WO2024259599A1 - Motor control method and apparatus for electric vehicle, and storage medium - Google Patents

Abstract

A motor control method for an electric vehicle, comprising: acquiring vehicle operation information of an electric vehicle; determining a basic motor torque of a motor of the electric vehicle on the basis of the vehicle operation information; determining a zero-crossing compensation torque of the motor on the basis of the basic motor torque; determining a corrected motor torque of the motor on the basis of the basic motor torque and the zero-crossing compensation torque; and, on the basis of the corrected motor torque, controlling an output torque of the motor so as to perform zero crossing. Thus, the corrected motor torque is used to implement zero crossing of the motor, so that backlash impact caused by switching of positive and negative torques of the motor is reduced or even eliminated, that is, zero-crossing impact is reduced or even eliminated. The present application relates to a motor control apparatus for an electric vehicle, and an electric vehicle.

Description

Motor control method, device and storage medium for electric vehicle Technical Field

The present application relates to the field of power drive control, and in particular to a motor control method, device and storage medium for an electric vehicle.

Background Art

In the field of power drive control of electric vehicles, the motor and the wheel are connected through a gear (or spline) mechanism to form a drive system to transmit power. Motor drive and motor braking are achieved by controlling the output torque of the motor. When the motor is in positive and negative torque conversion (or zero crossing), the meshing direction of the meshing gear (or spline) of the drive system changes, and the force direction of the gear (or spline) connected to the wheel changes, which will cause tooth hitting and damage to the transmission mechanism such as gears or splines. In addition, it will also produce shocks and noises that users can clearly perceive, affecting driving comfort. Especially for low-speed conditions, the tooth gap impact (or zero crossing impact) caused by the positive and negative torque switching of the motor will be more obviously perceived by the user.

In the related art, in order to solve the above problems, a fixed torque or a slower torque change rate is usually used for zero-crossing control to reduce the zero-crossing impact, which is generally called zero-crossing platform torque control. However, this method still has the problem of increasing zero-crossing impact when the braking force, ramp, vehicle resistance or road resistance changes.

Summary of the invention

The embodiments of the present application provide a motor control method, device and storage medium for an electric vehicle, which are used to solve the zero-crossing impact problem of the electric vehicle.

In a first aspect, an embodiment of the present application provides a motor control method for an electric vehicle, comprising: obtaining vehicle operation information of the electric vehicle; determining a basic motor torque of a motor of the electric vehicle based on the vehicle operation information; determining a zero-crossing compensation torque of the motor based on the basic motor torque; determining a corrected motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque; and controlling the output torque of the motor to perform zero crossing based on the corrected motor torque.

In one possible implementation, the vehicle operation information includes at least one of the following: vehicle speed, vehicle acceleration, motor speed, wheel speed, accelerator pedal position, brake pedal position, brake master cylinder pressure, braking force, braking torque, slope, creep setting status, energy recovery setting status, single-pedal driving mode setting status, and driving mode setting status.

In one possible implementation, the basic motor torque of the electric vehicle's motor is determined based on vehicle operation information, including: determining the basic motor torque according to an accelerator pedal position, a brake pedal position, a creep setting state, an energy recovery setting state, a single-pedal driving mode setting state and a driving mode setting state, as well as a vehicle speed and/or a motor speed and/or a wheel speed.

In one possible implementation, the zero-crossing compensation torque of the motor is determined based on the basic motor torque, including: determining the zero-crossing compensation torque based on braking force, slope, vehicle speed, motor speed and basic motor torque; or determining the zero-crossing compensation torque based on vehicle speed, vehicle acceleration, motor speed and basic motor torque.

In one possible implementation, the zero-crossing compensation torque is determined based on the braking force, slope, vehicle speed, motor speed and basic motor torque, including: determining the zero-crossing start time, the zero-crossing end time, the basic motor torque at the zero-crossing start time, the zero-crossing platform torque and the duration of the zero-crossing platform torque based on the braking force, slope, vehicle speed, motor speed and basic motor torque; determining the zero-crossing compensation torque based on the zero-crossing start time, the zero-crossing end time, the basic motor torque at the zero-crossing start time, the zero-crossing platform torque and the duration of the zero-crossing platform torque.

In a possible implementation, it also includes: determining the start time of the zero crossing compensation torque, the end time of the zero crossing compensation torque, and the end time of the zero crossing under the corrected motor torque control based on the zero crossing start time, the zero crossing end time, the basic motor torque at the zero crossing start time, the zero crossing platform torque, and the duration of the zero crossing platform torque.

In one possible implementation, the zero-crossing compensation torque is determined based on the braking force, slope, vehicle speed, motor speed and basic motor torque, including: determining a first product of the braking force and a braking force conversion coefficient, wherein the braking force conversion coefficient has a mapping relationship with the slope, vehicle speed, motor speed and basic motor torque; determining a second product of the slope and the slope conversion coefficient, wherein the slope conversion coefficient has a mapping relationship with the braking force, vehicle speed, motor speed and basic motor torque; and determining the zero-crossing compensation torque based on a first sum of the first product and the second product.

In one possible implementation, the zero-crossing compensation torque is determined based on the vehicle speed, the vehicle acceleration, the motor speed, and the basic motor torque, including: determining the vehicle acceleration and the vehicle acceleration conversion The third product of the coefficient, the vehicle acceleration conversion coefficient has a mapping relationship with the vehicle acceleration, vehicle speed, motor speed and basic motor torque; based on the third product, the zero-crossing compensation torque is determined.

In a possible implementation, determining a corrected motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque includes: determining the corrected motor torque according to a second sum of the basic motor torque and the zero-crossing compensation torque.

In a possible implementation, based on the corrected motor torque, the output torque of the motor is controlled to pass through zero, including: controlling the motor to output according to the corrected motor torque to pass through zero.

In a second aspect, an embodiment of the present application provides a motor control device for an electric vehicle, comprising: an acquisition module for acquiring vehicle operation information of the electric vehicle; a first determination module for determining the basic motor torque of the motor of the electric vehicle based on the vehicle operation information; a second determination module for determining the zero-crossing compensation torque of the motor based on the basic motor torque; a third determination module for determining the corrected motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque; and a control module for controlling the output torque of the motor to perform zero crossing based on the corrected motor torque.

In a third aspect, an embodiment of the present application provides an electric vehicle, comprising: a processor, and a memory connected to the processor; the memory stores computer execution instructions; the processor executes the computer execution instructions stored in the memory to implement the motor control method of the electric vehicle as in the first aspect.

In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer execution instructions are stored. When the computer execution instructions are executed, they are used to implement the motor control method of the electric vehicle of the first aspect.

In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed, implements the motor control method of an electric vehicle as in the first aspect.

The motor control method, device and storage medium of the electric vehicle provided in the embodiments of the present application determine the basic motor torque through vehicle operation information, determine the zero-crossing compensation torque of the motor through the basic motor torque, and determine the corrected motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque, so as to correct the motor torque of the electric vehicle according to the corrected motor torque. In this way, the corrected motor torque can be used to make the motor cross zero, so as to reduce or even eliminate the tooth gap impact caused by the switching of the positive and negative torques of the motor, that is, reduce or even eliminate the zero-crossing impact.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, A brief introduction is given to the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

FIG1 is a schematic diagram of an application scenario of a motor control method for an electric vehicle provided in an embodiment of the present application;

FIG2 is a flow chart of a motor control method for an electric vehicle provided in an embodiment of the present application;

FIG3 is a schematic diagram of the zero-crossing performance of a motor under basic motor torque control provided by the related art;

4 is a schematic diagram of the start time of the zero-crossing compensation torque when the basic motor torque provided by an embodiment of the present application transitions from positive torque to negative torque and the vehicle speed or wheel speed decreases;

5 is a schematic diagram of the start time of the zero-crossing compensation torque when the basic motor torque provided by an embodiment of the present application transitions from positive torque to negative torque and the vehicle speed or wheel speed increases;

6 is a schematic diagram of the start time of the zero-crossing compensation torque when the basic motor torque provided by an embodiment of the present application transitions from negative torque to positive torque and the vehicle speed or wheel speed decreases;

7 is a schematic diagram of the start time of the zero-crossing compensation torque when the basic motor torque provided by an embodiment of the present application transitions from negative torque to positive torque and the vehicle speed or wheel speed increases;

FIG8 is a schematic diagram showing a comparison between the zero-crossing performance of a motor under the modified motor torque control and the zero-crossing performance of a motor under the basic motor torque control provided by an embodiment of the present application;

FIG9 is a schematic structural diagram of a motor control device for an electric vehicle provided in an embodiment of the present application;

Fig. 10 is a block diagram of an electric vehicle according to an exemplary embodiment.

DETAILED DESCRIPTION

In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments made by ordinary technicians in this field under the enlightenment of the embodiments belong to the scope of protection of the present application.

The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive His inclusion, for example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or apparatus.

The following first explains the terms involved in this application.

Zero crossing: The conversion process between positive torque and negative torque of the motor.

The related technologies provided in the background technology have at least the following technical problems:

Using a fixed torque or a slower torque change rate to perform zero-crossing control to reduce the zero-crossing impact is generally called zero-crossing platform torque control. However, this method does not take into account the changes in the vehicle's motion state caused by braking force, ramps, vehicle resistance (such as changes in vehicle resistance caused by temperature changes) or road resistance changes, causing the motor to cross zero outside the control range of the zero-crossing platform torque, resulting in a problem of increased zero-crossing impact of the motor when the braking force, ramps, vehicle resistance or road resistance changes.

In response to the problems in the related technology, the present application proposes a motor control method for an electric vehicle, which determines the basic motor torque through vehicle operation information, and determines the zero-crossing compensation torque of the motor through the basic motor torque, and determines the corrected motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque, so as to correct the motor torque of the electric vehicle according to the corrected motor torque. In this way, the corrected motor torque can be used to make the motor cross zero, so as to reduce or even eliminate the tooth gap impact caused by the switching of the positive and negative torques of the motor, that is, reduce or even eliminate the zero-crossing impact.

In one embodiment, the motor control method of the electric vehicle can be applied in an application scenario. FIG1 is a schematic diagram of an application scenario of the motor control method of the electric vehicle provided in an embodiment of the present application. As shown in FIG1, the controller can receive vehicle operation information, and determine the basic motor torque and the zero-crossing compensation torque according to the vehicle operation information, and determine the corrected motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque, and then output the corrected motor torque to the motor. After receiving the corrected motor torque, the motor outputs the corrected motor torque, thereby achieving zero crossing of the motor.

In the above scenario, since the zero-crossing impact of the motor is positively correlated with the maximum speed difference of the motor speed, the greater the maximum speed difference of the motor speed, the greater the zero-crossing impact. Under the basic motor torque control, the maximum speed difference of the motor speed is large, which will cause the zero-crossing impact of the motor to be large, affecting the driving comfort of the user. Therefore, it is necessary to determine the zero-crossing compensation torque to correct the basic motor torque, so that under the corrected motor torque control, the maximum speed difference of the motor speed will be smaller than the maximum speed difference of the motor speed under the basic motor torque control, so that relative to the basic motor torque, under the corrected motor torque control, the maximum speed difference of the motor speed is reduced, and therefore, the zero-crossing impact of the motor will be reduced or even eliminated.

In combination with the above scenarios, the technical solution of the motor control method of the electric vehicle provided by the present application is described in detail through several specific embodiments below.

The present application provides a motor control method for an electric vehicle. FIG2 is a flow chart of the motor control method for an electric vehicle provided in an embodiment of the present application. As shown in FIG2 , the method includes the following steps:

S201: Acquire vehicle operation information of the electric vehicle.

In this step, the vehicle operation information of the electric vehicle can be used to determine various torques, such as basic motor torque, zero-crossing compensation torque, corrected motor torque, etc.

S202: Determine a basic motor torque of a motor of the electric vehicle based on vehicle operation information.

In this step, the basic motor torque can be a control torque that does not consider the braking force and slope, or the influence of the vehicle deceleration on zero crossing, or a control torque under level road and no braking conditions. The user's required torque can be determined through vehicle operation information, and the required torque is the basic motor torque.

S203: Determine the zero-crossing compensation torque of the motor based on the basic motor torque.

In this step, after determining the basic motor torque, since the zero-crossing impact of the motor is positively correlated with the maximum speed difference of the motor speed, the greater the maximum speed difference of the motor speed, the greater the zero-crossing impact. Under the control of the basic motor torque, the maximum speed difference of the motor speed is large, which will cause the zero-crossing impact of the motor to be large, affecting the user's driving comfort. Therefore, it is necessary to determine the zero-crossing compensation torque of the motor to correct the basic motor torque, so as to reduce the maximum speed difference of the motor, thereby reducing or even eliminating the zero-crossing impact of the motor.

S204: Determine a corrected motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque.

In this step, the zero-crossing compensation torque can be used to compensate for the zero-crossing of the motor. Therefore, after determining the basic motor torque and the zero-crossing compensation torque, the basic motor torque can be corrected based on the zero-crossing compensation torque to obtain the corrected motor torque.

S205: Based on the corrected motor torque, control the output torque of the motor to perform zero crossing.

In this step, the basic motor torque is corrected by the zero-crossing compensation torque to obtain the corrected motor torque. Under the control of the corrected motor torque, the maximum speed difference of the motor speed will be smaller than the maximum speed difference of the motor speed under the control of the basic motor torque. Thus, relative to the basic motor torque, under the control of the corrected motor torque, the maximum speed difference of the motor speed is reduced. Therefore, the zero-crossing impact of the motor will be reduced or even eliminated.

The motor control method of the electric vehicle provided in this embodiment determines the basic motor The motor torque is determined by the basic motor torque, and the zero-crossing compensation torque of the motor is determined by the basic motor torque, and the corrected motor torque of the motor is determined based on the basic motor torque and the zero-crossing compensation torque, so that the motor torque of the electric vehicle is corrected according to the corrected motor torque. In this way, the corrected motor torque can be used to make the motor cross zero, so as to reduce or even eliminate the tooth gap impact caused by the positive and negative torque switching of the motor, that is, to reduce or even eliminate the zero-crossing impact.

In one embodiment, the vehicle operation information includes at least one of the following: vehicle speed, vehicle acceleration, motor speed, wheel speed, accelerator pedal position, brake pedal position, brake master cylinder pressure, braking force, braking torque, slope, creep setting status, energy recovery setting status, single-pedal driving mode setting status, and driving mode setting status.

In this scheme, braking force refers to the vehicle braking force provided by the mechanical brake device through friction; vehicle operation information such as vehicle speed, vehicle acceleration, motor speed, wheel speed, slope, etc. can be obtained by measuring the vehicle's own sensors or by measuring equipment outside the vehicle, and vehicle acceleration can also be obtained by calculating the vehicle speed. The accelerator pedal position and the brake pedal position can also be measured by sensors or calculated based on the pedal pressure. The brake master cylinder pressure and the brake torque can also be calculated or measured. The creep setting state can refer to whether the vehicle is set to the creep state. If the vehicle is set to the creep state, the vehicle will eventually move at the creep speed after releasing the brake pedal and the accelerator pedal. The energy recovery setting state can refer to whether the vehicle is set to the energy recovery state and the set energy recovery level. The single-pedal driving mode setting state can refer to whether the vehicle is set to the single-pedal driving mode setting state. The driving mode setting state can refer to which driving mode the vehicle is set to, for example, comfort mode, economy mode, etc.

Optionally, in actual use, all or part of the above vehicle operation information can be used to participate in the calculation of each torque. For example, the motor speed can be used as the speed input, and the vehicle speed or wheel speed can be used as the speed input; that is, the braking force can be used as the braking signal input, and the braking torque or the brake master cylinder pressure or the brake pedal position can be used as the braking signal input; or the vehicle acceleration can be used to replace the braking signal and the slope signal.

Optionally, the basic motor torque can be corrected by vehicle operation information to obtain a corrected motor torque, so that the corrected motor torque can be used to perform zero crossing of the motor to reduce or even eliminate the tooth gap impact caused by the switching of the positive and negative torque of the motor, that is, reduce or even eliminate the zero crossing impact.

In one embodiment, based on the vehicle operation information, determining the basic motor torque of the electric vehicle motor includes: determining the basic motor torque of the electric vehicle motor based on the accelerator pedal position, the brake pedal position, the creep setting state, the energy recovery setting state, the state, the one-pedal driving mode setting state and the driving mode setting state, as well as the vehicle speed and/or the motor speed and/or the wheel speed, determine the basic motor torque.

In this scheme, there is a corresponding relationship between the accelerator pedal position, brake pedal position, creep setting state, energy recovery setting state, single-pedal driving mode setting state, driving mode setting state, as well as vehicle states and vehicle setting states such as vehicle speed and/or motor speed and/or wheel speed, and the basic motor torque. After determining the accelerator pedal position, brake pedal position, creep setting state, energy recovery setting state, single-pedal driving mode setting state, driving mode setting state, as well as vehicle speed and/or motor speed and/or wheel speed, the basic motor torque can be determined based on the corresponding relationship.

Optionally, after determining the basic motor torque, since the zero-crossing impact of the motor is positively correlated with the maximum speed difference of the motor speed, the greater the maximum speed difference of the motor speed, the greater the zero-crossing impact. Under the basic motor torque control, the maximum speed difference of the motor speed is large, which will cause the zero-crossing impact of the motor to be large, affecting the driving comfort of the user. As shown in Figure 3, Figure 3 is a schematic diagram of the zero-crossing performance of the motor under the basic motor torque control provided by the relevant technology.

In FIG3 , ΔV can be expressed as the maximum speed difference of the motor speed, and the magnitude of the zero-crossing impact is positively correlated with the magnitude of ΔV. _{t 0} can be expressed as the start time of zero-crossing. t ₁ can be expressed as the end time of zero-crossing. _{T bas} can be expressed as the basic motor torque. _{T bas0} can be expressed as the basic motor torque at the start time of zero-crossing. T _bas1 can be expressed as the zero-crossing platform torque under the basic motor torque control. _{Δt bas1} can be expressed as the duration of the zero-crossing platform torque under the basic motor torque control.

As can be seen from Figure 3, the maximum speed difference of the motor speed is large, that is, the change of the motor speed is large, which will cause a large zero-crossing impact of the motor, affecting the driving comfort of the user. Therefore, after determining the basic motor torque, the basic motor torque can be corrected to reduce or even eliminate the zero-crossing impact of the motor, thereby improving the driving comfort of the user.

In one embodiment, the zero-crossing compensation torque of the motor is determined based on the basic motor torque, including: determining the zero-crossing compensation torque based on braking force, slope, vehicle speed, motor speed and basic motor torque; or determining the zero-crossing compensation torque based on vehicle speed, vehicle acceleration, motor speed and basic motor torque.

In this scheme, since the motor has a large zero-crossing impact under the basic motor torque control, it is necessary to determine the motor's zero-crossing compensation torque to correct the basic motor torque, so that the maximum speed difference of the motor can be reduced, thereby reducing or even eliminating the motor's zero-crossing impact. When determining the zero-crossing compensation torque, the braking force, slope, vehicle speed, motor speed, and basic motor torque can be used to determine the zero-crossing compensation torque. The zero-crossing compensation torque may be calculated based on information such as vehicle speed, vehicle acceleration, basic motor torque, and motor speed.

In one embodiment, the zero-crossing compensation torque is determined based on the braking force, slope, vehicle speed, motor speed and basic motor torque, including: determining the zero-crossing start time, the zero-crossing end time, the basic motor torque at the zero-crossing start time, the zero-crossing platform torque and the duration of the zero-crossing platform torque based on the braking force, slope, vehicle speed, motor speed and basic motor torque; determining the zero-crossing compensation torque based on the zero-crossing start time, the zero-crossing end time, the basic motor torque at the zero-crossing start time, the zero-crossing platform torque and the duration of the zero-crossing platform torque.

In this solution, in actual use, the zero-crossing start time t 0 , the zero-crossing end time t ₁ , the basic motor torque T bas0 at the zero-crossing start time, the zero-crossing platform torque T _bas1 , and the duration Δt _bas1 of the zero-crossing platform torque can be calculated according to vehicle operation information such as braking force and slope ₍ or vehicle acceleration), basic motor torque, vehicle speed (or wheel speed), and _{motor speed} . That is, the corresponding relationship between the braking force and the slope (or vehicle acceleration), the basic motor torque, the vehicle speed (or the wheel speed), the motor speed and other vehicle operation information and the zero-crossing start time t ₀ , the zero-crossing end time t ₁ , the basic motor torque T _bas0 at the zero-crossing start time, the zero-crossing platform torque T _bas1 , and the duration Δt _bas1 of the zero-crossing platform torque can be obtained through calculation. In this way, after determining the braking force and the slope (or vehicle acceleration), the basic motor torque, the vehicle speed (or the wheel speed), the motor speed and other vehicle operation information, the zero-crossing start time t ₀ , the zero-crossing end time t ₁ , the basic motor torque T _bas0 at the zero-crossing start time, the zero-crossing platform torque T _bas1 , and the duration Δt _bas1 of the zero-crossing platform torque can be determined according to the corresponding relationship.

Optionally, the test may also be performed in an actual test environment to obtain the corresponding relationship between the braking force and slope (or vehicle acceleration), basic motor torque, vehicle speed (or wheel speed) and other vehicle operation information and the zero-crossing start time t ₀ , the zero-crossing end time t ₁ , the basic motor torque T _bas0 at the zero-crossing start time, the zero-crossing platform torque T _bas1 , and the duration Δt _bas1 of the zero-crossing platform torque.

In an optional implementation, since there is a corresponding relationship between the zero-crossing start time t ₀ , the zero-crossing end time t ₁ , the basic motor torque T _bas0 at the zero-crossing start time, the zero-crossing platform torque T _bas1 , the duration Δt _bas1 of the zero-crossing platform torque, and the zero-crossing compensation torque T _corr , the zero-crossing compensation torque T corr can be obtained after determining the zero-crossing start time t ₀ , the zero-crossing end time t ₁ , the basic motor torque T _bas0 at the zero-crossing start time, the zero-crossing platform torque T _bas1 , and the duration Δt _bas1 of the zero-crossing platform _torque .

Optionally, since the zero-crossing impact of the motor is positively correlated with the maximum speed difference of the motor speed, the greater the maximum speed difference of the motor speed, the greater the zero-crossing impact, and under the basic motor torque control, the motor The maximum speed difference of the motor speed is large, which will cause a large zero-crossing impact of the motor and affect the user's driving comfort. Therefore, it is necessary to determine the zero-crossing compensation torque of the motor to correct the basic motor torque, so that the maximum speed difference of the motor can be reduced, thereby reducing or even eliminating the zero-crossing impact of the motor.

In one embodiment, it also includes: determining the start time of the zero crossing compensation torque, the end time of the zero crossing compensation torque, and the end time of the zero crossing under the corrected motor torque control based on the zero crossing start time, the zero crossing end time, the basic motor torque at the zero crossing start time, the zero crossing platform torque, and the duration of the zero crossing platform torque.

In this scheme, when the zero-crossing compensation torque is determined according to the zero-crossing start time t ₀ , the zero-crossing end time t ₁ , the basic motor torque T _bas0 at the zero-crossing start time, the zero-crossing platform torque T _bas1 , and the duration Δt _bas1 of the zero-crossing platform torque, since the zero-crossing start time t ₀ , the zero-crossing end time t ₁ , the basic motor torque T _bas0 at the zero-crossing start time, the zero-crossing platform torque T _bas1 , and the duration Δt _bas1 of the zero-crossing platform torque also have a corresponding relationship with the starting time t _0' of the zero-crossing compensation torque, the zero-crossing end time t _1' under the correction motor torque control, and the ending time t ₂ of the zero-crossing compensation torque, therefore, after determining the zero-crossing start time t ₀ , the zero-crossing end time t ₁ , the basic motor torque T _bas0 at the zero-crossing start time, the zero-crossing platform torque T _bas1 , and the duration Δt _bas1 of the zero-crossing platform torque, the starting time t _0' of the zero-crossing compensation torque can also be obtained. , the zero-crossing end time t _1' under the correction motor torque control, and the end time t ₂ of the zero-crossing compensation torque.

Optionally, by determining these moments, it is possible to determine at which moment the zero-crossing compensation torque starts, at which moment the zero-crossing compensation torque ends, and at which moment the zero-crossing ends under the corrected motor torque control, thereby improving the user's driving experience.

In an optional implementation, as shown in FIG4 , FIG4 is a schematic diagram of the start time of the zero-crossing compensation torque when the basic motor torque provided by the embodiment of the present application transitions from positive torque to negative torque and the vehicle speed or wheel speed decreases. When the basic motor torque T _bas transitions from positive torque to negative torque and the vehicle speed (or wheel speed) decreases, T _corr , t _0' , t _1' , t ₂ can be determined by the following method:

Preferably, t _0′ =t ₀ −Δt _bas1 ; optionally, t ₀ −Δt _bas1 <t _0′ <t ₀ .

Preferably, T _corr =T _bas0 -T _bas1 ; optionally, T _bas0 -| _{T bas1} |≤T _corr <0.

After t _0' and T _corr are determined, the zero-crossing end time t _1' under the correction motor torque control can be determined by calculation according to the corresponding relationship or by actual testing.

Preferably, t ₂ =t _1' ; optionally, t _0' <t ₂ <t _1' ; optionally, t _1' <t ₂ .

In practical applications, T _corr , t _0′ , and t ₂ may be calibrated and adjusted according to actual vehicle zero-crossing performance.

In an optional implementation, as shown in FIG5 , FIG5 is a schematic diagram of the start time of the zero-crossing compensation torque when the basic motor torque provided by the embodiment of the present application transitions from positive torque to negative torque and the vehicle speed or wheel speed increases. When the basic motor torque T _bas transitions from positive torque to negative torque and the vehicle speed (or wheel speed) increases, T _corr , t _0' , t _1' , t ₂ can be determined by the following method:

Preferably, t ₀ ＜t _0′ ＜t ₁ .

Preferably, T _corr =T _bas0 -T _bas1 ; optionally, 0<T _corr <T _bas0 +|T _bas1 |.

After t _0' and T _corr are determined, the zero-crossing end time t _1' under the correction motor torque control can be determined by calculation according to the corresponding relationship or by actual testing.

Preferably, t ₂ =t _1' ; optionally, t _0' <t ₂ <t ₁ ; optionally, t ₁ <t ₂ <t _1' ; optionally, t _1' <t ₂ .

In practical applications, T _corr , t _0′ , and t ₂ may be calibrated and adjusted according to actual vehicle zero-crossing performance.

In an optional implementation, as shown in FIG6 , FIG6 is a schematic diagram of the start time of the zero-crossing compensation torque when the basic motor torque provided by the embodiment of the present application transitions from negative torque to positive torque and the vehicle speed or wheel speed decreases. When the basic motor torque T _bas transitions from negative torque to positive torque and the vehicle speed (or wheel speed) decreases, T _corr , t _0' , t _1' , t ₂ can be determined by the following method:

Preferably, t ₀ ＜t _0′ ＜t ₁ .

Preferably, T _corr =T _bas0 -T _bas1 ; optionally, T _bas0 -| _{T bas1} |<T _corr <0.

After t _0' and T _corr are determined, the zero-crossing end time t _1' under the correction motor torque control can be determined by calculation according to the corresponding relationship or by actual testing.

Preferably, t ₂ =t _1' ; optionally, t _0' <t ₂ <t ₁ ; optionally, t ₁ <t ₂ <t _1' ; optionally, t _1' <t ₂ .

In practical applications, T _corr , t _0′ , and t ₂ may be calibrated and adjusted according to actual vehicle zero-crossing performance.

In an optional implementation, as shown in FIG7 , FIG7 is a schematic diagram of the start time of the zero-crossing compensation torque when the basic motor torque provided by the embodiment of the present application transitions from negative torque to positive torque and the vehicle speed or wheel speed increases. When the basic motor torque T _bas transitions from negative torque to positive torque and the vehicle speed (or wheel speed) increases, T _corr , t _0' , t _1' , t ₂ can be determined by the following method:

Preferably, t _0′ =t ₀ −Δt _bas1 ; optionally, t ₀ −Δt _bas1 <t _0′ <t ₀ .

Preferably, T _corr =T _bas0 -T _bas1 ; optionally, 0≤T _corr <T _bas0 +|T _bas1 |.

After t _0' and T _corr are determined, the zero-crossing end time t _1' under the correction motor torque control can be determined by calculation according to the corresponding relationship or by actual testing.

Preferably, t ₂ =t _1' ; optionally, t _0' <t ₂ <t _1' ; optionally, t _1' <t ₂ ;.

In practical applications, T _corr , t _0′ , and t ₂ may be calibrated and adjusted according to actual vehicle zero-crossing performance.

In one embodiment, the zero-crossing compensation torque is determined based on the braking force, slope, vehicle speed, motor speed and basic motor torque, including: determining a first product of the braking force and a braking force conversion coefficient, wherein the braking force conversion coefficient has a mapping relationship with the slope, vehicle speed, motor speed and basic motor torque; determining a second product of the slope and the slope conversion coefficient, wherein the slope conversion coefficient has a mapping relationship with the braking force, vehicle speed, motor speed and basic motor torque; and determining the zero-crossing compensation torque according to a first sum of the first product and the second product.

In this solution, the zero-crossing compensation torque T _corr may be a calculated value, and T _corr may be obtained by real-time calculation based on the braking force, slope, vehicle speed (or wheel speed), motor speed, and basic motor torque. The calculation formula may be as follows:
T _corr = F _brak * A + α * B

Wherein, F _brak may represent the braking force; α may represent the slope; A may represent the braking force conversion coefficient; and B may represent the slope conversion coefficient. A may be a fixed coefficient or a coefficient having a mapping relationship with F _brak , vehicle speed, motor speed, and basic motor torque; B may be a fixed coefficient or a coefficient having a mapping relationship with α, vehicle speed, motor speed, and basic motor torque.

Optionally, since the motor has a large zero-crossing impact under basic motor torque control, it is necessary to determine the motor's zero-crossing compensation torque to correct the basic motor torque, thereby reducing the motor's maximum speed difference and thus reducing or even eliminating the motor's zero-crossing impact.

In an optional implementation, T _corr may also be a preset value, which represents a mapping relationship between T _corr and braking force and slope (or vehicle acceleration), vehicle speed (or wheel speed), motor speed and basic motor torque, and may be obtained by looking up one or more mapping tables stored in the storage unit.

In one embodiment, the zero-crossing compensation torque is determined based on the vehicle speed, vehicle acceleration, motor speed and basic motor torque, including: determining the third product of the vehicle acceleration and the vehicle acceleration conversion coefficient, the vehicle acceleration conversion coefficient and the vehicle acceleration, vehicle speed, motor speed and basic motor torque are mapped to each other; and determining the zero-crossing compensation torque based on the third product.

In this solution, the zero-crossing compensation torque T _corr can be a calculated value, which can be obtained by the vehicle speed, vehicle The vehicle acceleration, motor speed and basic motor torque are used to perform real-time calculation to obtain T _corr . The calculation formula can be as follows:
T _corr = a*K

Among them, a can represent the vehicle acceleration; K can represent the vehicle acceleration conversion coefficient; K can be a fixed coefficient or a coefficient that has a mapping relationship with a, vehicle speed, motor speed, and basic motor torque.

Optionally, since the motor has a large zero-crossing impact under basic motor torque control, it is necessary to determine the motor's zero-crossing compensation torque to correct the basic motor torque, thereby reducing the motor's maximum speed difference and thus reducing or even eliminating the motor's zero-crossing impact.

In one embodiment, determining a modified motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque includes: determining the modified motor torque according to a second sum of the basic motor torque and the zero-crossing compensation torque.

In this scheme, after determining the basic motor torque and the zero-crossing compensation torque, the corrected motor torque can be determined by the following formula:
T _conf = T _bas + T _corr

Wherein, T _conf may represent the corrected motor torque. After the basic motor torque is corrected by the zero-crossing compensation torque to obtain the corrected motor torque, under the control of the corrected motor torque, the maximum speed difference of the motor speed will be less than the maximum speed difference of the motor speed under the control of the basic motor torque, so that relative to the basic motor torque, under the control of the corrected motor torque, the maximum speed difference of the motor speed is reduced, and therefore, the zero-crossing impact of the motor will be reduced or even eliminated. As shown in FIG8 , FIG8 is a schematic diagram for comparing the zero-crossing performance of the motor under the control of the corrected motor torque and the zero-crossing performance of the motor under the control of the basic motor torque, provided in an embodiment of the present application.

In FIG8 , T _corr may represent the zero-crossing compensation torque. ΔV' may represent the maximum speed difference of the motor speed under the modified motor torque control. T _conf may represent the modified motor torque. _{t 0'} may represent the start time of the zero-crossing compensation torque. _{t 1'} may represent the end time of the zero-crossing compensation torque under the modified motor torque control. t ₂ may represent the end time of the zero-crossing compensation torque.

It can be seen from Figure 8 that compared with the maximum speed difference of the motor under basic motor torque control, the maximum speed difference ΔV’ of the motor under modified motor torque control is significantly smaller. Therefore, under modified motor torque control, the zero-crossing impact of the motor will be reduced or even eliminated.

In one embodiment, based on the corrected motor torque, the output torque of the motor is controlled to perform Zero, including: controlling the motor to output according to the corrected motor torque to pass zero.

In this solution, after obtaining the corrected motor torque, in order to reduce or even eliminate the zero-crossing impact of the motor, the motor can be controlled to output torque according to the corrected motor torque, so that when the motor crosses zero, the impact can be significantly reduced or even eliminated.

The motor control method of the electric vehicle provided in the present application calculates the basic motor torque and the zero-crossing compensation torque by acquiring the vehicle operation information, and then calculates the corrected motor torque by the basic motor torque and the zero-crossing compensation torque. In this way, the output torque of the motor can be controlled to pass through zero by the corrected motor torque, thereby reducing or eliminating the zero-crossing impact of the motor.

It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and provide corresponding operation entrances for users to choose to authorize or refuse.

The present application also provides a motor control device for an electric vehicle. FIG9 is a schematic diagram of the structure of the motor control device for an electric vehicle provided in an embodiment of the present application. As shown in FIG9 , the motor control device 900 for an electric vehicle includes:

The acquisition module 901 is used to obtain the vehicle operation information of the electric vehicle;

A first determination module 902 is used to determine a basic motor torque of a motor of the electric vehicle based on vehicle operation information;

A second determination module 903 is used to determine the zero-crossing compensation torque of the motor based on the basic motor torque;

A third determination module 904 is used to determine a modified motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque;

The control module 905 is used to control the output torque of the motor to perform zero crossing based on the corrected motor torque.

Optionally, the vehicle operation information includes at least one of the following: vehicle speed, vehicle acceleration, motor speed, wheel speed, accelerator pedal position, brake pedal position, brake master cylinder pressure, braking force, braking torque, slope, creep setting status, energy recovery setting status, single-pedal driving mode setting status, and driving mode setting status.

Optionally, when determining the basic motor torque of the motor of the electric vehicle based on the vehicle operation information, the first determination module 902 is specifically used to: The basic motor torque is determined based on the state, energy recovery setting state, single-pedal driving mode setting state and driving mode setting state, as well as the vehicle speed and/or the motor speed and/or the wheel speed.

Optionally, when determining the zero-crossing compensation torque of the motor based on the basic motor torque, the second determination module 903 is specifically used to: determine the zero-crossing compensation torque based on braking force, slope, vehicle speed, motor speed and basic motor torque; or determine the zero-crossing compensation torque based on vehicle speed, vehicle acceleration, motor speed and basic motor torque.

Optionally, when determining the zero-crossing compensation torque based on the braking force, slope, vehicle speed, motor speed and basic motor torque, the second determination module 903 is specifically used to: determine the zero-crossing start time, the zero-crossing end time, the basic motor torque at the zero-crossing start time, the zero-crossing platform torque and the duration of the zero-crossing platform torque based on the braking force, slope, vehicle speed, motor speed and basic motor torque; determine the zero-crossing compensation torque based on the zero-crossing start time, the zero-crossing end time, the basic motor torque at the zero-crossing start time, the zero-crossing platform torque and the duration of the zero-crossing platform torque.

Optionally, it also includes: a fourth determination module, which is used to determine the start time of the zero crossing compensation torque, the end time of the zero crossing compensation torque, and the end time of the zero crossing under the corrected motor torque control based on the zero crossing start time, the zero crossing end time, the basic motor torque at the zero crossing start time, the zero crossing platform torque, and the duration of the zero crossing platform torque.

Optionally, when determining the zero-crossing compensation torque based on the braking force, slope, vehicle speed, motor speed and basic motor torque, the second determination module 903 is specifically used to: determine the first product of the braking force and the braking force conversion coefficient, and there is a mapping relationship between the braking force conversion coefficient and the slope, vehicle speed, motor speed and basic motor torque; determine the second product of the slope and the slope conversion coefficient, and there is a mapping relationship between the slope conversion coefficient and the braking force, vehicle speed, motor speed and basic motor torque; determine the zero-crossing compensation torque based on the first sum of the first product and the second product.

Optionally, when determining the zero-crossing compensation torque based on the vehicle speed, vehicle acceleration, motor speed and basic motor torque, the second determination module 903 is specifically used to: determine the third product of the vehicle acceleration and the vehicle acceleration conversion coefficient, the vehicle acceleration conversion coefficient having a mapping relationship with the vehicle acceleration, vehicle speed, motor speed and basic motor torque; and determine the zero-crossing compensation torque based on the third product.

Optionally, when determining the corrected motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque, the third determination module 904 is specifically used to: determine the corrected motor torque according to a second sum of the basic motor torque and the zero-crossing compensation torque.

Optionally, the control module 905 controls the output torque of the motor based on the corrected motor torque. When zero crossing is performed, it is specifically used to: control the motor to output according to the corrected motor torque to perform zero crossing.

The motor control device of the electric vehicle provided in this embodiment is used to execute the technical solution of the motor control method of the electric vehicle in the aforementioned method embodiment. Its implementation principle and technical effect are similar and will not be repeated here.

The embodiment of the present application also provides an electric vehicle. FIG10 is a block diagram of an electric vehicle according to an exemplary embodiment. As shown in FIG10 , the electric vehicle 1000 includes:

Processor 1011, memory 1012, and interactive interface 1013;

Among them, the processor 1011 is connected to the memory 1012 and the interactive interface 1013; the memory 1012 is used to store computer-executable instructions executable by the processor 1011; the processor 1011 is configured to execute the technical solution in the motor control method of the aforementioned electric vehicle by executing computer-executable instructions; the interactive interface 1013 provides an interface between the processor 1011 and the peripheral interface module.

Optionally, the memory 1012 may be independent or integrated with the processor 1011 .

Optionally, when the memory 1012 is a device independent of the processor 1011, the electric vehicle 1000 may further include: a bus for connecting the above devices.

Optionally, the memory may be, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable read-only memory (EEPROM), etc. The memory is used to store programs, and the processor executes the programs after receiving the execution instruction. Furthermore, the software programs and modules in the above-mentioned memory may also include an operating system, which may include various software components and/or drivers for managing system tasks (such as memory management, storage device control, power management, etc.), and may communicate with various hardware or software components to provide an operating environment for other software components.

Optionally, the processor may be an integrated circuit chip having signal processing capability. The above-mentioned processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc. The disclosed methods, steps, and logic block diagrams in the embodiments of the present application may be implemented or executed. The general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

An embodiment of the present application also provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed, they are used to implement the technical solution of the motor control method of the electric vehicle provided in the aforementioned method embodiment.

An embodiment of the present application also provides a computer program product, including a computer program, which, when executed, implements the technical solution of the motor control method of an electric vehicle provided in the method embodiment.

Those skilled in the art can understand that all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk and other media that can store program codes.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims (14)

A motor control method for an electric vehicle, characterized by comprising: Obtain vehicle operation information of electric vehicles; determining a basic motor torque of a motor of the electric vehicle based on the vehicle operation information; Determining a zero-crossing compensation torque of the motor based on the basic motor torque; determining a modified motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque; Based on the corrected motor torque, the output torque of the motor is controlled to perform a zero crossing. The motor control method according to claim 1, characterized in that the vehicle operation information includes at least one of the following: Vehicle speed, vehicle acceleration, motor speed, wheel speed, accelerator pedal position, brake pedal position, brake master cylinder pressure, braking force, brake torque, slope, creep setting status, energy recovery setting status, single-pedal driving mode setting status, driving mode setting status. The motor control method according to claim 2, characterized in that the determining the basic motor torque of the motor of the electric vehicle based on the vehicle operation information comprises: The basic motor torque is determined based on the accelerator pedal position, the brake pedal position, the creep setting state, the energy recovery setting state, the single-pedal driving mode setting state and the driving mode setting state, as well as the vehicle speed and/or the motor speed and/or the wheel speed. The motor control method according to claim 2 or 3, characterized in that the determining the zero-crossing compensation torque of the motor based on the basic motor torque comprises: determining the zero-crossing compensation torque based on the braking force, the slope, the vehicle speed, the motor speed and the basic motor torque; or, The zero-crossing compensation torque is determined based on the vehicle speed, the vehicle acceleration, the motor speed, and the base motor torque. The motor control method according to claim 4, characterized in that the determining the zero-crossing compensation torque based on the braking force, the slope, the vehicle speed, the motor speed and the basic motor torque comprises: Based on the braking force, the slope, the vehicle speed, the motor speed and the basic motor torque, determine the zero-crossing start time, the zero-crossing end time, the basic motor torque at the zero-crossing start time, the zero-crossing platform torque and the duration of the zero-crossing platform torque; The zero-crossing compensation torque is determined based on the zero-crossing start time, the zero-crossing end time, the basic motor torque at the zero-crossing start time, the zero-crossing platform torque, and the duration of the zero-crossing platform torque. The motor control method according to claim 5, further comprising: Based on the zero-crossing start time, the zero-crossing end time, the basic motor torque at the zero-crossing start time, the zero-crossing platform torque and the duration of the zero-crossing platform torque, the start time of the zero-crossing compensation torque, the end time of the zero-crossing compensation torque and the zero-crossing end time under the corrected motor torque control are determined. The motor control method according to claim 4, characterized in that the determining the zero-crossing compensation torque based on the braking force, the slope, the vehicle speed, the motor speed and the basic motor torque comprises: Determine a first product of the braking force and a braking force conversion coefficient, wherein the braking force conversion coefficient has a mapping relationship with the slope, the vehicle speed, the motor speed, and the basic motor torque; Determine a second product of the slope and a slope conversion coefficient, wherein the slope conversion coefficient has a mapping relationship with the braking force, the vehicle speed, the motor speed, and the basic motor torque; The zero-crossing compensation torque is determined according to a first sum of the first product and the second product. The motor control method according to claim 4, characterized in that the determining the zero-crossing compensation torque based on the vehicle speed, the vehicle acceleration, the motor speed and the basic motor torque comprises: Determining a third product of the vehicle acceleration and a vehicle acceleration conversion coefficient, wherein the vehicle acceleration conversion coefficient has a mapping relationship with the vehicle acceleration, the vehicle speed, the motor speed, and the basic motor torque; The zero-crossing compensation torque is determined according to the third product. The motor control method according to claim 2 or 3, characterized in that the determining the corrected motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque comprises: The modified motor torque is determined according to a second sum of the basic motor torque and the zero-crossing compensation torque. The motor control method according to claim 2 or 3, characterized in that the step of controlling the output torque of the motor to perform zero crossing based on the corrected motor torque comprises: The motor is controlled to output according to the modified motor torque to perform zero crossing. A motor control device for an electric vehicle, characterized by comprising: A collection module, used to obtain vehicle operation information of the electric vehicle; A first determination module, configured to determine a basic motor torque of a motor of the electric vehicle based on the vehicle operation information; A second determination module, configured to determine a zero-crossing compensation torque of the motor based on the basic motor torque; a third determination module, configured to determine a modified motor torque of the motor based on the basic motor torque and the zero-crossing compensation torque; A control module is used to control the output torque of the motor to perform zero crossing based on the corrected motor torque. An electric vehicle, characterized by comprising: a processor, and a memory connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the motor control method of the electric vehicle as described in any one of claims 1 to 10. A computer-readable storage medium, characterized in that the computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are executed, they are used to implement the motor control method of an electric vehicle as described in any one of claims 1 to 10. A computer program product, comprising a computer program, characterized in that when the computer program is executed, it is used to implement the motor control method of an electric vehicle as described in any one of claims 1 to 10.