Torque control method and related device of electric vehicle

Abstract

The embodiment of the present application provides a torque control method and related device for an electric vehicle, the method comprising: calculating the initial wheel-side demand torque of the current cycle based on the driving information of the current cycle; inputting the target wheel-side demand torque of the previous cycle and the actual motor speed of the current cycle into a state observer to obtain the observed motor speed of the current cycle; calculating the wheel-side compensation torque of the current cycle based on the observed motor speed of the current cycle and the actual motor speed; using the wheel-side compensation torque of the current cycle to compensate the initial wheel-side demand torque of the current cycle to obtain the target wheel-side demand torque of the current cycle, and performing torque control on the electric vehicle based on the target wheel-side demand torque of the current cycle. Through the above scheme, the present application can determine the observed motor speed of the current cycle through the state observer, thereby compensating for the torque, so as to achieve effective control of active damping within the full speed range, thereby reducing speed fluctuations and torque shocks.

Description

Technical Field

[0001] The present application relates to the technical field of electric vehicles, and in particular to a torque control method and related devices for electric vehicles. Background Art

[0002] For pure electric vehicles, frequent switching between low-speed starting, quick accelerator Tip-in, quick accelerator Tip-out and electric power generation mode will cause resonance between the cogging torque and the bracket. The driver and passengers will subjectively feel the low-frequency jitter, which seriously affects the comfort of the entire vehicle.

[0003] In order to solve the above problem, a common solution in the prior art is that the MCU (Motor Control Unit) compensates the actual torque of the motor by detecting the rate of change of the motor speed. However, this method is only effective under low-speed conditions and has obvious limitations. Summary of the invention

[0004] The present application provides a torque control method and related devices for an electric vehicle to solve the problem of poor active damping control effect of the electric vehicle under high speed conditions.

[0005] In a first aspect, the present application provides a torque control method for an electric vehicle, comprising:

[0006] Obtain driving information and actual motor speed of the electric vehicle in the current cycle, as well as the target wheel-side required torque in the previous cycle;

[0007] Calculate the initial wheel side required torque of the current cycle according to the driving information of the current cycle;

[0008] The target wheel-side required torque of the previous cycle and the actual motor speed of the current cycle are input into the state observer to obtain the motor observed speed of the current cycle;

[0009] The wheel compensation torque of the current cycle is calculated according to the motor observed speed and the motor actual speed of the current cycle;

[0010] The initial wheel demand torque of the current cycle is compensated by using the wheel compensation torque of the current cycle to obtain the target wheel demand torque of the current cycle, and the electric vehicle is torque controlled based on the target wheel demand torque of the current cycle.

[0011] In a possible implementation, the torque control of the electric vehicle based on the target wheel-side demand torque of the current cycle includes:

[0012] The target wheel-side demand torque of the current cycle is converted into a speed ratio to obtain the shaft-side demand torque of the current cycle, and the electric vehicle is torque controlled by the shaft-side demand torque of the current cycle.

[0013] In a possible implementation, the driving information includes vehicle speed, accelerator pedal opening, and driving mode; and calculating the initial wheel side required torque of the current cycle according to the driving information of the current cycle includes:

[0014] An initial wheel side demand torque corresponding to the vehicle speed, accelerator pedal opening and driving mode of the current cycle is determined according to the map of the electric vehicle.

[0015] In a possible implementation, the calculating of the wheel compensation torque of the current cycle according to the motor observed speed and the motor actual speed of the current cycle includes:

[0016] Calculate the difference between the motor observed speed and the motor actual speed in the current cycle;

[0017] The difference is input into the incremental PID controller to obtain the wheel compensation torque of the current cycle.

[0018] In a possible implementation, inputting the difference into an incremental PID controller to obtain the wheel compensation torque of the current cycle includes:

[0019] Inputting the difference into the incremental PID controller to obtain a first torque value;

[0020] The first torque value is corrected by using a correction coefficient to obtain the wheel side compensation torque of the current cycle.

[0021] In a second aspect, the present application provides a torque control device for an electric vehicle, comprising:

[0022] A data acquisition module is used to obtain driving information and actual motor speed of the electric vehicle in the current cycle, as well as the target wheel-side required torque in the previous cycle;

[0023] An initial required torque calculation module, used to calculate the initial wheel side required torque of the current cycle according to the driving information of the current cycle;

[0024] The motor observed speed calculation module is used to input the target wheel side required torque of the previous cycle and the actual motor speed of the current cycle into the state observer to obtain the motor observed speed of the current cycle;

[0025] A compensation torque calculation module is used to calculate the wheel side compensation torque of the current cycle according to the motor observed speed and the motor actual speed of the current cycle;

[0026] The torque compensation control module is used to compensate the initial wheel demand torque of the current cycle with the wheel compensation torque of the current cycle to obtain the target wheel demand torque of the current cycle, and perform torque control on the electric vehicle based on the target wheel demand torque of the current cycle.

[0027] In a possible implementation, the torque compensation control module is specifically used to:

[0028] The target wheel-side demand torque of the current cycle is converted into a speed ratio to obtain the shaft-side demand torque of the current cycle, and the electric vehicle is torque controlled by the shaft-side demand torque of the current cycle.

[0029] In a possible implementation, the driving information includes vehicle speed, accelerator pedal opening, and driving mode; the initial required torque calculation module is specifically used for:

[0030] An initial wheel side demand torque corresponding to the vehicle speed, accelerator pedal opening and driving mode of the current cycle is determined according to the map of the electric vehicle.

[0031] In a possible implementation, the compensation torque calculation module includes:

[0032] A difference calculation unit, used to calculate the difference between the motor observed speed and the motor actual speed in the current cycle;

[0033] The wheel compensation torque calculation unit is used to input the difference into the incremental PID controller to obtain the wheel compensation torque of the current cycle.

[0034] In a possible implementation, the wheel side compensation torque calculation unit is specifically used to:

[0035] Inputting the difference into the incremental PID controller to obtain a first torque value;

[0036] The first torque value is corrected by using a correction coefficient to obtain the wheel side compensation torque of the current cycle.

[0037] In a third aspect, the present application provides a terminal comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the method described in the possible implementation manner of the first aspect are implemented.

[0038] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method described in any possible implementation of the first aspect above are implemented.

[0039] In a fifth aspect, an embodiment of the present application provides an electric vehicle, which includes the terminal described in the third aspect.

[0040] The embodiment of the present application provides a torque control method and related device for an electric vehicle, the method calculates the initial wheel-side demand torque of the current cycle based on the driving information of the current cycle; inputs the target wheel-side demand torque of the previous cycle and the actual motor speed of the current cycle into a state observer to obtain the observed motor speed of the current cycle; calculates the wheel-side compensation torque of the current cycle based on the observed motor speed of the current cycle and the actual motor speed; uses the wheel-side compensation torque of the current cycle to compensate the initial wheel-side demand torque of the current cycle to obtain the target wheel-side demand torque of the current cycle, and performs torque control on the electric vehicle based on the target wheel-side demand torque of the current cycle. Through the above scheme, the present embodiment can determine the observed motor speed of the current cycle through the state observer, thereby compensating the torque according to the observed motor speed and the actual motor speed, so as to achieve effective control within the full speed range, thereby reducing speed fluctuations and torque shocks. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0042] Figure 1 This is an application scenario diagram of the torque control method for an electric vehicle provided in an embodiment of the present application;

[0043] Figure 2 is a flow chart of the implementation of the torque control method of the electric vehicle provided in the embodiment of the present application;

[0044] Figure 3 is a flow chart of active damping closed-loop control provided by an embodiment of the present application;

[0045] Figure 4 is a schematic structural diagram of a torque control device for an electric vehicle provided in an embodiment of the present application;

[0046] Figure 5 It is a schematic diagram of a terminal provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0048] In order to make the purpose, technical solutions and advantages of the present application clearer, specific embodiments will be described below in conjunction with the accompanying drawings.

[0049] Figure 1 This is an application scenario diagram of the torque control method for an electric vehicle provided in an embodiment of the present application. Figure 1 As shown, the electric vehicle includes a vehicle controller 10, a front axle MCU 20, a rear axle MCU 21, a front axle motor 30 and a rear axle motor 31. The vehicle controller is connected to the front axle MCU and the rear axle MCU respectively, the front axle MCU is used to control the front axle motor 30, and the rear axle MCU is used to control the rear axle motor 31.

[0050] The execution subject of this embodiment is the vehicle controller.

[0051] Figure 2 The implementation process of the torque control method of the electric vehicle provided in the embodiment of the present application is described in detail as follows:

[0052] S101: Acquire driving information and actual motor speed of the electric vehicle in a current cycle, and target wheel-side required torque in a previous cycle.

[0053] In this embodiment, the vehicle controller obtains driving information of the electric vehicle, and the driving information may include driving mode, accelerator pedal opening, brake pedal opening, vehicle speed, etc. The driving mode may include economic mode eco, comfort mode comfort, sports mode sport, and power mode powerBoost.

[0054] In this embodiment, Figure 1 Taking the electric vehicle structure in as an example, the motor includes a front axle motor and a rear axle motor, the actual motor speed includes the actual speed of the front axle motor and the actual speed of the rear axle motor, and the target wheel-side demand torque includes the target wheel-side demand torque of the front axle and the target wheel-side demand torque of the rear axle.

[0055] S102: Calculate the initial wheel-side required torque of the current cycle according to the driving information of the current cycle.

[0056] In this embodiment, the vehicle controller calculates the initial wheel side required torque of the wheels corresponding to the front axle motor according to the pedal opening, driving mode, vehicle speed and other driving information corresponding to the front axle motor, and calculates the initial wheel side required torque of the wheels corresponding to the rear axle motor according to the pedal opening, driving mode, vehicle speed and other driving information corresponding to the rear axle motor. The pedal opening may include the accelerator pedal opening and the brake pedal opening.

[0057] In this embodiment, if Figure 3 As shown, Figure 3 A schematic diagram of active damping closed-loop control of an electric vehicle provided by this embodiment is shown.

[0058] like Figure 3 As shown, this embodiment can determine the wheel-side demand torque of the current cycle according to driving information such as driving mode, accelerator pedal opening, brake pedal opening and vehicle speed, and use it as the initial wheel-side demand torque T1.

[0059] In a possible implementation, the above S102 includes:

[0060] The initial wheel side required torque T1 corresponding to the vehicle speed, accelerator pedal opening and driving mode of the current cycle is determined according to the map of the electric vehicle.

[0061] In this embodiment, the spectrum diagram is a diagram formed by discretizing a multi-dimensional characteristic surface including vehicle speed, pedal opening, driving mode and initial wheel side required torque obtained by whole vehicle calibration of the electric vehicle.

[0062] Specifically, the map may include a driving torque map and a braking torque map. The driving torque map is a map formed by discretizing a multi-dimensional characteristic surface including vehicle speed, accelerator pedal opening, driving mode and initial wheel-side demand torque obtained by whole vehicle calibration of the electric vehicle, and the braking torque map is a map formed by discretizing a multi-dimensional characteristic surface including vehicle speed, brake pedal opening, driving mode and initial wheel-side demand torque obtained by whole vehicle calibration of the electric vehicle.

[0063] The wheel-side demand torque includes the driving wheel-side demand torque and the braking wheel-side demand torque. The vehicle controller can match the corresponding wheel-side driving demand torque from the driving torque map according to the accelerator pedal opening, vehicle speed, and driving mode, and can also match the corresponding wheel-side braking demand torque from the braking torque map according to the brake pedal opening, vehicle speed, and driving mode, and then determine the final initial wheel-side demand torque based on the wheel-side driving demand torque and the wheel-side braking demand torque.

[0064] The map can also be a discretized multi-dimensional characteristic surface including vehicle speed, accelerator pedal opening, brake pedal opening, driving mode and initial wheel-side demand torque obtained by vehicle calibration of the electric vehicle. The vehicle controller can directly match the corresponding initial wheel-side demand torque from the map according to the accelerator pedal opening, brake pedal opening, vehicle speed and driving mode.

[0065] S103: Input the target wheel-side required torque of the previous cycle and the actual motor speed of the current cycle into the state observer to obtain the observed motor speed of the current cycle.

[0066] Under the operating conditions of low-speed starting, emergency braking / emergency starting and frequent switching between electric power generation modes, pure electric vehicles will cause resonance between the cogging torque and the bracket, so the rate of change of the motor speed is large. Under high-speed conditions, the rate of change of the motor speed is very fast, so the controller cannot effectively control the vibration by adjusting the torque according to the rate of change of the speed.

[0067] like Figure 3 As shown, in order to avoid the above situation, the present embodiment adopts a state observer, which is a type of dynamic system that obtains estimated values ​​of state variables based on the measured values ​​of the system's external variables (input variables and output variables). It solves the problem that the state cannot be directly measured through reconstruction. The present embodiment is based on a closed-loop control strategy of the state observer, which can estimate the motor observed speed n2 of the current cycle based on the target wheel-side demand torque T2 of the previous cycle and the motor actual speed n1 of the current cycle, and calculate the difference between the motor observed speed n2 of the current cycle and the motor actual speed n1, so as to perform torque compensation based on the difference, thereby avoiding the problem of poor active damping control effect due to the inability to effectively identify changes in the rate of change under high-speed conditions.

[0068] Specifically, if the electric vehicle is driven by dual motors, the vehicle controller inputs the target wheel-side demand torque of the front axle motor in the previous cycle and the actual motor speed of the current cycle into the state observer to obtain the motor observed speed of the front axle motor in the current cycle, and inputs the target wheel-side demand torque of the rear axle motor in the previous cycle and the actual motor speed of the current cycle into the state observer to obtain the motor observed speed of the rear axle motor in the current cycle.

[0069] S104: Calculate the wheel compensation torque of the current cycle according to the motor observed speed and the motor actual speed of the current cycle.

[0070] Specifically, the torque required to compensate the initial wheel-side demand torque is determined by the difference between the motor observed speed and the motor actual speed in the current cycle.

[0071] In a possible implementation, S104 includes:

[0072] S201: Calculate the difference between the motor observed speed and the motor actual speed in the current cycle;

[0073] S202: Input the difference into an incremental PID controller to obtain the wheel compensation torque of the current cycle.

[0074] The vehicle controller can input the difference between the observed motor speed and the actual motor speed into the incremental PID controller to obtain the wheel side compensation torque ΔT.

[0075] In a possible implementation manner, the specific implementation process of S202 includes:

[0076] Inputting the difference into the incremental PID controller to obtain a first torque value;

[0077] The first torque value is corrected by using a correction coefficient to obtain the wheel side compensation torque of the current cycle.

[0078] In this embodiment, in order to ensure the accuracy and calculation efficiency of the wheel compensation torque, after the first torque value is calculated by using the incremental PID controller, the first torque value can also be corrected according to actual conditions. Specifically, the correction coefficient is a parameter determined in the early stage through actual vehicle testing.

[0079] S105: using the wheel compensation torque of the current cycle to compensate the initial wheel demand torque of the current cycle to obtain the target wheel demand torque of the current cycle, and performing torque control on the electric vehicle based on the target wheel demand torque of the current cycle.

[0080] In this embodiment, if Figure 3 As shown, after obtaining the wheel compensation torque ΔT, the vehicle controller adds the initial wheel torque T1 of the current cycle and the compensation torque ΔT to obtain the target wheel demand torque T2 of the current cycle.

[0081] In a possible implementation, the above S105 includes:

[0082] The target wheel-side demand torque of the current cycle is converted into a speed ratio to obtain the shaft-side demand torque of the current cycle, and the electric vehicle is torque controlled by the shaft-side demand torque of the current cycle.

[0083] Specifically, the speed ratio refers to the gear ratio of the final reducer in the automobile drive axle, which is equal to the ratio of the angular velocity of the drive shaft to the angular velocity of the axle half shaft, and is also equal to the ratio of their rotational speeds.

[0084] Reference Figure 1 and Figure 3, this embodiment calculates the wheel compensation torque of the current cycle corresponding to the front axle motor according to the motor observed speed and the actual speed of the motor of the current cycle corresponding to the front axle motor, and calculates the wheel compensation torque of the current cycle corresponding to the rear axle motor according to the motor observed speed and the actual speed of the motor of the current cycle corresponding to the rear axle motor, and then uses the wheel compensation torque of the current cycle of the front axle motor to compensate the initial wheel demand torque of the current cycle corresponding to the front axle to obtain the target wheel demand torque of the current cycle corresponding to the front axle. The wheel compensation torque of the current cycle of the rear axle is used to compensate the initial wheel demand torque of the current cycle corresponding to the rear axle to obtain the target wheel demand torque of the current cycle corresponding to the rear axle. After obtaining the target wheel demand torque of the front and rear axles, the vehicle controller can divide the target wheel demand torque T2 of the front axle by the speed ratio to obtain the shaft demand torque T3 of the current cycle corresponding to the front axle, and send the shaft demand torque of the current cycle corresponding to the front axle to the front axle MCU, so that the front axle MCU directly outputs the torque command to the shaft end of the front axle motor. The vehicle controller can also divide the target wheel-side demand torque T2 of the rear axle by the speed ratio to obtain the axle-side demand torque T3 of the rear axle corresponding to the current cycle, and send the axle-side demand torque of the rear axle corresponding to the current cycle to the rear axle MCU, so that the rear axle MCU can directly output the torque command to the rear axle motor shaft end to avoid communication delay problems.

[0085] In addition, this embodiment can also adaptively change the torque control method according to the different motor drive architectures of the electric vehicle.

[0086] Specifically, if the electric vehicle is a single-motor driven vehicle, the actual motor speed is the actual motor speed of the single motor. The vehicle controller calculates the corresponding initial wheel-side demand torque based on the actual motor speed, driving mode, vehicle speed and other driving information corresponding to the single motor; then the target wheel-side demand torque of the previous cycle corresponding to the single motor and the actual motor speed of the current cycle are input into the state observer to obtain the motor observed speed of the current cycle of the single motor. The wheel-side compensation torque of the single motor is calculated based on the motor observed speed and the actual motor speed of the current cycle, and the wheel-side compensation torque is used to compensate the initial wheel-side demand torque of the single motor to obtain the target wheel-side demand torque corresponding to the single motor, and the target wheel-side demand torque is converted into the shaft-side demand torque, and the shaft-side demand torque is sent to the single-motor MCU to control the single drive motor to drive the wheels of the vehicle according to the shaft-side demand torque.

[0087] If the electric vehicle is a four-wheel drive vehicle, that is, each wheel corresponds to a drive motor, then the actual motor speed includes the actual speed of the front axle left wheel motor, the actual speed of the front axle right wheel motor, the actual speed of the rear axle left wheel motor, and the actual speed of the rear axle right wheel motor. For any drive motor, the vehicle controller calculates the initial wheel side demand torque of the wheel corresponding to the motor according to the actual motor speed, driving mode, pedal opening, vehicle speed and other driving information corresponding to the drive motor, and then inputs the target wheel side demand torque of the drive motor in the previous cycle and the actual motor speed of the current cycle into the state observer to obtain the motor observed speed of the drive motor in the current cycle, calculates the difference between the motor observed speed and the actual motor speed of the drive motor in the current cycle, and inputs the difference into the incremental PID controller to obtain the first torque value of the drive motor in the current cycle, and then uses the correction coefficient to correct the first torque value to obtain the wheel side compensation torque of the drive motor in the current cycle. The wheel-side compensation torque of the current cycle of the drive motor is used to compensate the initial wheel-side demand torque of the current cycle to obtain the target wheel-side demand torque of the drive motor in the current cycle, and the speed ratio of the target wheel-side demand torque is converted to obtain the shaft-side demand torque of the drive motor in the current cycle. Finally, the shaft-side demand torque is sent to the MCU corresponding to the drive motor, so that the MCU directly sends a torque command to the shaft end of the drive motor to control the corresponding drive motor torque.

[0088] It can be seen from the above embodiments that this embodiment calculates the initial wheel-side demand torque of the current cycle based on the driving information of the current cycle; inputs the target wheel-side demand torque of the previous cycle and the actual motor speed of the current cycle into the state observer to obtain the observed motor speed of the current cycle; calculates the wheel-side compensation torque of the current cycle based on the observed motor speed of the current cycle and the actual motor speed; uses the wheel-side compensation torque of the current cycle to compensate the initial wheel-side demand torque of the current cycle to obtain the target wheel-side demand torque of the current cycle, and performs torque control on the electric vehicle based on the target wheel-side demand torque of the current cycle. Through the above scheme, this embodiment can determine the observed motor speed of the current cycle through the state observer, thereby compensating the torque according to the observed motor speed and the actual motor speed, reducing speed fluctuations and torque shocks, suppressing the torque ripple jitter amplitude, reducing the impact of the entire vehicle, and improving driving comfort without increasing hardware costs, and the practical effect is obvious.

[0089] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0090] The following is an embodiment of the device of the present application. For details not described in detail, please refer to the corresponding method embodiment described above.

[0091] Figure 4 The structure diagram of the torque control device of the electric vehicle provided by the embodiment of the present application is shown. For the convenience of explanation, only the part related to the embodiment of the present application is shown, which is described in detail as follows:

[0092] like Figure 4 As shown, the torque control device 300 of the electric vehicle includes:

[0093] The data acquisition module 110 is used to acquire the driving information and the actual motor speed of the electric vehicle in the current cycle, and the target wheel side required torque in the previous cycle;

[0094] The initial required torque calculation module 120 is used to calculate the initial wheel side required torque of the current cycle according to the driving information of the current cycle;

[0095] The motor observed speed calculation module 130 is used to input the target wheel side required torque of the previous cycle and the actual motor speed of the current cycle into the state observer to obtain the motor observed speed of the current cycle;

[0096] The compensation torque calculation module 140 is used to calculate the wheel side compensation torque of the current cycle according to the motor observed speed and the motor actual speed of the current cycle;

[0097] The torque compensation control module 150 is used to compensate the initial wheel demand torque of the current cycle with the wheel compensation torque of the current cycle, obtain the target wheel demand torque of the current cycle, and perform torque control on the electric vehicle based on the target wheel demand torque of the current cycle.

[0098] It can be seen from the above embodiments that this embodiment calculates the initial wheel-side demand torque of the current cycle based on the driving information of the current cycle; inputs the target wheel-side demand torque of the previous cycle and the actual motor speed of the current cycle into the state observer to obtain the observed motor speed of the current cycle; calculates the wheel-side compensation torque of the current cycle based on the observed motor speed of the current cycle and the actual motor speed; uses the wheel-side compensation torque of the current cycle to compensate the initial wheel-side demand torque of the current cycle to obtain the target wheel-side demand torque of the current cycle, and performs torque control on the electric vehicle based on the target wheel-side demand torque of the current cycle. Through the above scheme, this embodiment can determine the observed motor speed of the current cycle through the state observer, thereby compensating the torque according to the observed motor speed and the actual motor speed, reducing speed fluctuations and torque shocks, suppressing the torque ripple jitter amplitude, reducing the impact of the entire vehicle, and improving driving comfort without increasing hardware costs, and the practical effect is obvious.

[0099] In a possible implementation, the torque compensation control module 150 is specifically used to:

[0100] The target wheel-side demand torque of the current cycle is converted into a speed ratio to obtain the shaft-side demand torque of the current cycle, and the electric vehicle is torque controlled by the shaft-side demand torque of the current cycle.

[0101] In a possible implementation, the driving information includes vehicle speed, accelerator pedal opening, and driving mode; the initial required torque calculation module 120 is specifically used for:

[0102] An initial wheel side demand torque corresponding to the vehicle speed, accelerator pedal opening and driving mode of the current cycle is determined according to the map of the electric vehicle.

[0103] In a possible implementation, the compensation torque calculation module 140 includes:

[0104] A difference calculation unit, used to calculate the difference between the motor observed speed and the motor actual speed in the current cycle;

[0105] The wheel compensation torque calculation unit is used to input the difference into the incremental PID controller to obtain the wheel compensation torque of the current cycle.

[0106] In a possible implementation, the wheel side compensation torque calculation unit is specifically used to:

[0107] Inputting the difference into the incremental PID controller to obtain a first torque value;

[0108] The first torque value is corrected by using a correction coefficient to obtain the wheel side compensation torque of the current cycle.

[0109] The present application also provides a computer program product having a program code, which executes the steps of any of the above-mentioned torque control method embodiments of the electric vehicle when the program code is run in a corresponding processor, controller, computing device or terminal, such as Figure 2 Steps 101 to 105 shown. Those skilled in the art will appreciate that the method and the device of the present application embodiment can be implemented in various forms of hardware, software, firmware, a dedicated processor or a combination thereof. The dedicated processor may include an application specific integrated circuit (ASIC), a reduced instruction set computer (RISC) and / or a field programmable gate array (FPGA). The proposed method and device are preferably implemented as a combination of hardware and software. The software is preferably installed on a program storage device as an application. It is typically based on a machine with a computer platform having hardware, such as one or more central processing units (CPUs), random access memories (RAMs) and one or more input / output (I / O) interfaces. An operating system is typically also installed on the computer platform. The various processes and functions described herein may be part of an application, or a part thereof may be executed by an operating system.

[0110] Figure 5 is a schematic diagram of a terminal provided in an embodiment of the present application. Figure 5 As shown, the terminal 5 of this embodiment includes: a processor 50, a memory 51, and a computer program 52 stored in the memory 51 and executable on the processor 50. When the processor 50 executes the torque control method of the electric vehicle, the steps in the above-mentioned computer program 52 method embodiments are implemented, for example Figure 2 Alternatively, when the processor 50 executes the computer program 52, the functions of each module / unit in the above-mentioned device embodiments are realized, for example, Figure 4 Functionality of modules / units 110 to 150 is shown.

[0111] Exemplarily, the computer program 52 may be divided into one or more modules / units, which are stored in the memory 51 and executed by the processor 50 to complete / implement the solution provided by the present application. The one or more modules / units may be a series of computer program instruction segments that can complete specific functions, and the instruction segments are used to describe the execution process of the computer program 52 in the terminal 5. For example, the computer program 52 may be divided into Figure 4 Modules / units 110 to 150 are shown.

[0112] The terminal 5 may include, but is not limited to, a processor 50 and a memory 51. Those skilled in the art will appreciate that Figure 5 It is only an example of terminal 5 and does not constitute a limitation on terminal 5. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the terminal may also include input and output devices, network access devices, buses, etc.

[0113] The processor 50 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0114] The memory 51 may be an internal storage unit of the terminal 5, such as a hard disk or memory of the terminal 5. The memory 51 may also be an external storage device of the terminal 5, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the terminal 5. Further, the memory 51 may also include both an internal storage unit of the terminal 5 and an external storage device. The memory 51 is used to store the computer program and other programs and data required by the terminal. The memory 51 may also be used to temporarily store data that has been output or is to be output.

[0115] This embodiment also provides an electric vehicle, comprising the above-mentioned terminal 5 .

[0116] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0117] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0118] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0119] In the embodiments provided in the present application, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0120] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0121] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0122] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the torque control method embodiments of each electric vehicle can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device that can carry the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practices in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practices, computer-readable media does not include electrical carrier signals and telecommunication signals.

[0123] In addition, the embodiments shown in the drawings of the present application or the features of the various embodiments mentioned in this specification are not necessarily understood as independent embodiments. Instead, each feature described in one example of an embodiment can be combined with one or more other desired features from other embodiments to produce other embodiments not described in words or with reference to the drawings.

[0124] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A torque control method for an electric vehicle, characterized in that: include: Obtain driving information and actual motor speed of the electric vehicle in the current cycle, as well as the target wheel-side required torque in the previous cycle; Calculate the initial wheel side required torque of the current cycle according to the driving information of the current cycle; The target wheel-side required torque of the previous cycle and the actual motor speed of the current cycle are input into the state observer to obtain the motor observed speed of the current cycle; The wheel compensation torque of the current cycle is calculated according to the motor observed speed and the motor actual speed of the current cycle; Using the wheel compensation torque of the current cycle to compensate the initial wheel demand torque of the current cycle to obtain the target wheel demand torque of the current cycle, and performing torque control on the electric vehicle based on the target wheel demand torque of the current cycle; The driving information includes vehicle speed, accelerator pedal opening and driving mode; the initial wheel side required torque of the current cycle is calculated according to the driving information of the current cycle, including: Determining an initial wheel side required torque corresponding to the vehicle speed, accelerator pedal opening and driving mode of the current cycle according to the map of the electric vehicle; The step of calculating the wheel compensation torque of the current cycle according to the motor observed speed and the motor actual speed of the current cycle includes: Calculate the difference between the motor observed speed and the motor actual speed in the current cycle; The difference is input into the incremental PID controller to obtain the wheel compensation torque of the current cycle.

2. The torque control method of an electric vehicle according to claim 1, characterized in that: The torque control of the electric vehicle based on the target wheel side demand torque of the current cycle includes: The target wheel-side demand torque of the current cycle is converted into a speed ratio to obtain the shaft-side demand torque of the current cycle, and the electric vehicle is torque controlled by the shaft-side demand torque of the current cycle.

3. The torque control method of an electric vehicle according to claim 1, characterized in that: The step of inputting the difference into an incremental PID controller to obtain the wheel compensation torque of the current cycle includes: Inputting the difference into the incremental PID controller to obtain a first torque value; The first torque value is corrected by using a correction coefficient to obtain the wheel side compensation torque of the current cycle.

4. A torque control device for an electric vehicle, characterized in that: include: A data acquisition module is used to obtain driving information and actual motor speed of the electric vehicle in the current cycle, as well as the target wheel-side required torque in the previous cycle; An initial required torque calculation module, used to calculate the initial wheel side required torque of the current cycle according to the driving information of the current cycle; The motor observed speed calculation module is used to input the target wheel side required torque of the previous cycle and the actual motor speed of the current cycle into the state observer to obtain the motor observed speed of the current cycle; A compensation torque calculation module is used to calculate the wheel side compensation torque of the current cycle according to the motor observed speed and the motor actual speed of the current cycle; A torque compensation control module, used to compensate the initial wheel side demand torque of the current cycle with the wheel side compensation torque of the current cycle, obtain the target wheel side demand torque of the current cycle, and perform torque control on the electric vehicle based on the target wheel side demand torque of the current cycle; The driving information includes vehicle speed, accelerator pedal opening and driving mode; the initial required torque calculation module is specifically used for: Determining an initial wheel side required torque corresponding to the vehicle speed, accelerator pedal opening and driving mode of the current cycle according to the map of the electric vehicle; The compensation torque calculation module is specifically used for: Calculate the difference between the motor observed speed and the motor actual speed in the current cycle; The difference is input into the incremental PID controller to obtain the wheel compensation torque of the current cycle.

5. The torque control device for an electric vehicle as claimed in claim 4, characterized in that: The torque compensation control module is specifically used for: The target wheel-side demand torque of the current cycle is converted into a speed ratio to obtain the shaft-side demand torque of the current cycle, and the electric vehicle is torque controlled by the shaft-side demand torque of the current cycle.

6. A terminal comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the torque control method for an electric vehicle as described in any one of claims 1 to 3 are implemented.

7. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the torque control method for an electric vehicle as described in any one of claims 1 to 3 are implemented.

8. An electric vehicle, characterized in that: Comprising the terminal as claimed in claim 6.

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