Motor output torque control method, device and equipment and readable storage medium

Abstract

The invention discloses a motor output torque control method, device and equipment and a readable storage medium. The method comprises the steps that the slip rate of each wheel is obtained according to the filtering speed of the vehicle and the filtering wheel speed of each wheel; obtaining the slip rate error of each wheel based on the upper and lower limits of the target slip rate and the slip rate of each wheel; based on the slip rate error of each wheel, obtaining a first additional torque of a motor corresponding to each wheel through a proportional-integral algorithm; limiting the first additional torque of each motor based on the motor capability to obtain a second additional torque of each motor; and optimizing the second additional torque of each motor to obtain a third additional torque of each motor. According to the control method and device, based on control over the output torque of all the driving motors, sliding and instability in the vehicle movement process are restrained, and meanwhile the smoothness of the output torque of the motors is guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle control, in particular to a motor output torque control method, device, equipment and computer readable storage medium. BACKGROUND

[0002] Each wheel of the multi-wheel independently driven vehicle is driven by an independent motor, that is, each driving wheel is an independent actuator, and torque can be independently applied. How to control the torque of each motor to suppress wheel slip and vehicle instability is a technical problem to be solved. SUMMARY

[0003] To solve the above technical problems, the present application provides a motor output torque control method, device, equipment and computer readable storage medium.

[0004] In a first aspect, an embodiment of the present application provides a motor output torque control method, which comprises: obtaining the slip rate of each wheel according to the filtered vehicle speed of the vehicle and the filtered wheel speed of each wheel; obtaining the slip rate error of each wheel based on the upper and lower limits of the target slip rate and the slip rate of each wheel; obtaining the first additional torque of the motor corresponding to each wheel through a proportional integral algorithm based on the slip rate error of each wheel; limiting the first additional torque of each motor based on the motor capacity to obtain the second additional torque of each motor; optimizing the second additional torque of each motor to obtain the third additional torque of each motor, so that after superimposing the third additional torque of each motor on the current output torque of each motor, the yaw moment of the vehicle tends to a preset value, and the total output torque obtained by superimposing the third additional torque of each motor on the current output torque of each motor is not greater than the driving request torque.

[0005] In combination with the first aspect, in an implementation mode, the optimization of the second additional torque of each motor to obtain the third additional torque of each motor comprises: solving x to make the following function satisfy to obtain the third additional torque of each motor:

[0006]

[0007]

[0008] Wherein, x is a column vector composed of the third additional torque of multiple motors, △T is a column vector composed of the second additional torque of multiple motors, Tcur is a column vector composed of the current output torque of multiple motors, λ1 and λ2 are weight coefficients, α is a constant vector, T driver Request torque for driving.

[0009] In combination with the first aspect, in one embodiment, limiting the first additional torque of each motor based on motor capability to obtain the second additional torque of each motor includes: For motor i, according to the current output torque T of motor i i，cur , the upper limit value T of the output torque of motor i i，max and the lower limit value T of the output torque of motor i i，min Determine the first upper limit value T of the additional torque i，max -T i，cur and the first lower limit value T of the additional torque i，min -T i，cur If the first additional torque of motor i is greater than the first upper limit, the first upper limit is used as the second additional torque of motor i; if the first additional torque of motor i is less than the first lower limit, the first lower limit is used as the second additional torque of motor i; if the first additional torque of motor i is between the first lower limit and the first upper limit, the first additional torque of motor i is used as the second additional torque of motor i; And / or, for motor i, the maximum value of the torque response of motor i is used as the second upper limit value, and the minimum value of the torque response of motor i is used as the second lower limit value. If the first additional torque of motor i is greater than the second upper limit value, the second upper limit value is used as the second additional torque of motor i; if the first additional torque of motor i is less than the second lower limit value, the second lower limit value is used as the second additional torque of motor i; if the first additional torque of motor i is between the second lower limit value and the second upper limit value, the first additional torque of motor i is used as the second additional torque of motor i.

[0010] In conjunction with the first aspect, in one embodiment, obtaining the first additional torque of the motor corresponding to each wheel by a proportional-integral algorithm based on the slip rate error of each wheel includes: For wheel i, the slip rate error of wheel i is substituted into the proportional integral algorithm formula to obtain the first additional torque △T of motor i corresponding to wheel i i , the proportional integral algorithm formula is as follows:

[0011] Among them, K p is the parameter obtained through prior information, K i is the calibration parameter, e i (t) is the slip rate error of wheel i at time t.

[0012] In combination with the first aspect, in an implementation, the obtaining the slip error of each wheel based on the upper and lower limits of the target slip ratio and the slip ratio of each wheel comprises: For each wheel, when the slip ratio of the wheel is less than the lower limit of the target slip ratio, taking the difference between the lower limit of the target slip ratio and the slip ratio of the wheel as the slip error of the wheel; when the slip ratio of the wheel is greater than the upper limit of the target slip ratio, taking the difference between the upper limit of the target slip ratio and the slip ratio of the wheel as the slip error of the wheel; when the slip ratio of the wheel is between the upper and lower limits of the target slip ratio, setting the slip error of the wheel to zero.

[0013] In combination with the first aspect, in an implementation, the obtaining the slip ratio of each wheel based on the filtered vehicle speed of the vehicle and the filtered wheel speed of each wheel comprises: For wheel i, substituting the filtered vehicle speed of the vehicle and the filtered wheel speed of wheel i into a slip ratio calculation formula to obtain the slip ratio of the wheel The slip ratio calculation formula is as follows:

[0014] Wherein, is the effective rolling radius of wheel i, is the filtered vehicle speed of the vehicle, is the filtered wheel speed of wheel i.

[0015] In combination with the first aspect, in an implementation, after the optimizing the second additional torque of each motor to obtain the third additional torque of each motor, the method further comprises: For each motor, generating a torque request based on the third additional torque of the motor and the current output torque of the motor, and sending the torque request to the motor.

[0016] The second aspect, the embodiments of the present application provide a motor output torque control device, the motor output torque control device comprises: A first calculation module is configured to obtain the slip ratio of each wheel based on the filtered vehicle speed of the vehicle and the filtered wheel speed of each wheel; A second calculation module is configured to obtain the slip error of each wheel based on the upper and lower limits of the target slip ratio and the slip ratio of each wheel; A third calculation module is configured to obtain the first additional torque of the motor corresponding to each wheel based on the slip error of each wheel through a proportional integral algorithm; A fourth calculation module is configured to limit the first additional torque of each motor based on the motor capability to obtain the second additional torque of each motor; The optimization module is configured to optimize the second additional torque of each motor to obtain a third additional torque of each motor, so that after the third additional torque of each motor is superimposed on a current output torque of each motor, a yaw moment of the vehicle tends to a preset value, and a total output torque obtained by superimposing the third additional torque of each motor on the current output torque of each motor is not greater than the driving request torque.

[0017] In a third aspect, an embodiment of the present application provides a motor output torque control device, which comprises a processor, a memory, and a motor output torque control program stored in the memory and executable by the processor, wherein when the motor output torque control program is executed by the processor, the steps of the motor output torque control method according to the first aspect are implemented.

[0018] In a fourth aspect, an embodiment of the present application provides a computer readable storage medium, which stores a motor output torque control program, wherein when the motor output torque control program is executed by a processor, the steps of the motor output torque control method according to the first aspect are implemented.

[0019] The technical scheme provided by the embodiment of the present application has the following beneficial effects: In the embodiment of the present application, the slip rate of each wheel is obtained according to the filtered vehicle speed of the vehicle and the filtered wheel speed of each wheel; the slip rate error of each wheel is obtained based on the upper and lower limits of the target slip rate and the slip rate of each wheel; the first additional torque of the motor corresponding to each wheel is obtained through a proportional integral algorithm based on the slip rate error of each wheel; the second additional torque of each motor is limited based on the motor capacity to obtain the third additional torque of each motor; the third additional torque of each motor is optimized to obtain the third additional torque of each motor, so that after the third additional torque of each motor is superimposed on the current output torque of each motor, the yaw moment of the vehicle tends to a preset value, and the total output torque obtained by superimposing the third additional torque of each motor on the current output torque of each motor is not greater than the driving request torque. Through the embodiment of the present application, the slip and instability in the motion process of the vehicle are inhibited based on the control of the output torque of each drive motor, while the smoothness of the motor output torque is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The flowchart of an embodiment of the motor output torque control method of the present application is shown in the figure. Figure 2 The function module schematic diagram of an embodiment of the motor output torque control device of the present application is shown in the figure. Figure 3 The hardware structure schematic diagram of the motor output torque control device involved in the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0022] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0023] In a first aspect, an embodiment of the present application provides a method for controlling motor output torque.

[0024] In one embodiment, referring to Figure 1 , Figure 1 This is a flow chart of an embodiment of the motor output torque control method of the present application. Figure 1 As shown, the motor output torque control method includes: Step S10, obtaining the slip rate of each wheel based on the filtered vehicle speed and the filtered wheel speed of each wheel; In this embodiment, the wheel speed of each wheel and the vehicle speed have slight jitters, so the input signal is first smoothed to remove signal interference.

[0025] The wheel speed of each wheel is filtered as follows:

[0026]

[0027] Among them, among them, is the filtered wheel speed at the initial moment, is the sampling wheel speed at the initial moment, is the filtered wheel speed at time t, is the filtered wheel speed at time t-1, is the sampling wheel speed at time t. It is a calibrable wheel speed filter parameter.

[0028] The vehicle speed is filtered as follows:

[0029]

[0030] Among them, V x0 is the filtered vehicle speed at the initial moment, is the sampling speed at the initial moment, V xt is the filtered vehicle speed at time t, V x（t-1） is the filtered vehicle speed at time t-1, is the sampled vehicle speed at time t. It is a calibrable vehicle speed filter parameter.

[0031] Furthermore, in one embodiment, step S10 includes: For wheel i, substitute the vehicle's filtered speed and wheel i's filtered speed into the slip rate calculation formula to obtain the wheel slip rate: , the slip rate calculation formula is as follows:

[0032] in, is the effective rolling radius of wheel i, is the filtered speed of the vehicle, is the filtered wheel speed of wheel i.

[0033] In this embodiment, after obtaining the filtered wheel speed of each wheel and the filtered vehicle speed, the slip ratio of each wheel can be calculated by substituting them into the above slip ratio calculation formula. Taking a 6-wheel independent drive vehicle as an example, i={1,2,3,4,5,6}, where the i-th wheel represents the left front wheel, right front wheel, left middle wheel, right middle wheel, left rear wheel, and right rear wheel, respectively.

[0034] It is easy to understand that vehicle and wheel speeds are both time domain data, and slip rate is also time domain data.

[0035] Step S20, obtaining the slip rate error of each wheel based on the upper and lower limits of the target slip rate and the slip rate of each wheel; Furthermore, in one embodiment, step S20 includes: For each wheel, when the slip rate of the wheel is less than the lower limit value of the target slip rate, the difference between the lower limit value of the target slip rate and the slip rate of the wheel is used as the slip rate error of the wheel; when the slip rate of the wheel is greater than the upper limit value of the target slip rate, the difference between the upper limit value of the target slip rate and the slip rate of the wheel is used as the slip rate error of the wheel; when the slip rate of the wheel is between the upper and lower limits of the target slip rate, the slip rate error of the wheel is set to zero.

[0036] In this embodiment, the anti-skid function of the vehicle is realized by limiting the slip rate of each wheel to ensure the longitudinal driving stability of the vehicle. Set as an interval.

[0037]

[0038] in, and are lower and upper bounds of target slip ratio, respectively, and are tunable parameters.

[0039] The slip ratio error of the i-th wheel is defined as follows:

[0040] wherein, is the current slip ratio of the i-th wheel, is the current slip ratio error of the i-th wheel.

[0041] In step S30, based on the slip ratio error of each wheel, a first additional torque of the motor corresponding to each wheel is obtained through a proportional-integral algorithm. Further, in an embodiment, step S30 comprises: For the i-th wheel, the slip ratio error of the i-th wheel is substituted into the proportional-integral algorithm formula to obtain the first additional torque of the motor i corresponding to the i-th wheel i , and the proportional-integral algorithm formula is as follows:

[0042] wherein, K p is a parameter obtained through prior information, K i is a tunable parameter, and e i (t) is the slip ratio error of the i-th wheel at time t.

[0043] In this embodiment, an important goal is to suppress slip. Taking the target wheel as an example, it is considered that slip suppression is achieved when the actual slip ratio of the target wheel reaches the target slip ratio . To change the degree of slip suppression, the estimated time t tar for the actual slip ratio to reach the target slip ratio is affected, and therefore the estimated time t tar is used as prior information needed to determine .

[0044] Suppose the current speed of the vehicle is , the current acceleration of the vehicle is , and the acceleration is considered to remain unchanged within the estimated time t tar , then the speed after the estimated time t tar satisfies the following formula:

[0045] The current wheel speed of the target wheel is , the wheel speed at the last sampling time is , and the signal sampling period is , the target wheel's acceleration is considered to be If it remains unchanged during the previous sampling period, the acceleration Satisfies the following formula:

[0046] The target wheel moment of inertia is , the target wheel is considered to be subjected to the total torque If it remains unchanged during the previous sampling period, the resultant torque satisfies the following formula:

[0047] Assume that the first additional torque of the target wheel at the current moment is △T, then the total torque at the current moment is for:

[0048] Current moment acceleration for:

[0049] Assume that the rotational acceleration is at t tar The interior remains unchanged, t tar Rear target wheel speed Satisfies the following formula:

[0050] t tar Slip ratio after The calculation formula is:

[0051] Based on the slip rate error calculation formula, if we want to make t tar Slip rate error after time , then the following formula holds:

[0052]

[0053] in, is the slip rate of the target wheel at the current moment.

[0054] Combining the above 9 formulas, if we want to make t tar Slip rate error after time , then the first additional torque △T of the target wheel at the current moment should satisfy:

[0055] The slip rate error formula at the current moment is as follows:

[0056] Based on the above two formulas, K can be calculated p ,as follows:

[0057] The K p Substituting this into the proportional integral algorithm formula, it can be used to calculate the first additional torque △T of motor i corresponding to wheel i i .

[0058] Step S40, limiting the first additional torque of each motor based on the motor capacity to obtain a second additional torque of each motor; Furthermore, in one embodiment, step S40 includes: For motor i, according to the current output torque T of motor i i，cur , the upper limit value T of the output torque of motor i i，max and the lower limit value T of the output torque of motor i i，min Determine the first upper limit value T of the additional torque i，max -T i，cur and the first lower limit value T of the additional torque i，min -T i，cur If the first additional torque of motor i is greater than the first upper limit, the first upper limit is used as the second additional torque of motor i; if the first additional torque of motor i is less than the first lower limit, the first lower limit is used as the second additional torque of motor i; if the first additional torque of motor i is between the first lower limit and the first upper limit, the first additional torque of motor i is used as the second additional torque of motor i; And / or, for motor i, the maximum value of the torque response of motor i is used as the second upper limit value, and the minimum value of the torque response of motor i is used as the second lower limit value. If the first additional torque of motor i is greater than the second upper limit value, the second upper limit value is used as the second additional torque of motor i; if the first additional torque of motor i is less than the second lower limit value, the second lower limit value is used as the second additional torque of motor i; if the first additional torque of motor i is between the second lower limit value and the second upper limit value, the first additional torque of motor i is used as the second additional torque of motor i.

[0059] In this embodiment, for motor i, the first additional torque obtained is limited based on the motor capacity to obtain the second additional torque of motor i. At least one of the following two principles is followed: ① If the motor output torque does not exceed the motor's torque output capacity, the second additional torque must meet the following requirements:

[0060] The second additional torque of the motor i does not exceed the torque response range of the motor, that is, does not exceed the torque amount that can be adjusted by the motor each time. Considering the torque response capability of the motor i, the second additional torque should satisfy:

[0061] wherein, and are the maximum and minimum torque response values of the motor i respectively.

[0062] △T i is the second additional torque of the motor i.

[0063] In step S50, the second additional torque of each motor is optimized to obtain the third additional torque of each motor, so that after the third additional torque of each motor is superimposed on the current output torque of each motor, the yaw moment of the vehicle tends to the preset value, and the total output torque obtained by superimposing the third additional torque of each motor on the current output torque of each motor is not greater than the driving request torque.

[0064] Further, in an embodiment, step S50 includes: solving x that satisfies the following function to obtain the third additional torque of each motor:

[0065]

[0066]

[0067] wherein x is a column vector composed of the third additional torque of the plurality of motors, △T is a column vector composed of the second additional torque of the plurality of motors, Tcur is a column vector composed of the current output torque of the plurality of motors, λ1 and λ2 are weight coefficients, α is a constant vector, T driver is the driving request torque.

[0068] In this embodiment, for a six-wheel independent drive vehicle, in order to ensure the stability and safety of vehicle control, the second additional torque of the six motors obtained needs to be redistributed. Specifically, the redistribution should satisfy the following principles: ① The final optimized control amount tends to the obtained second additional torque.

[0069] ② The total yaw moment of the vehicle tends to =[0,0,0,0,0,0 .

[0070] ③ The optimized total torque should not be higher than the driver request torque.

[0071] Based on the principles, a multi-objective optimization task can be constructed:

[0072]

[0073]

[0074] wherein x is the transpose of the row vector of the third additional torque of the six motors to be solved. By performing the above multi-objective optimization task, the optimal x, denoted as x*, can be obtained, i.e., the third additional torque of each motor is obtained.

[0075] Further, in an embodiment, after step S50, the method further comprises: For each motor, a torque request is generated based on the third additional torque of the motor and the current output torque of the motor, and the torque request is sent to the motor.

[0076] In the embodiment, for example, the third additional torque of motor i is T i，3 , the current output torque of motor i is T i，cur , and the torque required to be output by motor i is T i，3 + T i，cur , and the corresponding torque request is generated based on the purpose and sent to the motor. Each motor is processed in this way, thereby achieving torque control of the whole vehicle.

[0077] In the embodiment, the slip ratio of each wheel is obtained according to the filtered vehicle speed and the filtered wheel speed of the vehicle; the slip ratio error of each wheel is obtained based on the upper and lower limits of the target slip ratio and the slip ratio of each wheel; the first additional torque of the motor corresponding to each wheel is obtained through a proportional integral algorithm based on the slip ratio error of each wheel; the second additional torque of each motor is obtained by limiting the first additional torque of each motor based on the motor capability; and the third additional torque of each motor is obtained by optimizing the second additional torque of each motor, so that the yaw moment of the vehicle approaches the preset value after the current output torque of each motor is superimposed with the third additional torque of each motor, and the total output torque obtained by superimposing the current output torque of each motor with the third additional torque of each motor is not greater than the driving request torque. Through the embodiment, the slip and instability in the motion process of the vehicle are inhibited based on the control of the output torque of each driving motor, while the smoothness of the output torque of the motor is ensured.

[0078] In a second aspect, the embodiment also provides a motor output torque control device.

[0079] In an embodiment, refer to Figure 2 , Figure 2 is a functional module schematic diagram of an embodiment of the motor output torque control device of the application. As Figure 2The motor output torque control device shown comprises: The first calculation module 10 is configured to obtain the slip ratio of each wheel according to the filtered vehicle speed and the filtered wheel speed of each wheel. The second calculation module 20 is configured to obtain the slip ratio error of each wheel based on the upper and lower limits of the target slip ratio and the slip ratio of each wheel. The third calculation module 30 is configured to obtain the first additional torque of the motor corresponding to each wheel based on the slip ratio error of each wheel through a proportional integral algorithm. The fourth calculation module 40 is configured to limit the first additional torque of each motor based on the motor capability to obtain the second additional torque of each motor. The optimization module 50 is configured to optimize the second additional torque of each motor to obtain the third additional torque of each motor, so that the yaw moment of the vehicle approaches the preset value after the third additional torque of each motor is superimposed on the current output torque of each motor, and the total output torque obtained by superimposing the third additional torque of each motor on the current output torque of each motor is not greater than the driving request torque.

[0080] Further, in an embodiment, the optimization module 50 is configured to: Solve x that satisfies the following function to obtain the third additional torque of each motor:

[0081]

[0082]

[0083] Wherein, x is a column vector composed of the third additional torque of the plurality of motors, △T is a column vector composed of the second additional torque of the plurality of motors, Tcur is a column vector composed of the current output torque of the plurality of motors, λ1 and λ2 are weight coefficients, α is a constant vector, T driver is the driving request torque.

[0084] Further, in an embodiment, the fourth calculation module 40 is configured to: For motor i, according to the current output torque T i，cur of motor i, the upper limit value T i，max of the output torque of motor i, and the lower limit value T i，min of the output torque of motor i, determine the first upper limit value T i，max -T i，cur of the additional torque and the first lower limit value T i，min -T i，curIf the first additional torque of the motor i is greater than the first upper limit value, the first additional torque of the motor i is taken as the second additional torque of the motor i; if the first additional torque of the motor i is less than the first lower limit value, the first additional torque of the motor i is taken as the second additional torque of the motor i; if the first additional torque of the motor i is between the first lower limit value and the first upper limit value, the first additional torque of the motor i is taken as the second additional torque of the motor i. If the first additional torque of the motor i is greater than the second upper limit value, the second upper limit value is taken as the second additional torque of the motor i; if the first additional torque of the motor i is less than the second lower limit value, the second lower limit value is taken as the second additional torque of the motor i; if the first additional torque of the motor i is between the second lower limit value and the second upper limit value, the first additional torque of the motor i is taken as the second additional torque of the motor i.

[0085] Further, in an embodiment, the third calculation module 30 is configured to: For the wheel i, the slip ratio error of the wheel i is substituted into the proportional integral algorithm formula to obtain the first additional torque △T i of the motor i corresponding to the wheel i, and the proportional integral algorithm formula is as follows:

[0086] Wherein, K p is a parameter obtained through prior information, K i is a calibration parameter, and e i (t) is the slip ratio error of the wheel i at time t.

[0087] Further, in an embodiment, the second calculation module 20 is configured to: For each wheel, when the slip ratio of the wheel is less than the lower limit value of the target slip ratio, the difference between the lower limit value of the target slip ratio and the slip ratio of the wheel is taken as the slip ratio error of the wheel; when the slip ratio of the wheel is greater than the upper limit value of the target slip ratio, the difference between the upper limit value of the target slip ratio and the slip ratio of the wheel is taken as the slip ratio error of the wheel; when the slip ratio of the wheel is between the upper and lower limits of the target slip ratio, the slip ratio error of the wheel is set to zero.

[0088] Further, in an embodiment, the first calculation module 10 is configured to: For the wheel i, the filtered vehicle speed and the filtered wheel speed of the wheel i are substituted into the slip ratio calculation formula to obtain the slip ratio of the wheel, and the slip ratio calculation formula is as follows:

[0089] Wherein, an effective rolling radius of the wheel i, a filtered vehicle speed, a filtered wheel speed of the wheel i.

[0090] Further, in an embodiment, the motor output torque control apparatus further comprises an output module, configured to: generate a torque request based on the third additional torque of the motor and the current output torque of the motor, and send the torque request to the motor.

[0091] The functions of each module in the motor output torque control apparatus correspond to the steps in the motor output torque control method, and thus the functions and implementation processes are not described here.

[0092] In a third aspect, an embodiment of the present application provides a motor output torque control device. The motor output torque control device can be a motor controller, a vehicle controller, or any other device with data processing capabilities.

[0093] Referring to Figure 3 , Figure 3 FIG. 1 is a schematic diagram of a hardware structure of a motor output torque control device according to an embodiment of the present application. In an embodiment of the present application, the motor output torque control device can include a processor, a memory, a communication interface, and a communication bus.

[0094] The communication bus can be of any type and is used to interconnect the processor, the memory, and the communication interface.

[0095] The communication interface includes input / output (I / O) interfaces, physical interfaces, and logical interfaces, which are used to interconnect devices within the motor output torque control device, and interfaces used to interconnect the motor output torque control device with other devices (e.g., other computing devices or user devices). The physical interface can be an Ethernet interface, a fiber interface, an ATM interface, etc. The user device can be a display (Display), a keyboard (Keyboard), etc.

[0096] The memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0097] The processor can be a general processor, which can invoke a motor output torque control program stored in the memory and execute the motor output torque control method provided by the embodiments of the present application. For example, the general processor can be a central processing unit (CPU). The method executed when the motor output torque control program is invoked can refer to the embodiments of the motor output torque control method of the present application, which will not be described herein.

[0098] Those skilled in the art can understand that, Figure 3 The hardware structure shown in the foregoing embodiments is not a limitation to the present application, and can include more or less components, or combine certain components, or different arrangement of components.

[0099] In a fourth aspect, the embodiments of the present application further provide a computer readable storage medium.

[0100] The computer readable storage medium of the present application stores a motor output torque control program, wherein the motor output torque control program, when executed by a processor, implements the steps of the motor output torque control method as described above.

[0101] The method implemented when the motor output torque control program is executed can refer to the embodiments of the motor output torque control method of the present application, which will not be described herein.

[0102] It should be noted that the serial numbers of the embodiments of the present application are only for description, and do not represent the advantages or disadvantages of the embodiments.

[0103] The terms "comprising" and "having" and any variations thereof in the specification and claims of the present application and the above drawings are intended to cover not exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to the process, method, product or device. The terms "first", "second" and "third" and the like descriptions are used to distinguish different objects, and do not represent the order or limit the types of "first", "second" and "third".

[0104] In the description of the embodiments of the present application, "exemplary", "for example", "for instance" or the like is used to represent an example, illustration or description. Any embodiment or design scheme described as "exemplary", "for example" or "for instance" in the embodiments of the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. On the contrary, the words "exemplary", "for example" or "for instance" are intended to present the relevant concept in a specific manner.

[0105] In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in the text only describes the relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can mean that A exists alone, A and B exist together, and B exists alone, and in addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0106] In some of the processes described in the embodiments of the present application, a plurality of operations or steps are included in a specific order, but it should be understood that these operations or steps can be executed or in parallel without the order in which they appear in the embodiments of the present application, and the serial number of the operation is only used to distinguish different operations, and the serial number itself does not represent any execution order. In addition, these processes can include more or fewer operations, and these operations or steps can be executed in sequence or in parallel, and these operations or steps can be combined.

[0107] From the above description of the embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment method can be realized by means of software and the necessary general hardware platform, of course, it can also be realized by hardware, but in many cases the former is a better embodiment. Based on such understanding, the technical solutions of the present application can be embodied in the form of a software product, which is stored in a storage medium (such as a ROM / RAM, a magnetic disk, an optical disk) as described above, and includes a plurality of instructions for making a terminal device execute the method described in each embodiment of the present application.

[0108] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation using the content of the specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for controlling motor output torque, characterized in that: The motor output torque control method includes: Obtaining the slip rate of each wheel according to the filtered vehicle speed and the filtered wheel speed of each wheel; Obtaining the slip rate error of each wheel based on the upper and lower limits of the target slip rate and the slip rate of each wheel; Based on the slip rate error of each wheel, a first additional torque of the motor corresponding to each wheel is obtained through a proportional integral algorithm; limiting a first additional torque of each motor based on motor capabilities to obtain a second additional torque of each motor; The second additional torque of each motor is optimized to obtain a third additional torque of each motor, so that after the third additional torque of each motor is superimposed on the current output torque of each motor, the yaw moment of the vehicle approaches a preset value, and the total output torque obtained by superimposing the third additional torque of each motor on the current output torque of each motor is not greater than the driving request torque.

2. The motor output torque control method according to claim 1, wherein: Optimizing the second additional torque of each motor to obtain the third additional torque of each motor includes: Solve for x that satisfies the following function to obtain the third additional torque of each motor: Wherein, x is a column vector composed of the third additional torque of multiple motors, △T is a column vector composed of the second additional torque of multiple motors, Tcur is a column vector composed of the current output torque of multiple motors, λ1 and λ2 are weight coefficients, α is a constant vector, T driver Request torque for driving.

3. The motor output torque control method according to claim 1, wherein: The limiting the first additional torque of each motor based on the motor capability to obtain the second additional torque of each motor includes: For motor i, according to the current output torque T of motor i i，cur , the upper limit value T of the output torque of motor i i，max and the lower limit value T of the output torque of motor i i，min Determine the first upper limit value T of the additional torque i，max -T i，cur and the first lower limit value T of the additional torque i，min -T i，cur If the first additional torque of motor i is greater than the first upper limit, the first upper limit is used as the second additional torque of motor i; if the first additional torque of motor i is less than the first lower limit, the first lower limit is used as the second additional torque of motor i; if the first additional torque of motor i is between the first lower limit and the first upper limit, the first additional torque of motor i is used as the second additional torque of motor i; And / or, for motor i, the maximum value of the torque response of motor i is used as the second upper limit value, and the minimum value of the torque response of motor i is used as the second lower limit value. If the first additional torque of motor i is greater than the second upper limit value, the second upper limit value is used as the second additional torque of motor i; if the first additional torque of motor i is less than the second lower limit value, the second lower limit value is used as the second additional torque of motor i; if the first additional torque of motor i is between the second lower limit value and the second upper limit value, the first additional torque of motor i is used as the second additional torque of motor i.

4. The motor output torque control method according to claim 1, wherein: Based on the slip rate error of each wheel, obtaining the first additional torque of the motor corresponding to each wheel through a proportional-integral algorithm includes: For wheel i, the slip rate error of wheel i is substituted into the proportional integral algorithm formula to obtain the first additional torque △T of motor i corresponding to wheel i i , the proportional integral algorithm formula is as follows: Among them, K p is the parameter obtained through prior information, K i is the calibration parameter, e i (t) is the slip rate error of wheel i at time t.

5. The motor output torque control method according to claim 1, wherein: The method of obtaining the slip rate error of each wheel based on the upper and lower limits of the target slip rate and the slip rate of each wheel includes: For each wheel, when the slip rate of the wheel is less than the lower limit value of the target slip rate, the difference between the lower limit value of the target slip rate and the slip rate of the wheel is used as the slip rate error of the wheel; when the slip rate of the wheel is greater than the upper limit value of the target slip rate, the difference between the upper limit value of the target slip rate and the slip rate of the wheel is used as the slip rate error of the wheel; when the slip rate of the wheel is between the upper and lower limits of the target slip rate, the slip rate error of the wheel is set to zero.

6. The motor output torque control method according to claim 1, wherein: Obtaining the slip rate of each wheel according to the filtered vehicle speed and the filtered wheel speed of each wheel includes: For wheel i, substitute the vehicle's filtered speed and wheel i's filtered speed into the slip rate calculation formula to obtain the wheel slip rate: , the slip rate calculation formula is as follows: in, is the effective rolling radius of wheel i, is the filtered speed of the vehicle, is the filtered wheel speed of wheel i.

7. The motor output torque control method according to any one of claims 1 to 6, characterized in that: After optimizing the second additional torque of each motor to obtain the third additional torque of each motor, the method further includes: For each electric machine, a torque request is generated based on the third additional torque of the electric machine and the current output torque of the electric machine, and the torque request is sent to the electric machine.

8. A motor output torque control device, characterized in that: The motor output torque control device includes: a first calculation module, configured to obtain a slip rate of each wheel based on a filtered vehicle speed and a filtered wheel speed of each wheel; a second calculation module, configured to obtain a slip rate error of each wheel based on the upper and lower limits of the target slip rate and the slip rate of each wheel; a third calculation module, configured to obtain a first additional torque of the motor corresponding to each wheel by using a proportional integral algorithm based on a slip rate error of each wheel; a fourth calculation module, configured to limit the first additional torque of each motor based on motor capabilities to obtain a second additional torque of each motor; The optimization module is configured to optimize the second additional torque of each motor to obtain a third additional torque of each motor, so that after the third additional torque of each motor is superimposed on the current output torque of each motor, the yaw moment of the vehicle approaches a preset value, and the total output torque obtained by superimposing the third additional torque of each motor on the current output torque of each motor is not greater than the driving request torque.

9. A motor output torque control device, characterized in that: The motor output torque control device includes a processor, a memory, and a motor output torque control program stored in the memory and executable by the processor, wherein when the motor output torque control program is executed by the processor, the steps of the motor output torque control method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a motor output torque control program, wherein when the motor output torque control program is executed by a processor, the steps of the motor output torque control method according to any one of claims 1 to 7 are implemented.

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