered, the hydraulic rising rate cannot follow quickly due to wheel slippage, resulting in the inability to fully utilize the ground adhesion coefficient, affecting the vehicle's acceleration ability and stability.

[0083] This embodiment provides a TCS control method for an electric four-wheel drive vehicle. The TCS control method for an electric four-wheel drive vehicle can be executed by a TCS control device for an electric four-wheel drive vehicle. The TCS control device for an electric four-wheel drive vehicle can be implemented by software and / or hardware and integrated in a vehicle.

[0084] The TCS control method for electric four-wheel drive vehicles is applicable to vehicles with dual drive systems, where the two drive systems are spaced apart along the front-rear direction of the vehicle, and the drive system includes a drive shaft, a drive motor connected to the drive shaft, a first wheel and a second wheel arranged at both ends of the drive shaft, a first brake for providing braking force to the first wheel, and a second brake for providing braking force to the second wheel. The drive motor is used to provide traction to the drive shaft, and the brake is used to provide braking force to the corresponding wheel.

[0085] Specifically, Figure 1 As shown, the TCS control method of the electric four-wheel drive vehicle includes the following steps:

[0086] S1000: Obtaining vehicle operating parameters.

[0087] The operating parameters include a first rotation speed of each first wheel, a second rotation speed of each second wheel, an acceleration of the vehicle, a throttle opening of an accelerator, a pedal opening of a brake pedal, and a driving speed of the vehicle. The rotation speed of the first wheel can be detected by a first rotation speed sensor, the rotation speed of the second wheel can be detected by a second sensor, the acceleration of the vehicle can be detected by an acceleration sensor, the throttle opening can be detected by a throttle opening sensor, the position of the brake pedal can be detected by a position sensor installed on the brake pedal, and the driving speed of the vehicle can be detected by a speed sensor.

[0088] S2000: Determine a first actual slip ratio of the first wheel based on a driving speed of the vehicle and a first rotation speed of the first wheel.

[0089] S3000: Determine a second actual slip ratio of the second wheel based on the vehicle's driving speed and a second rotation speed of the second wheel.

[0090] The first actual slip ratio is calculated by the difference between the vehicle's running speed and the first rotational speed of the first wheel, and the second actual slip ratio is calculated by the difference between the vehicle's running speed and the second speed of the second wheel.

[0091] S4000: Confirm that TCS is turned on.

[0092] The method for determining whether TCS is turned on is a prior art. For example, when the control button of TCS is on and when the first actual slip ratio and the second actual slip ratio exceed a threshold value, the TCS function is turned on and intervenes to control each drive motor and each brake.

[0093] S5000: Perform TCS control on each drive system separately.

[0094] The TCS control method for an electric four-wheel drive vehicle provided in this embodiment can realize that TCS can control only one of the drive systems or both drive systems at the same time by controlling the two drive systems separately.

[0095] Among them, Figure 2-Figure 5 As shown, TCS control includes the following steps:

[0096] S5001: Determine a first target slip ratio of the first wheel based on the driving speed of the vehicle and a first rotation speed of the first wheel.

[0097] S5002: Determine a second target slip ratio of the second wheel based on the vehicle's driving speed and a second rotation speed of the second wheel.

[0098] The controller pre-stores a first relationship chart of the driving speed, the rotation speed of the wheel and the target slip ratio. The corresponding first target slip ratio can be queried from the first relationship chart according to the driving speed and the first rotation speed. The corresponding second target slip ratio can be queried from the first relationship chart according to the driving speed and the second rotation speed. The first relationship chart of the driving speed, the rotation speed of the wheel and the target slip ratio can be obtained based on a large number of previous experiments.

[0099] S5003: Compare the first actual slip ratio and the first target slip ratio, and compare the second actual slip ratio and the second target slip ratio.

[0100] If the first actual slip ratio is greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio, step S5004 is executed.

[0101] S5004: Determine a first traction force based on the first target slip ratio and the maximum braking force of the first brake.

[0102] S5005: Determine a second traction force based on the second target slip ratio and the maximum braking force of the second brake.

[0103] The controller pre-stores a second relationship chart of target slip ratio, braking force and traction force. According to the first target slip ratio and the maximum braking force of the first brake, the corresponding first traction force can be queried from the second relationship chart. According to the second target slip ratio and the maximum braking force of the second brake, the corresponding second traction force can be queried from the second relationship chart. Among them, the second relationship chart of target slip ratio, braking force and traction force can be obtained based on a large number of previous experiments.

[0104] S5006: The driving motor outputs a first target traction force, where the first target traction force is equal to a smaller value between the first traction force and the second traction force.

[0105] It can be understood that when the first actual slip ratio is greater than the first target slip ratio, it means that the slip ratio of the first wheel is too large, affecting the stability of the vehicle. Similarly, when the second actual slip ratio is greater than the second target slip ratio, it means that the slip ratio of the second wheel is too large, affecting the stability of the vehicle. When the first actual slip ratio is not greater than the first target slip ratio, it means that the slip ratio of the first wheel is within the permitted range and will not affect the stability of the vehicle. Similarly, when the second actual slip ratio is not greater than the second target slip ratio, it means that the slip ratio of the second wheel is within the permitted range and will not affect the stability of the vehicle.

[0106] When the first actual slip ratio of the first wheel is greater than the first target slip ratio, the actual slip ratio of the first wheel needs to be reduced to within the first target slip ratio through the control of TSC, and when the second actual slip ratio of the second wheel is greater than the second target slip ratio, the actual slip ratio of the second wheel needs to be reduced to within the second target slip ratio through the control of TSC to ensure the stability of the vehicle. Therefore, by determining the first traction force corresponding to the first target slip ratio through step S5004, determining the second traction force corresponding to the second target slip ratio through step S5005, and then selecting the smaller value of the first traction force and the second traction force as the first target traction force output by the driving motor through step S5006, it can ensure that the actual slip ratio of the first wheel and the actual slip ratio of the second wheel are adjusted to within the range of their respective target slip ratios, ensure the stability of the vehicle operation, and at the same time ensure that the vehicle can make the maximum use of the ground adhesion coefficient and ensure the dynamic performance of the vehicle operation.

[0107] S5007: Determine a first target braking force output by the first brake based on the first target traction force and the first target slip ratio.

[0108] S5008: Determine a second target braking force output by the second brake based on the first target traction force and the second target slip ratio.

[0109] The first target braking force corresponding to the first target traction force and the first target slip ratio can be queried from the second relationship chart. The second target braking force corresponding to the second target traction force and the second target slip ratio can be queried from the second relationship chart.

[0110] Through steps S5004 to S5008, the slip rates of the first wheel and the second wheel can be adjusted to their respective target slip rate ranges at the same time to ensure the stability of the vehicle, and can also ensure that the first wheel and the second wheel remain within the target slip rate range to ensure the power of the vehicle.

[0111] S5009: The first brake outputs a first target braking force.

[0112] S5010: The second brake outputs a second target braking force.

[0113] like Figure 3 As shown, in step S5003, if the first actual slip ratio is not greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio, S5011 is executed.

[0114] S5011: Determine a second traction force based on a second target slip ratio and a maximum braking force of a second brake.

[0115] S5012: The driving motor outputs a first target traction force, and the first target traction force is equal to the second traction force.

[0116] When the first actual slip rate is not greater than the first target slip rate, and the second actual slip rate is greater than the second target slip rate, it means that only the stability of the second wheel is poor. Therefore, it is necessary to reduce the traction output by the drive motor through TCS to reduce the actual slip rate of the second wheel to within the second target slip rate to ensure the stability of the vehicle.

[0117] S5013: Determine a first target braking force output by the first brake based on the first target traction force and the first target slip ratio.

[0118] The corresponding first target braking force can be queried from the second relationship chart according to the first target traction force and the first target slip ratio.

[0119] S5014: the first brake outputs a first target braking force;

[0120] S5015: The second brake outputs a second target braking force.

[0121] The second target braking force output by the second brake is equal to the maximum braking force of the second brake.

[0122] Through steps S5011 to S5015, the slip rate of the second wheel can be adjusted to its target slip rate range at the same time to ensure the stability of the vehicle, and the first wheel and the second wheel can also be maintained within the target slip rate to ensure the dynamics of the vehicle and maximize the use of the ground adhesion coefficient.

[0123] like Figure 4 As shown, in step S5003, if the first actual slip ratio is greater than the first target slip ratio, and the second actual slip ratio is not greater than the second target slip ratio; then S5016 is executed.

[0124] S5016: Determine a first traction force based on the first target slip ratio and the maximum braking force of the first brake.

[0125] S5017: The driving motor outputs a first target traction force, and the first target traction force is equal to the first traction force.

[0126] When the first actual slip rate is greater than the first target slip rate, and the second actual slip rate is not greater than the second target slip rate, it means that only the stability of the first wheel is poor. Therefore, it is necessary to reduce the traction output by the drive motor through TCS to reduce the actual slip rate of the first wheel to within the first target slip rate to ensure the stability of the vehicle.

[0127] S5018: Determine a second target braking force output by the second brake based on the first target traction force and the second target slip ratio.

[0128] The corresponding second target braking force can be queried from the second relationship chart according to the first target traction force and the second target slip ratio.

[0129] S5019: the first brake outputs a first target braking force, wherein the first target braking force output by the first brake is equal to a maximum braking force of the first brake;

[0130] S5020: The second brake outputs a second target braking force.

[0131] Through steps S5016 to S5020, the slip rate of the first wheel can be adjusted to its target slip rate range at the same time to ensure the stability of the vehicle, and the first wheel and the second wheel can also be maintained within the target slip rate to ensure the dynamics of the vehicle and maximize the use of the ground adhesion coefficient.

[0132] like Figure 5 As shown, in step S5003, if the first actual slip ratio is not greater than the first target slip ratio, and the second actual slip ratio is not greater than the second target slip ratio; then S5021 is executed.

[0133] S5021: Determine a first traction force based on a first target slip ratio and a maximum braking force of a first brake.

[0134] S5022: Determine a second traction force based on the second target slip ratio and the maximum braking force of the second brake.

[0135] The corresponding first traction force can be queried from the second relationship chart according to the first target slip ratio and the maximum braking force of the first brake. The corresponding second traction force can be queried from the second relationship chart according to the second target slip ratio and the maximum braking force of the second brake.

[0136] S5023: The driving motor outputs a first target traction force, where the first target traction force is equal to a smaller value between the first traction force and the second traction force.

[0137] When the first actual slip ratio is not greater than the first target slip ratio, and the second actual slip ratio is not greater than the second target slip ratio, it means that the two wheels will not affect the stability of the vehicle, and the ground adhesion coefficient is not used to the maximum extent. Therefore, the first actual slip ratio of the first wheel and the second actual slip ratio of the second wheel can be increased accordingly through TCS to ensure the dynamic performance of the vehicle.

[0138] S5024: Determine a first target braking force output by the first brake based on the first target traction force and the first target slip ratio.

[0139] S5025: Determine a second target braking force output by the second brake based on the first target traction force and the second target slip ratio.

[0140] The first target braking force corresponding to the first target traction force and the first target slip ratio can be queried from the second relationship chart. The second target braking force corresponding to the second target traction force and the second target slip ratio can be queried from the second relationship chart.

[0141] S5026: The first brake outputs a first target braking force.

[0142] S5027: The second brake outputs the second target braking force.

[0143] Through steps S5021 to S5027, the slip rates of the first wheel and the second wheel can be improved within the range of their respective target slip rates, and the ground adhesion coefficient can be utilized to the maximum extent while ensuring the stability of the vehicle.

[0144] Optionally, the TCS control method for an electric four-wheel drive vehicle further includes step S3001 between step S3000 and step S4000.

[0145] S3001: Determine whether there is a fault in TCS.

[0146] The controller can interact with the vehicle controller to determine whether the TCS is faulty. Common faults of TCS include line faults. When TCS is fault-free, S4000 is executed. If TCS is faulty, an alarm is issued.

[0147] Embodiment 2

[0148] This embodiment provides a TCS control device for an electric four-wheel drive vehicle, which is used to implement the above-mentioned TCS control method for an electric four-wheel drive vehicle. Figure 6 As shown, the TCS control device of the electric four-wheel drive vehicle includes:

[0149] The parameter acquisition module 110 is used to acquire the operating parameters of the vehicle, which include the first rotation speed of each first wheel, the second rotation speed of each second wheel, the acceleration of the vehicle, the throttle opening of the accelerator, the pedal opening of the brake pedal and the driving speed of the vehicle.

[0150] The first actual slip ratio determination module 111 is configured to determine a first actual slip ratio of the first wheel based on a driving speed of the vehicle and a first rotation speed of the first wheel.

[0151] The second actual slip ratio determination module 112 is configured to determine a second actual slip ratio of the second wheel based on the vehicle's driving speed and a second rotation speed of the second wheel.

[0152] The TCS on determination module 113 is configured to determine whether the TCS is on.

[0153] The TCS control module 114 is used to perform TCS control on the drive system. The TCS control module 114 includes a first target slip ratio determination unit, a second target slip ratio determination unit, a comparison unit, a first traction force determination unit, a second traction force determination unit, a first execution unit, a first target braking force determination unit, a second target braking force determination unit and a first target braking force execution unit.

[0154] The first target slip ratio determination unit is used to determine a first target slip ratio of the first wheel based on a driving speed of the vehicle and a first rotational speed of the first wheel; the second target slip ratio determination unit is used to determine a second target slip ratio of the second wheel based on the driving speed of the vehicle and a second rotational speed of the second wheel; the comparison unit is used to compare the first actual slip ratio and the first target slip ratio, and the second actual slip ratio and the second target slip ratio; when the first actual slip ratio is greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio, the first traction force determination unit is used to determine the first traction force based on the first target slip ratio and the maximum braking force of the first brake; the second traction force determination unit is used to determine the first traction force based on the first target slip ratio and the maximum braking force of the first brake; The second traction force is determined based on the second target slip ratio and the maximum braking force of the second brake; the first execution unit is used to enable the drive motor to output the first target traction force, and the first target traction force is equal to the smaller value between the first traction force and the second traction force; the first target braking force determination unit is used to determine the first target braking force output by the first brake based on the first target traction force and the first target slip ratio; the second target braking force determination unit is used to determine the second target braking force output by the second brake based on the first target traction force and the second target slip ratio; the first target braking force execution unit is used to enable the first brake to output the first target braking force; the second target braking force execution unit is used to enable the second brake to output the second target braking force.

[0155] Optionally, when the first actual slip ratio is not greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio, the second traction force determination unit is used to determine the second traction force based on the second target slip ratio and the maximum braking force of the second brake; the first execution unit is used to enable the drive motor to output a first target traction force, and the first target traction force is equal to the second traction force; the first target braking force determination unit is used to determine the first target braking force output by the first brake based on the first target traction force and the first target slip ratio; the first target braking force execution unit is used to enable the first brake to output the first target braking force; the second target braking force execution unit is used to enable the second brake to output a second target braking force, and the second target braking force output by the second brake is equal to the maximum braking force of the second brake.

[0156] Optionally, when the first actual slip ratio is less than the first target slip ratio, and the second actual slip ratio is not greater than the second target slip ratio, the first traction force determination unit is used to determine the first traction force based on the first target slip ratio and the maximum braking force of the first brake; the first execution unit is used to enable the drive motor to output a first target traction force, and the first target traction force is equal to the first traction force; the second target braking force determination unit is used to determine the second target braking force output by the second brake based on the first target traction force and the second target slip ratio; the first target braking force execution unit is used to enable the first brake to output the first target braking force, and the first target braking force output by the first brake is equal to the maximum braking force of the first brake; the second target braking force execution unit is used to enable the second brake to output the second target braking force.

[0157] The TCS control device for an electric four-wheel drive vehicle provided in the second embodiment of the present invention can be used to execute the TCS control method for an electric four-wheel drive vehicle provided in the above embodiment, and has corresponding functions and beneficial effects.

[0158] Embodiment 3

[0159] like Figure 7 As shown, this embodiment provides a vehicle, which includes a TCS120 and two drive systems, which are arranged at intervals along the front-rear direction of the vehicle, and the drive system includes a drive shaft, a drive motor 121 connected to the drive shaft, a first wheel and a second wheel arranged at both ends of the drive shaft, a first brake 122 for providing braking force to the first wheel, and a second brake 123 for providing braking force to the second wheel. The vehicle also includes a controller 124, a first speed sensor 125, a second speed sensor 126, an acceleration sensor 127, a throttle opening sensor 128, a position sensor 129, a speed sensor 130 and a memory 131. Among them, the controller 124, the first speed sensor 125, the second speed sensor 126, the acceleration sensor 127, the throttle opening sensor 128, the position sensor 129, the speed sensor 130 and the memory 131, the TCS120, the first brake 122, the second brake 123 and the drive motor 121 can be connected through a bus.

[0160] The first speed sensor 125 is used to detect the speed of the first wheel, and send the detected speed of the first wheel to the controller 124; the second speed sensor 126 is used to detect the speed of the second wheel, and send the detected speed of the second wheel to the controller 124; the acceleration sensor 127 is used to detect the acceleration of the vehicle, and send the detected acceleration to the controller 124; the throttle opening sensor 128 is used to detect the opening of the throttle, and send the detected opening of the throttle to the controller 124; the position sensor 129 is used to detect the position of the brake pedal, and send the detected position of the brake pedal to the controller 124; the speed sensor 130 is used to detect the speed of the vehicle, and send the detected speed of the vehicle to the controller 124.

[0161] The memory 131 is a computer-readable storage medium that can be used to store software programs, computer executable programs and modules, such as program instructions / modules corresponding to the TCS control method for electric four-wheel drive vehicles in the embodiment of the present invention. The controller 124 executes various functional applications and data processing of the vehicle by running the software programs, instructions and modules stored in the memory 131, that is, the TCS control method for electric four-wheel drive vehicles in the above embodiment is implemented.

[0162] The memory 131 mainly includes a program storage area and a data storage area, wherein the program storage area can store an operating system and at least one application required for a function; the data storage area can store data created according to the use of the terminal, etc. In addition, the memory 131 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some examples, the memory 131 may further include a memory remotely arranged relative to the controller 124, and these remote memories can be connected to the vehicle via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0163] The vehicle provided in the third embodiment of the present invention and the TCS control method for electric four-wheel drive vehicles provided in the above embodiment belong to the same inventive concept. The technical details not described in detail in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as executing the TCS control method for electric four-wheel drive vehicles.

[0164] Embodiment 4

[0165] Embodiment 4 of the present invention further provides a storage medium on which a computer program is stored. When the program is executed by a controller, the TCS control method for an electric four-wheel drive vehicle as described in the above embodiment of the present invention is implemented.

[0166] Of course, the storage medium containing computer executable instructions provided in the embodiment of the present invention is not limited to the operations in the TCS control method of the electric four-wheel drive vehicle as described above, but can also execute the relevant operations in the TCS control device of the electric four-wheel drive vehicle provided in the embodiment of the present invention, and has corresponding functions and beneficial effects.

[0167] Through the above description of the implementation mode, the technicians in the relevant field can clearly understand that the present invention can be implemented by means of software and necessary general hardware, and of course it can also be implemented by hardware, but in many cases the former is a better implementation mode. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory (FLASH), hard disk or optical disk, etc., including a number of instructions for a computer device (which can be a robot, a personal computer, a server, or a network device, etc.) to execute the electric four-wheel drive vehicle TCS control method described in each embodiment of the present invention.

[0168] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A TCS control method for an electric four-wheel drive vehicle, wherein the vehicle comprises two drive systems, the two drive systems are arranged at intervals along the front-rear direction of the vehicle, the drive systems comprise a drive shaft, a drive motor drivingly connected to the drive shaft, a first wheel and a second wheel arranged at both ends of the drive shaft, a first brake for providing braking force to the first wheel, and a second brake for providing braking force to the second wheel, characterized in that: The TCS control method for electric four-wheel drive vehicles includes: Acquiring operating parameters of the vehicle, the operating parameters including a first rotation speed of each of the first wheels, a second rotation speed of each of the second wheels, an acceleration of the vehicle, a throttle opening of an accelerator, a pedal opening of a brake pedal, and a driving speed of the vehicle; determining a first actual slip ratio of the first wheel based on a travel speed of the vehicle and a first rotation speed of the first wheel; determining a second actual slip ratio of the second wheel based on a travel speed of the vehicle and a second rotation speed of the second wheel; Make sure TCS is turned on; Performing TCS control on each of the drive systems respectively; The TCS control includes: determining a first target slip ratio of the first wheel based on a travel speed of the vehicle and a first rotation speed of the first wheel; determining a second target slip ratio of the second wheel based on a travel speed of the vehicle and a second rotation speed of the second wheel; comparing the first actual slip ratio and the first target slip ratio, and the second actual slip ratio and the second target slip ratio; If the first actual slip ratio is greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio; determining a first traction force based on the first target slip ratio and a maximum braking force of the first brake; determining a second traction force based on the second target slip ratio and the maximum braking force of the second brake; The driving motor outputs a first target traction force, where the first target traction force is equal to a smaller value between the first traction force and the second traction force; determining a first target braking force output by the first brake based on the first target traction force and the first target slip ratio; determining a second target braking force output by the second brake based on the first target traction force and the second target slip ratio; The first brake outputs a first target braking force; The second brake outputs a second target braking force; If the first actual slip ratio is not greater than the first target slip ratio, and the second actual slip ratio is not greater than the second target slip ratio; determining a first traction force based on the first target slip ratio and a maximum braking force of the first brake; determining a second traction force based on the second target slip ratio and the maximum braking force of the second brake; The driving motor outputs a first target traction force, where the first target traction force is equal to a smaller value between the first traction force and the second traction force; determining a first target braking force output by the first brake based on the first target traction force and the first target slip ratio; determining a second target braking force output by the second brake based on the first target traction force and the second target slip ratio; The first brake outputs a first target braking force; The second brake outputs a second target braking force; When the first actual slip rate is not greater than the first target slip rate, and the second actual slip rate is not greater than the second target slip rate, it means that the two wheels will not affect the stability of the vehicle at this time, and the ground adhesion coefficient is not utilized to the maximum extent. The slip rates of the first wheel and the second wheel can be increased within the range of their respective target slip rates. Under the premise of ensuring the stability of the vehicle, the ground adhesion coefficient can be utilized to the maximum extent.

2. The TCS control method for electric four-wheel drive vehicles according to claim 1, characterized in that: If the first actual slip ratio is not greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio; determining a second traction force based on the second target slip ratio and the maximum braking force of the second brake; The driving motor outputs a first target traction force, and the first target traction force is equal to the second traction force; determining a first target braking force output by the first brake based on the first target traction force and the first target slip ratio; The first brake outputs a first target braking force; The second brake outputs a second target braking force, and the second target braking force output by the second brake is equal to the maximum braking force of the second brake.

3. The TCS control method for electric four-wheel drive vehicle according to claim 2, characterized in that: If the first actual slip ratio is greater than the first target slip ratio, and the second actual slip ratio is not greater than the second target slip ratio; determining a first traction force based on the first target slip ratio and a maximum braking force of the first brake; The driving motor outputs a first target traction force, and the first target traction force is equal to the first traction force; determining a second target braking force output by the second brake based on the first target traction force and the second target slip ratio; The first brake outputs a first target braking force, and the first target braking force output by the first brake is equal to the maximum braking force of the first brake; The second brake outputs a second target braking force.

4. The TCS control method for electric four-wheel drive vehicles according to claim 1, characterized in that: The TCS control method for an electric four-wheel drive vehicle further includes between determining a second actual slip ratio of the second wheel based on a driving speed of the vehicle and a second rotation speed of the second wheel and determining that the TCS is turned on: Make sure that there is no fault in the TCS.

5. A TCS control device for an electric four-wheel drive vehicle, characterized in that: The method for controlling the TCS of an electric four-wheel drive vehicle according to any one of claims 1 to 4 comprises: a parameter acquisition module, used to acquire operating parameters of the vehicle, the operating parameters including a first rotation speed of each first wheel, a second rotation speed of each second wheel, an acceleration of the vehicle, a throttle opening of an accelerator, a pedal opening of a brake pedal, and a driving speed of the vehicle; a first actual slip ratio determination module, configured to determine a first actual slip ratio of the first wheel based on a driving speed of the vehicle and a first rotation speed of the first wheel; a second actual slip ratio determination module, configured to determine a second actual slip ratio of the second wheel based on a driving speed of the vehicle and a second rotation speed of the second wheel; A TCS on determination module, used to determine TCS on; A TCS control module, used for performing TCS control on the drive system, the TCS control module comprising a first target slip ratio determination unit, a second target slip ratio determination unit, a comparison unit, a first traction force determination unit, a second traction force determination unit, a first execution unit, a first target braking force determination unit, a second target braking force determination unit and a first target braking force execution unit; The first target slip ratio determination unit is used to determine a first target slip ratio of the first wheel based on a driving speed of the vehicle and a first rotation speed of the first wheel; the second target slip ratio determination unit is used to determine a second target slip ratio of the second wheel based on a driving speed of the vehicle and a second rotation speed of the second wheel; the comparison unit is used to compare the first actual slip ratio and the first target slip ratio, and the second actual slip ratio and the second target slip ratio; when the first actual slip ratio is greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio, the first traction force determination unit is used to determine a first traction force based on the first target slip ratio and a maximum braking force of a first brake; the second traction force determination unit is used to determine a first traction force based on The second traction force is determined based on the second target slip ratio and the maximum braking force of the second brake; the first execution unit is used to enable the drive motor to output a first target traction force, and the first target traction force is equal to the smaller value between the first traction force and the second traction force; the first target braking force determination unit is used to determine the first target braking force output by the first brake based on the first target traction force and the first target slip ratio; the second target braking force determination unit is used to determine the second target braking force output by the second brake based on the first target traction force and the second target slip ratio; the first target braking force execution unit is used to enable the first brake to output the first target braking force; and the second target braking force execution unit is used to enable the second brake to output the second target braking force.

6. The TCS control device for an electric four-wheel drive vehicle according to claim 5, characterized in that: When the first actual slip ratio is not greater than the first target slip ratio, and the second actual slip ratio is greater than the second target slip ratio, the second traction force determination unit is used to determine a second traction force based on the second target slip ratio and the maximum braking force of the second brake; The first execution unit is used to make the drive motor output a first target traction force, and the first target traction force is equal to the second traction force; the first target braking force determination unit is used to determine a first target braking force output by the first brake based on the first target traction force and the first target slip ratio; The first target braking force execution unit is used to make the first brake output a first target braking force; The second target braking force execution unit is used to enable the second brake to output a second target braking force, and the second target braking force output by the second brake is equal to the maximum braking force of the second brake.

7. The TCS control device for an electric four-wheel drive vehicle according to claim 5, characterized in that: When the first actual slip ratio is less than the first target slip ratio, and the second actual slip ratio is not greater than the second target slip ratio, the first traction force determination unit is used to determine a first traction force based on the first target slip ratio and a maximum braking force of the first brake; The first execution unit is used to make the driving motor output a first target traction force, and the first target traction force is equal to the first traction force; The second target braking force determination unit is used for determining a second target braking force output by the second brake based on the first target traction force and the second target slip ratio; The first target braking force execution unit is used to make the first brake output a first target braking force, and the first target braking force output by the first brake is equal to the maximum braking force of the first brake; the second target braking force execution unit is used to make the second brake output a second target braking force.

8. A vehicle, comprising a TCS and two drive systems, the two drive systems being arranged at intervals along the front-rear direction of the vehicle, the drive systems comprising a drive shaft, a drive motor drivingly connected to the drive shaft, a first wheel and a second wheel arranged at both ends of the drive shaft, a first brake for providing braking force to the first wheel, and a second brake for providing braking force to the second wheel; characterized in that: The vehicle further comprises: Controller; a first rotation speed sensor, used for detecting the rotation speed of the first wheel, and sending the detected rotation speed of the first wheel to the controller; a second rotation speed sensor, used for detecting the rotation speed of the second wheel, and sending the detected rotation speed of the second wheel to the controller; An acceleration sensor, used for detecting the acceleration of the vehicle and sending the detected acceleration to the controller; A throttle opening sensor, used for detecting the throttle opening and sending the detected throttle opening to the controller; a position sensor, used for detecting the position of the brake pedal and sending the detected position of the brake pedal to the controller; A speed sensor, used for detecting the speed of the vehicle and sending the detected speed of the vehicle to the controller; A memory for storing one or more programs; When the one or more programs are executed by the controller, the controller controls the vehicle to implement the TCS control method for an electric four-wheel drive vehicle according to any one of claims 1 to 4.

9. A storage medium having a computer program stored thereon, characterized in that: When the program is executed by the controller, the vehicle implements the TCS control method for an electric four-wheel drive vehicle as described in any one of claims 1-4.

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