CN119502713A

CN119502713A - Traction control method and device for electric vehicle

Info

Publication number: CN119502713A
Application number: CN202311061705.XA
Authority: CN
Inventors: 朱燕青; 张雯雯; 奉柳; M·Y·D·S·穆拉
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2023-08-22
Filing date: 2023-08-22
Publication date: 2025-02-25

Abstract

The present invention discloses a traction control method for an electric vehicle. The method comprises: obtaining the whole vehicle acceleration of the electric vehicle and the driving wheel acceleration of the electric vehicle; determining whether the electric vehicle is in a slipping state based at least in part on the difference between the whole vehicle acceleration and the driving wheel acceleration; when it is determined that the electric vehicle is in a slipping state, adjusting the motor input torque of the electric vehicle based at least in part on the difference between the whole vehicle acceleration and the driving wheel acceleration.

Description

Traction control method and apparatus for electric vehicle

Technical Field

The present disclosure relates generally to electric vehicles, and more particularly, to traction control methods and apparatus for electric vehicles.

Background

"Slip" refers to a phenomenon in which a vehicle runs with uncontrolled slip due to insufficient ground friction or loss of a stable form, which directly causes safety problems. An anti-lock braking system (ABS) is a device capable of automatically controlling the magnitude of braking force of a brake when a vehicle is braked, so that wheels are not locked and are in a rolling and sliding state, and the adhesion between the wheels and the ground is ensured to be at a maximum value. The ABS system typically determines whether the vehicle is in a "slip" state by the difference in speed between the drive wheel and the brake wheel or the difference in acceleration between the vehicle and the drive wheel, and once the vehicle is in a "slip" state, the ABS system will generate a torque down signal that acts on the drive system to cause the vehicle to be in a controlled state.

The existing ABS system is mainly used for gasoline powered vehicles, while current electric vehicles have almost no ABS system installed. Moreover, the current ABS system requires a wheel speed sensor or an inertial sensor, which is costly.

Disclosure of Invention

It is desirable to provide a traction control method and apparatus for an electric vehicle that can prevent the occurrence of a "slip" risk by adjusting torque without the aid of a wheel speed sensor and an inertial sensor at high cost, and can be applied to different road or driving scenarios, thereby improving the safety factor of the vehicle while the electric vehicle is driving.

According to one aspect of the present invention, a traction control method for an electric vehicle is provided. The method includes obtaining a vehicle acceleration of the electric vehicle and a drive wheel acceleration of the electric vehicle, determining whether the electric vehicle is in a slip state based at least in part on a difference of the vehicle acceleration and the drive wheel acceleration, and adjusting a motor input torque of the electric vehicle based at least in part on the difference of the vehicle acceleration and the drive wheel acceleration when the electric vehicle is determined to be in a slip state.

According to yet another aspect of the present invention, a traction control system for an electric vehicle is provided. The system includes a memory, a processor coupled to the memory, the processor configured to cause one or more units to perform the method according to any of the various embodiments of the invention.

According to yet another aspect of the present invention, a traction control system for an electric vehicle is provided. The system includes a motor, a drive wheel, a controller coupled to the motor, the controller configured to cause one or more units to perform the method according to any of the various embodiments of the invention.

According to yet another aspect of the invention, a computer-readable medium is provided, storing a computer program comprising instructions that, when executed by a processor, cause one or more units to perform a method according to any of the various embodiments of the invention.

According to a further aspect of the invention there is provided an electric vehicle comprising one or more units performing the method according to any of the various embodiments of the invention.

Drawings

Various embodiments of the claimed subject matter will now be described, by way of example, with reference to the accompanying drawings. The use of the same reference symbols in different drawings indicates identical or similar items.

Fig. 1A illustrates a traction control system for an electric vehicle according to an embodiment of the present invention.

Fig. 1B illustrates a controller in a traction control system for an electric vehicle according to an embodiment of the present invention.

Fig. 2 shows a data flow diagram for traction control of an electric vehicle according to an embodiment of the invention.

Fig. 3 shows a flowchart of a traction control method for an electric vehicle according to an embodiment of the present invention.

Fig. 4 shows a block diagram of an apparatus that may be used for a traction control method of an electric vehicle according to an embodiment of the present invention.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention may be practiced without one or more of the specific details, or with alternative methods, components, etc. In some instances, well known structures, operations are not shown or described in detail to avoid unnecessarily obscuring the invention.

It should be understood that the term "electric vehicle" or other similar terms as used herein include, for example, passenger vehicles (including sport utility vehicles, buses, trucks, etc.), various commercial vehicles, etc., and include electric automobiles, electric tricycles, electric bikes such as electric motorcycles or electric bicycles, and the like.

"Slip" refers to a phenomenon in which a vehicle runs with uncontrolled slip due to insufficient ground friction or loss of a stable form, which directly causes safety problems. The ABS system typically determines whether the vehicle is in a "slip" state by the difference in speed between the drive wheel and the brake wheel or the difference in acceleration between the vehicle and the drive wheel, and once the vehicle is in a "slip" state, the ABS system will generate a torque down signal that acts on the drive system to cause the vehicle to be in a controlled state. While current electric vehicles have almost no ABS system installed, and ABS systems require wheel speed sensors or inertial sensors, which are costly. Therefore, a new solution for electric vehicles is needed to achieve traction control with accuracy and robustness.

Fig. 1A shows a traction control system for an electric vehicle according to an embodiment of the present invention, including a motor 1, a controller 2, a driving wheel 3, a driven wheel 4, and a sensor 5. The motor 1 is connected to the driving wheel 3 to drive it to rotate, and the controller 2 is connected to at least the motor 1, the driven wheel 4 and the sensor 5 to obtain data captured by the sensor 5 and to adjust the input torque of the motor 1 according to the data captured by the sensor 5.

Fig. 1B shows a controller 2 in a traction control system for an electric vehicle according to an embodiment of the present invention, including at least one or more of a calculation unit 21, a storage unit 22, a judgment unit 23, and a control unit 24, which are electrically connected to each other.

In one embodiment, the calculation unit 21 calculates the whole vehicle acceleration and the driving wheel acceleration of the electric vehicle, and the respective parameters required for the calculation are stored in the storage unit 22. The determination unit 23 determines whether the electric vehicle is in a slip state based on the obtained difference between the acceleration of the entire vehicle and the acceleration of the drive wheels. When it is determined that the electric vehicle is in a slip state, the trigger control unit 24 adjusts the motor input torque of the vehicle based on the difference between the acceleration of the entire vehicle and the acceleration of the drive wheels.

In one embodiment, the calculation unit 21 obtains the entire vehicle acceleration a ₀ of the electric vehicle based on the formula (1):

Where T is the drive wheel output torque, R is the drive wheel radius, m is the sum of the masses of the electric vehicle and the driver, and f is the resistance experienced by the electric vehicle.

In one embodiment, the drive wheel output torque may be calculated from the power of the motor and the rotational speed of the motor, e.g., t=p/ω. In another embodiment, where the torque of the motor has a predetermined relationship with the current and motor parameters, the drive wheel output torque T may be calculated from sampled data of the phase current and/or line current of the motor in combination with the motor parameters. In other embodiments, any suitable method of calculating motor output torque in the art may be used.

In an embodiment the mass of the driver may be determined by one of nominally determining the mass of the driver, e.g. 75kg, according to different vehicle types, by means of a gravity sensor via a calculation unit 21 or by means of a calculation unit 21 based on the driving wheel output torque.

In one embodiment, f is the sum of one or more of air resistance, ramp resistance, and rolling resistance. The air resistance, the ramp resistance, and the rolling resistance may be obtained based on formulas (2) - (4):

wherein C _d is the air friction coefficient, A is the cross-sectional area of the electric vehicle, v is the travel speed of the electric vehicle, g is the gravitational acceleration, μ is the sliding friction coefficient, Is the climbing angle of the electric vehicle, and wherein C _d, g, μmay be determined by any suitable means in the art.

In one embodiment, v may be obtained via any suitable sensor within the electric vehicle, for example, a rotor position sensor within the electric machine 1.

In one embodiment of the present invention, in one embodiment,Can be determined by any suitable means in the art. For example, the gradient of the road surface on which the current vehicle is located is calculated from the difference between the acceleration of the entire vehicle and the longitudinal acceleration and the gravitational acceleration. For another example, the gradient estimation is based on a Kalman filtering algorithm. In one embodiment of the present invention, in one embodiment,May be calculated in real time as the vehicle travels via the calculation unit 21.

In one embodiment, the vehicle acceleration a ₀ may be well estimated when the vehicle is traveling on a level road. However, when the vehicle is ascending, f calculated according to formulas (2) - (4) may increase, and thus a ₀ calculated according to formula (1) may be smaller. In such a case, the determination unit 23 that determines whether the electric vehicle is in a slip state based on the obtained difference between the vehicle acceleration a ₀ and the driving wheel acceleration a ₁ may make a false determination (for example, a ₀<a₁), resulting in a false trigger that may be caused to the torque adjustment by the control unit 24. While when the vehicle is on a downhill slope, f calculated according to formulas (2) - (4) may decrease, and thus a ₀ calculated according to formula (1) may be larger. In such a case, a severe slip condition of the electric vehicle may still be detected, without the problem of false triggering of torque adjustment. Therefore, when the electric vehicle is in the climbing state, the calculating unit 21 may compensate the calculated acceleration a ₀ of the whole vehicle by a buffer value to reduce the mass m and/or the climbing angle determinedAn error of a ₀ calculated relative to the actual value caused by the error of (a).

In one embodiment, the buffer value used to compensate for the calculated vehicle acceleration a ₀ may be determined by any suitable means in the art. For example, the buffer value may be statistically determined from the demonstration data. For another example, the buffer value may be calculated and determined based on one or more of a climbing angle of the electric vehicle, a sum of weights of the electric vehicle and the driver, and a cross-sectional area of the electric vehicle.

In one embodiment, the calculation unit 21 calculates the obtained driving wheel acceleration a ₁ of the electric vehicle based on the traveling speed of the electric vehicle. For example, the travel speed of the electric vehicle may be determined by the sensor 5 within the motor 1. The drive wheel acceleration may be calculated based on the travel speed of the vehicle in any suitable manner in the art. For example, a differential algorithm is employed to calculate the driving wheel acceleration based on the traveling speed of the vehicle. For another example, a Kalman filter algorithm is used to calculate the drive wheel acceleration based on the speed of travel of the vehicle.

In one embodiment, the determination unit 23 determines that the electric vehicle is in a slip state based on a comparison of the obtained difference between the acceleration of the entire vehicle and the acceleration of the drive wheels with a predetermined threshold value. In one embodiment, the predetermined threshold is stored in the storage unit 22. In general, the predetermined threshold may be zero, that is, when the driving wheel acceleration is greater than the whole vehicle acceleration, the judgment unit 23 determines that the electric vehicle is in a slip state. In some cases, for example, when the vehicle is in a hill climbing process, the calculated acceleration of the entire vehicle may be small, so that the predetermined threshold value may be set to a value smaller than zero, whereby false triggering of torque adjustment may be avoided. In one embodiment, the predetermined threshold may be determined based on one or more of a hill climbing angle of the electric vehicle, a sum of weights of the electric vehicle and the driver, and a cross-sectional area of the electric vehicle. In one embodiment, the predetermined threshold may be determined by the calculation unit 21. In other cases, even if the vehicle is in a climbing process, as described above, the calculation unit 21 may compensate the calculated vehicle acceleration a ₀ by a buffer value, and the determination unit 23 may determine that the electric vehicle is in a slip state based on the compensated vehicle acceleration.

In one embodiment, when it is determined that the electric vehicle is in a slip state, control unit 24 is triggered to generate a compensation torque value based on the difference between the vehicle acceleration and the drive wheel acceleration to adjust the motor input torque of the vehicle. When the vehicle is in a slip state, the compensation torque value needs to be used for reducing the motor input torque so as to reduce the driving wheel output torque, and therefore the grip force is recovered to enable the vehicle to exit from a runaway state.

In one embodiment, control unit 24 may be any suitable controller in the art. For example, the control unit 24 may be a proportional-integral controller.

In one embodiment, the drive wheel may be a rear wheel of an electric vehicle. The electric vehicle may be an electric automobile, an electric tricycle, an electric two-wheeled vehicle such as an electric motorcycle or an electric bicycle. When the number of driving wheels 3 of the electric vehicle exceeds 1, the relevant parameter may be calculated from the sensor 5 in the motor 1 of only one of the driving wheels 3. Alternatively, the relevant parameters may be calculated from the sensors 5 within the motors 1 of the plurality of driving wheels 3.

As shown in fig. 2, the entire vehicle acceleration a ₀ and the driving wheel acceleration a ₁ of the electric vehicle are obtained. In one embodiment, the vehicle acceleration a ₀ and the drive wheel acceleration a ₁ may be obtained by the calculation unit 21 described with reference to fig. 1B.

In one embodiment, the vehicle acceleration a ₀ may be calculated according to equations (1) - (4) described above. In one embodiment, the driving wheel acceleration a ₁ may be calculated based on the travel speed of the electric vehicle as described above.

In one embodiment, when the electric vehicle is in a climbing state, the acceleration a ₀ of the whole electric vehicle can be compensated by a buffer value b. In one embodiment, the buffer value b for compensating the calculated vehicle acceleration a ₀ may be determined by any suitable means in the art. For example, the buffer value may be statistically determined based on empirical data (including experimental data of various road surfaces such as slopes, experimental data of various road conditions). For another example, the buffer value may be calculated and determined based on one or more of a climbing angle of the electric vehicle, a sum of weights of the electric vehicle and the driver, and a cross-sectional area of the electric vehicle. In one embodiment, the buffer value B may be determined by the calculation unit 21 described with reference to fig. 1B.

As further shown in fig. 2, a difference Δa=a ₀-a₁ between the entire vehicle acceleration a ₀ and the driving wheel acceleration a ₁ is obtained, and it is determined whether the electric vehicle is in a slip state based on Δa. In one embodiment, whether the electric vehicle is in a slip state may be determined by the determination unit 23 described with reference to fig. 1B.

In one embodiment, it may be determined that the electric vehicle is in a slip state based on a comparison of Δa and a predetermined threshold. In one embodiment, the predetermined threshold is zero and the electric vehicle is determined to be in a slip state when Δa <0. In another embodiment, the predetermined threshold thr is a value less than zero when the vehicle is in a hill climbing process, and the electric vehicle is determined to be in a slip state when Δa < thr. In one embodiment, the predetermined threshold may be computationally determined based on one or more of a hill climbing angle of the electric vehicle, a sum of weights of the electric vehicle and the driver, and a cross-sectional area of the electric vehicle. In one embodiment, the predetermined threshold may be determined by the computing unit described with reference to fig. 1B.

In an alternative embodiment, when the vehicle is in a hill climbing state, a difference Δa=a ₀+b-a₁ of the compensated entire vehicle acceleration a ₀ +b and the driving wheel acceleration a ₁ is obtained, and it is determined whether the electric vehicle is in a slip state based on Δa. In one embodiment, the predetermined threshold is zero and the electric vehicle is determined to be in a slip state when Δa < 0. Although the examples given in the above embodiments are Δa smaller than a predetermined threshold, it is also possible in other equivalent embodiments to determine that the electric vehicle is in a slip state based on Δa (e.g. Δa=a ₁-(a₀ +b)) having different definitions and this Δa being larger than a predetermined threshold, i.e. when the difference (e.g. Δa=a ₁-(a₀ +b)) of the driving wheel acceleration from the vehicle acceleration exceeds a predetermined threshold (e.g. a value of 0 or larger than zero), depending on different calculation rules and symbols.

As further shown in fig. 2, when it is determined that the electric vehicle is in a slip state, the motor input torque T _re of the electric vehicle is adjusted based on the difference Δa of the entire vehicle acceleration a ₀ and the driving wheel acceleration a ₁. In one embodiment, adjusting the motor input torque of the electric vehicle may be performed by the control unit 24 described with reference to fig. 1B.

In one embodiment, a compensation torque value T _co can be generated based on the difference Δa between the vehicle acceleration a ₀ and the drive wheel acceleration a ₁ to adjust the motor input torque of the electric vehicle. In one embodiment, the compensation torque value may be generated by a proportional-integral controller whose input is the difference Δa and whose output is the compensation torque value T _co. In one embodiment, when the input Δa of the proportional-integral controller is negative, the compensation torque value T _co of its output is positive.

In another embodiment, it will be readily appreciated by those skilled in the art that the control unit 24 may be other suitable controller in other equivalent embodiments, and the compensation torque value T _co output may be positive or negative when the input Δa of the control unit 24 is negative, depending on different calculation rules and symbols.

In one embodiment, when the output compensation torque value T _co is positive, the obtained compensation torque value T _co may be subtracted from the given torque T _re of the electric vehicle to make an adjustment, and the adjusted torque value (T _re-T_co) is taken as the final motor input torque T. In other embodiments, when the output compensation torque value T _co is negative, an adjustment may be made with the given torque T _re of the electric vehicle plus the obtained compensation torque value T _co, and the adjusted torque value (T _re+T_co) is taken as the final motor input torque T. The adjustment of the given torque with the compensation torque value may be done in any manner applicable in the art, by way of example only and not limitation. Wherein the given torque T _re may be a required torque determined based on an operation of the driver. When the electric vehicle is a two-wheeled vehicle, the given torque T _re may be a required torque determined based on a steering opening degree generated by a driver acting on a steering of the two-wheeled vehicle. The motor input torque T refers to the torque T input to the motor by the controller. Specifically, a voltage signal representing the opening degree of the steering handle generated by the operation of the steering handle by the driver is fed back to the controller, and the controller obtains the given torque T _re based on the voltage signal.

In step S310, a device (such as an electric vehicle, a processor in an electric vehicle, one or more units in an electric vehicle) provided with the controller 2 for traction control obtains the entire vehicle acceleration of the electric vehicle and the driving wheel acceleration of the electric vehicle.

In one embodiment, the entire vehicle acceleration of the electric vehicle may be obtained based on equation (1). The parameters in equation (1) can be obtained with reference to the foregoing description.

In one embodiment, when the electric vehicle is in a climbing state, the calculated acceleration of the whole vehicle can be compensated by a buffer value. In one embodiment, the buffer value used for compensation may be determined by any suitable means in the art. For example, the buffer value may be statistically determined from the demonstration data. For another example, the buffer value may be calculated and determined based on one or more of a climbing angle of the electric vehicle, a sum of weights of the electric vehicle and the driver, and a cross-sectional area of the electric vehicle.

In one embodiment, the acceleration of the drive wheels of the electric vehicle is obtained based on the travel speed of the electric vehicle determined by a rotor position sensor within the electric machine.

In step S320, the apparatus determines whether the electric vehicle is in a slip state based at least in part on a difference between the vehicle acceleration and the drive wheel acceleration.

In one embodiment, the electric vehicle is determined to be in a slip state when a difference between the vehicle acceleration and the drive wheel acceleration is less than a predetermined threshold. In one embodiment, the predetermined threshold may be zero, i.e., when the drive wheel acceleration is greater than the vehicle acceleration, it is determined that the electric vehicle is in a slip state. In another embodiment, the predetermined threshold may be set to a value less than zero to avoid false triggering of torque adjustments during vehicle uphill. In one embodiment, the predetermined threshold may be determined based on one or more of a hill climbing angle of the electric vehicle, a sum of weights of the electric vehicle and the driver, and a cross-sectional area of the electric vehicle.

In step S330, when it is determined that the electric vehicle is in a slip state, the apparatus adjusts a motor input torque of the electric vehicle based at least in part on the difference between the vehicle acceleration and the drive wheel acceleration.

In one embodiment, a compensation torque value is generated based on the difference to adjust a motor input torque of the electric vehicle. In one embodiment, the compensation torque value is generated by a proportional integral controller.

In one embodiment, the adjustment may be made using a given torque of the electric vehicle minus the obtained compensation torque value, and the adjusted torque value is taken as the final motor input torque.

In one embodiment, the drive wheels of the electric vehicle may be rear wheels of the electric vehicle. The electric vehicle can be an electric automobile, an electric tricycle, an electric motorcycle or an electric bicycle. When the number of driving wheels of the electric vehicle exceeds 1, the relevant parameter may be calculated from only a sensor in the motor of one of the driving wheels. Alternatively, the relevant parameters may be calculated from sensors within the motors of the plurality of drive wheels.

Fig. 4 shows a block diagram of an apparatus that may be used for a traction control method of an electric vehicle according to an embodiment of the present invention. In one embodiment of the invention, the apparatus may include a control unit or auxiliary system of the vehicle, such as an Electronic Control Unit (ECU), an Electronic Management Unit (EMU), a traction control system, an anti-lock system, or the like. In other embodiments, the apparatus may comprise an electric vehicle.

The example apparatus includes a processor 404 coupled to the internal communication bus 402, the processor 404 configured to execute instructions in a memory 406 to implement the traction control method for an electric vehicle described in detail above. Examples of processor 404 may include a Central Processing Unit (CPU), a microcontroller, and so forth. Memory 406 suitable for tangibly embodying computer program instructions and data includes various forms of memory, e.g., EPROM, EEPROM, and flash memory devices, among others. The device may also include an input interface 408 and an output interface 410. The input interface 408 is used to receive input signals and data, for example, data from various sensors. The output interface 410 is used to send output signals and data, such as various commands or signaling for traction control of an electric vehicle.

The computer program may include instructions executable by a computer for causing the processor 404 of the device to perform the traction control method for an electric vehicle of the present invention. The program may be recorded on any data storage medium including a memory. For example, the program may be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. The process/method steps described in the present invention may be performed by a programmable processor executing program instructions to perform methods, steps, operations by operating on input data and generating output.

According to yet another aspect of the present invention, a traction control system for an electric vehicle is provided. The system includes a motor, a drive wheel, a controller coupled to the motor, the controller configured to cause one or more units to perform the method according to any of the various embodiments of the invention. Wherein the controller and the motor may be integrated or separately provided. The electric vehicle may be an electric two-wheeled vehicle, the motor may be a wheel hub motor, and the controller may be an inverter that may be integrated with the wheel hub motor.

In addition to what is described herein, various modifications may be made to the disclosed embodiments and implementations of the invention without departing from the scope of the disclosed embodiments and implementations. The specification and examples herein are, accordingly, to be regarded in an illustrative rather than a restrictive sense. The scope of the invention should be measured solely by reference to the claims.

Claims

1. A traction control method for an electric vehicle, comprising:

Acquiring the whole vehicle acceleration of the electric vehicle and the driving wheel acceleration of the electric vehicle;

determining whether the electric vehicle is in a slip state based at least in part on a difference between the vehicle acceleration and the drive wheel acceleration;

When it is determined that the electric vehicle is in a slip state, a motor input torque of the electric vehicle is adjusted based at least in part on the difference in the vehicle acceleration and the drive wheel acceleration.

2. The method of claim 1, wherein the vehicle acceleration of the electric vehicle is obtained based on:

Wherein a ₀ is the acceleration of the whole vehicle, T is the output torque of driving wheels, R is the radius of the driving wheels, m is the sum of the weights of the electric vehicle and a driver, and f is the resistance suffered by the electric vehicle.

3. The method of claim 2, wherein the driver's quality is determined by one of:

Nominally determining the mass of the driver according to different vehicle models;

determining the mass of the driver by means of a gravity sensor, or

The mass of the driver is determined based on a drive wheel output torque.

4. The method of claim 2, wherein the resistance experienced by the electric vehicle is a sum of one or more of air resistance, ramp resistance, and rolling resistance.

5. The method of claim 4, wherein the air resistance, ramp resistance, and rolling resistance are obtained based on the following formula:

Wherein C _d is an air friction coefficient, A is a cross-sectional area of the electric vehicle, v is a traveling speed of the electric vehicle, g is a gravitational acceleration, μ is a sliding friction coefficient, Is the climbing angle of the electric vehicle.

6. The method of claim 1, further comprising:

when the electric vehicle is in a climbing state, the obtained acceleration of the whole vehicle of the electric vehicle is compensated by a buffer value.

7. The method of claim 6, wherein the buffer value is determined based on one or more of a grade angle of the electric vehicle, a sum of weights of the electric vehicle and a driver, and a cross-sectional area of the electric vehicle.

8. The method of claim 1, wherein the drive wheel acceleration of the electric vehicle is obtained based on a travel speed of the electric vehicle, the travel speed of the electric vehicle being determined by a position sensor within a motor.

9. The method of claim 1, wherein determining whether the electric vehicle is in a slip state based at least in part on the difference in the vehicle acceleration and the drive wheel acceleration comprises:

And determining that the electric vehicle is in a slip state when the difference between the acceleration of the whole vehicle and the acceleration of the driving wheels is smaller than a preset threshold value.

10. The method of claim 1, wherein adjusting the motor input torque of the electric vehicle based at least in part on the difference of the vehicle acceleration and the drive wheel acceleration comprises:

a compensation torque value is generated based on the difference to adjust the motor input torque of the electric vehicle.

11. The method of claim 10, wherein the compensation torque value is generated by a proportional-integral controller.

12. The method of claim 10, wherein generating the compensation torque value based on the difference to adjust the motor input torque of the electric vehicle comprises:

subtracting the compensation torque value from a required torque determined based on a driver operation of the electric vehicle as the motor input torque of the electric vehicle.

13. The method of claim 12, wherein the requested torque determined based on a driver operation of the electric vehicle is determined based on a handle opening of the electric vehicle.

14. The method of claim 1, wherein the drive wheel is a rear wheel of the electric vehicle.

15. The method of claim 1, wherein the electric vehicle comprises an electric two-wheeled vehicle.

16. A traction control system for an electric vehicle, comprising:

A memory;

a processor coupled with the memory, the processor configured to cause one or more units to perform the method of any of claims 1-15.

17. A traction control system for an electric vehicle, comprising:

A motor;

A driving wheel;

A controller coupled with the motor, the controller configured to cause one or more units to perform the method of any of claims 1-15.

18. A computer-readable medium storing a computer program comprising instructions that, when executed by a processor, cause one or more units to perform the method of any of claims 1-15.

19. An electric vehicle comprising one or more units performing the method of any of claims 1-15.