CN117657283A

CN117657283A - Active return control method for electric power steering, vehicle and storage medium

Info

Publication number: CN117657283A
Application number: CN202211006417.XA
Authority: CN
Inventors: 于钦强; 李�根; 赵伟冰; 李明鑫; 李振伟
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2022-08-22
Filing date: 2022-08-22
Publication date: 2024-03-08

Abstract

The application provides an active return control method of electric power steering, a vehicle and a storage medium, wherein the method comprises the following steps: collecting a return control signal; wherein the return control signal comprises a steering wheel steering angle signal and a torque signal; determining an intermediate aligning moment according to the aligning control signal and an advance table stored in the electronic control unit; PID control is carried out according to the intermediate aligning moment, a target aligning moment of the steering wheel is generated, and aligning of the steering wheel is controlled according to the target aligning moment. The target aligning moment of the steering wheel is generated by PID control on the middle aligning moment, the aligning moment based on the vehicle speed is considered in the active aligning moment, the self-adaption based on road conditions and the aligning stability error control are considered, the non-standard road surface can be effectively adapted through the PID control link, and the problem of insufficient steering wheel adjustment or excessive steering caused by driving on the non-standard road surface is avoided.

Description

Active return control method for electric power steering, vehicle and storage medium

Technical Field

The application relates to the technical field of automobile electronic control, in particular to an active alignment control method for electric power steering, a vehicle and a storage medium.

Background

Automobile technology is increasingly developed, and requirements of people on driving experience are also increasingly high. Vehicle ride comfort and steering stability are gaining increasing attention as characteristics that directly affect occupant sensory experience and personal safety. The vehicle steering system is used as a key execution part for controlling the vehicle by a driver, so that the safety and the operability of the whole vehicle are directly determined, and smooth and comfortable steering is important for the safety of the whole vehicle. For the traditional steering mechanism, when the vehicle runs at a low speed, the vehicle has larger friction moment, is unfavorable for aligning, but can effectively inhibit vibration, and has high stability; when the vehicle runs at a high speed, the moment of inertia is large, the overshoot becomes large, and the aligning moment becomes small. However, the return control and the damping control are contradictory, the return is fast, and the dynamic response is good; the damping is big, and stability is good, and interference killing feature is strong, but time of having sacrificed to return. Especially, when the vehicle runs on an nonstandard road surface, the lateral acceleration of the vehicle is gradually increased in the aligning process, and the aligning moment around the master pin at a low speed becomes smaller, so that the phenomena of low-speed aligning deficiency and high-speed aligning overshoot are easy to occur.

Disclosure of Invention

The present application has been made in order to solve the above-described problems. According to an aspect of the present application, there is provided an active return control method of electric power steering, the method including:

collecting a return control signal; wherein the return control signal comprises a steering wheel steering angle signal and a torque signal;

determining an intermediate aligning moment according to the aligning control signal and an advance table stored in the electronic control unit;

PID control is carried out according to the intermediate aligning moment, a target aligning moment of the steering wheel is generated, and aligning of the steering wheel is controlled according to the target aligning moment.

In one embodiment of the present application, collecting a return control signal includes:

and receiving the correction control signal acquired by the torque rotation angle sensor based on a unilateral half-word transmission protocol.

In one embodiment of the present application, determining the intermediate aligning torque from the aligning control signal and an advance table stored in the electronic control unit comprises:

calculating a steering angle of the steering wheel through a vernier algorithm according to the steering angle signal of the steering wheel;

analyzing to obtain the current speed through a controller area network of the vehicle;

and searching the intermediate correcting moment corresponding to the steering angle of the steering wheel and the current vehicle speed in an advance table stored in the electronic control unit.

In one embodiment of the present application, PID control is performed according to the intermediate aligning torque, and generating a target aligning torque of the steering wheel includes:

subtracting the steering angle of the steering wheel from the steering angle of the middle steering wheel corresponding to the middle aligning moment to obtain a difference value;

when the absolute value of the difference value is larger than or equal to a preset threshold value, searching a P value and an I value corresponding to the current vehicle speed in an advance table stored in the electronic control unit;

and carrying out weighted average operation on the product of the difference value and the P value and the product of the integral of the difference value and the I value to obtain the intermediate aligning moment.

In one embodiment of the present application, PID control is performed according to the intermediate aligning torque, so as to generate a target aligning torque of the steering wheel, and the method further includes:

and when the absolute value of the difference value is smaller than the preset threshold value, the PID control is exited, and the step of controlling steering wheel alignment according to the target alignment moment is directly executed.

In one embodiment of the present application, controlling steering wheel alignment according to the target alignment torque includes:

obtaining the moment of the steering wheel according to the moment signal;

searching a gain coefficient corresponding to the steering wheel moment in an advance table stored in the electronic control unit;

smoothing the intermediate aligning moment according to the gain coefficient to obtain the target aligning moment;

and determining a target control current according to the target aligning moment, and sending a control signal corresponding to the target control current to a motor so as to actively align the motor control steering wheel.

In one embodiment of the present application, before determining the target control current from the target aligning torque, the method further comprises:

and determining the direction of the target aligning moment according to the steering of the steering wheel steering angle.

In one embodiment of the present application, determining the direction of the target aligning torque from the steering of the steering wheel steering angle includes:

determining the current steering of the steering wheel according to the angle value of the steering angle of the steering wheel;

and determining the direction of the target aligning moment according to the current steering direction of the steering wheel.

In one embodiment of the present application, when the angle value of the steering angle of the steering wheel is greater than or equal to zero, the current steering direction of the steering wheel is leftward; when the angle value of the steering wheel steering angle is smaller than zero, the current steering of the steering wheel is rightward.

In one embodiment of the present application, wherein the direction of the target aligning torque is the same as the current steering direction.

According to another aspect of the present application, there is provided a vehicle including:

the system comprises a memory and a processor, wherein the memory stores a computer program operated by the processor, and the computer program enables the processor to execute the active alignment control method of the electric power steering when being operated by the processor.

According to still another aspect of the present application, there is provided a storage medium having stored thereon a computer program which, when executed by a processor, causes the processor to execute the above-described active return control method of electric power steering.

According to the method, the vehicle and the storage medium, the target aligning moment of the steering wheel is generated by PID control on the middle aligning moment, the steering wheel aligning is controlled according to the target aligning moment, the aligning moment based on the vehicle speed is not only considered when the steering wheel is controlled to actively align, but also the self-adaption based on road conditions and the aligning stability error control are considered, the problem of insufficient steering wheel adjustment or excessive steering caused by driving on an nonstandard road surface can be effectively solved by PID control.

Drawings

The foregoing and other objects, features and advantages of the present application will become more apparent from the following more particular description of embodiments of the present application, as illustrated in the accompanying drawings. The accompanying drawings are included to provide a further understanding of embodiments of the application and are incorporated in and constitute a part of this specification, illustrate the application and not constitute a limitation to the application. In the drawings, like reference numerals generally refer to like parts or steps.

FIG. 1 shows a schematic flow chart of an active return control method of electric power steering according to an embodiment of the present application;

FIG. 2 shows a schematic block diagram of one example of an active centering system in accordance with an embodiment of the present application;

FIG. 3 shows a schematic flow chart of one example of an active centering control process according to an embodiment of the present application;

FIG. 4 shows a schematic flow chart diagram of a decision process for steering a steering wheel according to an embodiment of the present application;

FIG. 5 shows a schematic flow chart of one example of a feed-forward link control process according to an embodiment of the present application;

FIG. 6 shows a schematic flow chart of one example of a PID control process according to an embodiment of the application;

FIG. 7 shows a schematic flow chart of executing an arbitration module to determine a target aligning torque according to an embodiment of the present application;

fig. 8 shows a schematic diagram of a control current drive execution motor according to an embodiment of the present application;

fig. 9 shows a schematic block diagram of a vehicle according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, exemplary embodiments according to the present application will be described in detail below with reference to the accompanying drawings. It should be apparent that the described embodiments are only some of the embodiments of the present application and not all of the embodiments of the present application, and it should be understood that the present application is not limited by the example embodiments described herein. Based on the embodiments of the present application described herein, all other embodiments that may be made by one skilled in the art without the exercise of inventive faculty are intended to fall within the scope of protection of the present application.

At present, when a driver steers a steering wheel, an electric power steering system (Electric Power Steering, EPS) of a vehicle instructs a motor controller according to the detected steering and torque of the steering wheel to output a steering assist torque of a corresponding magnitude and direction to a motor, thereby generating auxiliary power. In the related art, the active alignment function of the EPS system determines the vehicle speed and the steering wheel angle in the calibration process, so as to determine the alignment current to control the alignment of the vehicle, but the alignment speed is not fixed under different road conditions at the same vehicle speed, so that the phenomenon of uneven steering wheel rotation speed in the alignment process is caused, the alignment effect cannot be ensured, the driving experience is reduced, and the improvement is needed.

Based on the foregoing technical problem, the present application provides an active return control method of electric power steering, where the method includes: collecting a return control signal; determining an intermediate aligning moment according to the aligning control signal and an advance table stored in the electronic control unit; PID control is carried out according to the intermediate aligning moment, a target aligning moment of the steering wheel is generated, and aligning of the steering wheel is controlled according to the target aligning moment. The intermediate aligning moment is subjected to PID control to generate a target aligning moment of the steering wheel, the steering wheel aligning is controlled according to the target aligning moment, the aligning moment based on the vehicle speed is considered in the active aligning process, meanwhile, the self-adaption based on road conditions and the aligning stability error control are considered, the non-standard road surface can be effectively adapted through a PID control link, and the problem of insufficient steering wheel adjustment or excessive steering wheel adjustment caused by driving on the non-standard road surface is avoided.

The following describes in detail a scheme of an active return control method of electric power steering according to an embodiment of the present application with reference to the accompanying drawings. Features of various embodiments of the present application may be combined with one another without conflict.

FIG. 1 shows a schematic flow chart of an active return control method of electric power steering according to an embodiment of the present application; as shown in fig. 1, an active return control method 100 of electric power steering according to an embodiment of the present application may include the following steps S101, S102, and S103:

in step S101, a return control signal is acquired.

Wherein the return control signal comprises a steering wheel steering angle signal and a torque signal.

In one example, collecting the return control signal includes: the return control signal acquired by a torque angle sensor (Torque andAngle Sensor, TAS) is received based on a single-sided half word transfer protocol (Single Edge Nibble Transmission, send).

The present application employs the send protocol to receive back the positive control signal. Send stands for single-sided nibble transmission and complies with the J2716 standard. It supports only unidirectional transmission (only one-way transmission), which means that the sensor can only send data. The SENT sensor differs from other sensors in that multiple data may be "SENT" over one wire. For example, a SENT sensor may use one wire to send pressure and temperature measurements simultaneously. This makes it low cost and reduces wiring requirements. The SENT protocol is a digital signal interface commonly used for sensor signals in automotive electronics, and is an implementation manner of low-cost communication in automotive electronics.

The application adopts a TAS sensor to collect the return control signal. The TAS sensor has the characteristics of low power consumption, low aging deterioration speed and stable angle precision in a wide temperature range, and is suitable for automobile and industrial application.

In step S102, an intermediate aligning torque is determined from the aligning control signal and an advance table stored in the electronic control unit.

In one example, step S102 includes: a1, calculating a steering angle of the steering wheel through a vernier algorithm according to the steering angle signal of the steering wheel; a2, analyzing to obtain the current speed through a controller area network of the vehicle; and step A3, searching the intermediate aligning moment corresponding to the steering angle of the steering wheel and the current vehicle speed in an advance table stored in the electronic control unit.

In step S103, PID control is performed according to the intermediate aligning torque, a target aligning torque of the steering wheel is generated, and steering wheel aligning is controlled according to the target aligning torque.

In one example, PID control is performed according to the intermediate aligning torque, generating a target aligning torque of the steering wheel, including: step B1, subtracting a steering angle of the steering wheel from a steering angle of the steering wheel corresponding to the middle correcting moment to obtain a difference value; step B2, when the absolute value of the difference value is larger than or equal to a preset threshold value, searching a P value and an I value corresponding to the current vehicle speed in an advance table stored in the electronic control unit; and B3, carrying out weighted average operation on the product of the difference value and the P value and the product of the integral of the difference value and the I value to obtain the intermediate aligning moment.

In one example, controlling steering wheel alignment according to the target alignment torque includes: step C1, obtaining the moment of the steering wheel according to the moment signal; step C2, searching a gain coefficient corresponding to the steering wheel moment in an advance table stored in the electronic control unit; step C3, smoothing the intermediate aligning moment according to the gain coefficient to obtain the target aligning moment; and step C4, determining a target control current according to the target aligning moment, and sending a control signal corresponding to the target control current to a motor so as to enable the motor to control the steering wheel to be actively aligned.

Before determining the target control current according to the target aligning torque, the method further comprises: and determining the direction of the target aligning moment according to the steering of the steering wheel steering angle. Specifically, determining the direction of the target aligning torque according to the steering of the steering wheel steering angle includes: step D1, determining the current steering of the steering wheel according to the angle value of the steering angle of the steering wheel; and D2, determining the direction of the target aligning moment according to the current steering direction of the steering wheel.

When the angle value of the steering angle of the steering wheel is larger than or equal to zero, the current steering of the steering wheel is leftward; when the angle value of the steering wheel steering angle is smaller than zero, the current steering of the steering wheel is rightward.

Wherein the direction of the target aligning torque is the same as the current steering direction.

In the present application, the steering wheel of the vehicle is subjected to the active return operation under the control of the active return system. The process and principle of the active steering system of the vehicle for controlling the steering wheel to actively steer will be described in detail.

As shown in fig. 2, the active return system includes an electronic control unit (Electronic Control Unit, ECU) that can provide basic assistance to the steering wheel. The ECU comprises a basic power-assisted module and a motor control module, wherein the basic power-assisted module comprises an active alignment module, and the active alignment module comprises a steering judging module, a feedforward link module, a PIC control module and an arbitration module. The active correcting module extracts an active correcting control signal (a steering wheel moment signal T and a steering wheel steering angle signal A) sent by the TAS sensor and the current vehicle speed v obtained through CAN network analysis.

The basic power assisting module can send the calculated target torque to the motor control module, and the motor control module generates a target current signal according to the target torque and sends the target current signal to the execution motor so as to control the steering wheel to actively return.

In step S1 executed by the steering determination module, as shown in fig. 4, the steering angle of the steering wheel may be determined according to the steering angle signal of the steering wheel, and if the steering angle of the steering wheel is equal to or greater than 0, the steering of the steering wheel is left-turned, otherwise, right-turned. The steering state of the steering wheel and the sign value sign (angle), i.e., ±1, are then output.

In step S2 executed by the feed-forward link module, the steering state of the vehicle may be determined according to the steering angle of the steering wheel, and then the left-turn module or the right-turn module of the steering system is scheduled, and the left-turn module or the right-turn module performs searching of an advance table stored in the electronic control unit based on the current vehicle speed and the absolute value of the steering angle of the steering wheel to obtain an intermediate aligning moment.

As shown in fig. 5, the absolute value of the steering angle of the steering wheel is first taken, and when the steering wheel turns left, the advance table stored in the electronic control unit is searched according to the current vehicle and the steering angle of the steering wheel, so as to obtain the middle correcting moment corresponding to the left turning. When the steering wheel turns right, according to the current steering angle of the vehicle and the steering wheel, searching an advance table stored in the electronic control unit to obtain an intermediate aligning moment corresponding to the right turning, outputting the intermediate aligning moment, and then obtaining a feedforward value.

In step S3 executed by the PID control module, as shown in fig. 6, a difference operation is performed by subtracting the actual steering angle absolute value from the intermediate steering angle (the threshold value of the steering angle) corresponding to the intermediate aligning torque, that is, err=threshold value-angle. And searching an advance table stored in the electronic control unit according to the current vehicle speed to obtain a P value and an I value respectively. Then the difference value is multiplied by a P value (Err. Times.P), the integral of the difference value is multiplied by an I value (I ≡ (Err) dt), and then the two are overlapped (namely weighted average) to finally obtain a calculation result of a PI compensation value, wherein the PI compensation value is a target aligning moment obtained according to a PID control method.

It is noted that, in step S3, when the absolute value |err| of the difference between the steering angle of the intermediate steering wheel corresponding to the intermediate aligning torque and the actual steering angle is < a preset threshold value, the PID control (not shown) is exited to prevent the overshoot; and carrying out weighted average on the PI control result and the feedforward control result, wherein the formula is as follows: aligning torque=k PI + (1-k) feedforward values, where the weighting value k can be manually set to obtain the absolute value of the final target aligning torque.

In step S4 executed by the arbitration module, a steering wheel torque T may be obtained according to the steering wheel torque signal, and an advance table stored in the electronic control unit is searched according to the steering wheel torque T, so as to obtain a gain coefficient corresponding to the steering wheel torque. The process can effectively smooth the moment of the alignment state; taking a sign value +/-1 of a steering wheel steering angle or a steering wheel rotating speed, wherein the sign of the steering wheel steering angle can be used for supplementing a target aligning moment in the direction because each value corresponding to left and right steering of the steering wheel, which is determined by searching an advance table stored in an electronic control unit, cannot be distinguished from each value obtained during PID control; then obtaining a final target aligning moment; the final target aligning torque can be obtained by multiplying the gain value, the steering wheel rotating speed sign value (namely + -1) and the intermediate aligning torque value.

As shown in fig. 7, looking up the advance table stored in the electronic control unit based on the steering wheel torque results in a gain factor that will bring the steering wheel back to positive. And meanwhile, the PI compensation value is overlapped with the feedforward value calculated in the step S2, and an overlapped value is obtained. The gain factor is then multiplied by the superimposed value multiplied by the sign value of the steering wheel angle, i.e. the gain factor superimposed value sign (angle), to obtain a signed target aligning moment.

The PID control is carried out on the middle correcting moment to generate a target correcting moment of the steering wheel, the steering wheel is controlled to be corrected according to the target correcting moment, the correcting moment based on the vehicle speed is considered in the active correcting moment, meanwhile, the self-adaption based on road conditions and the condition of correcting stability error control are considered, the PI control link can be effectively adapted to an nonstandard road surface, and the problem of insufficient steering wheel adjustment or excessive steering wheel adjustment caused by driving on the nonstandard road surface is avoided.

Further, as shown in fig. 3, a flow chart of the active return system for controlling the active return of the steering wheel is shown. When the active alignment process starts to be executed, a signal processing module (not shown) receives a steering wheel steering angle signal and a steering wheel moment signal SENT by a TAS sensor through a SENT protocol, the signal processing module calculates a steering wheel angle A through the steering wheel steering angle signal through a vernier algorithm, obtains a steering wheel moment T through protocol analysis, obtains a steering wheel rotating speed omega through deriving the steering wheel steering angle, and obtains the current speed V of the vehicle according to CAN network analysis of the vehicle.

In step S1, the steering state of the steering wheel is determined. The steering angle A of the steering wheel can be determined according to the steering angle signal A of the steering wheel, if the steering angle A of the steering wheel is more than or equal to 0, the steering of the steering wheel is left-turning, otherwise, the steering is right-turning.

In step S2, corresponding feedforward control is performed based on the rotation direction. The steering state of the vehicle can be determined according to the steering angle of the steering wheel, and then a left-turning module or a right-turning module of the steering system is scheduled, and the left-turning module or the right-turning module searches an advance table stored in the electronic control unit based on the current vehicle speed and the absolute value of the steering angle of the steering wheel to obtain an intermediate aligning moment.

In step S3, compensation control is performed for undercorrected or overcorrected based on PID. The method comprises the steps of performing difference operation according to an intermediate steering wheel steering angle corresponding to an intermediate aligning torque minus an actual steering wheel steering angle absolute value, searching an advance table stored in an electronic control unit according to a current vehicle speed to obtain a P value and an I value, multiplying the difference by the P value and the I value respectively, integrating the product of the difference and the I value to obtain a PI calculation result, and exiting PID control when the intermediate steering wheel steering angle corresponding to the intermediate aligning torque and the absolute value |Err| < a preset threshold value of the actual steering angle difference value so as to prevent over-adjustment; and carrying out weighted average on the PI control result and the feedforward control result, wherein the formula is as follows: aligning torque=k PI + (1-k) feedforward values, where the weighting value k can be manually set to obtain the final target aligning torque.

In step S4, an arbitration module is executed to determine the direction of the target aligning torque. The steering wheel moment T can be obtained according to the steering wheel moment signal, and an advance table stored in the electronic control unit is searched according to the steering wheel moment T so as to obtain a gain coefficient corresponding to the steering wheel moment. The process can effectively smooth the moment of the alignment state; taking a sign value +/-1 of a steering wheel steering angle or a steering wheel rotating speed, wherein the sign of the steering wheel steering angle can be used for supplementing a target aligning moment in the direction because each value corresponding to left and right steering of the steering wheel, which is determined by searching an advance table stored in an electronic control unit, cannot be distinguished from each value obtained during PID control; then obtaining a final target aligning moment; the final target aligning torque can be obtained by multiplying the gain value, the steering wheel rotating speed sign value (namely + -1) and the intermediate aligning torque value.

The above steps, when executed, may determine the execution order according to the actual situation, and the present embodiment is not intended to limit the order.

In another embodiment of the present application, as shown in fig. 8, the signal processing module receives the steering wheel steering angle signal and the steering wheel torque signal SENT by the TAS sensor via the send protocol. The signal processing module calculates a steering wheel angle A through a vernier algorithm by a steering wheel steering angle signal, obtains a steering wheel moment T through protocol analysis, obtains a steering wheel rotating speed omega by deriving the steering wheel steering angle, and obtains the current speed V of the vehicle according to CAN network analysis of the vehicle. And then calculating the parameters through a basic power-assisted module to obtain the final target aligning moment. And then the target aligning moment is sent to a motor control module, the motor control module generates control current according to the target aligning moment, the control current is sent to an execution motor, and the execution motor generates feedback current and sends the feedback current back to the motor control module. And meanwhile, the motor is executed to run to generate basic assistance, and a driver obtains steering assistance of the steering wheel according to the basic assistance.

The embodiment of the application has the following beneficial effects:

(1) Compared with the traditional method for actively correcting control based on the mode of detecting the state of the driver through the TAS sensor, the method is also based on the data acquired by the TAS sensor, and the hardware cost is not required to be increased additionally.

(2) In the application, the correction moment based on the vehicle speed is not only considered when the steering wheel is actively corrected, but also the situation of error control of correction stability based on road condition self-adaption is considered, the steering wheel can be effectively adapted to an nonstandard road surface through a PID control link, and the problem of insufficient adjustment or excessive adjustment of the steering wheel caused by driving on the nonstandard road surface is avoided.

(3) The correction control in the traditional technology judges whether the vehicle is in a correction state through the directional product of the steering wheel angle and the steering wheel rotating speed, when overshoot occurs, the whole vehicle is still in the correction state, but the correction function is stopped, compared with the traditional technology, the steering state is judged by utilizing the steering wheel angle, the gain coefficient is determined by the steering wheel moment, the accuracy of the correction state judgment is ensured, and meanwhile, the smoothness of the steering wheel moment is ensured when the correction state is switched to other states.

(4) The feedforward control is combined with the PID control, the feedforward control can ensure the response speed of the system, the PID control can ensure the accuracy of the control, and in the aligning process, the smoothness and reliability of aligning moment are ensured, and the characteristics of self-adaption of different road conditions are realized.

(5) The method establishes a boundary value (preset threshold) in the PID control, and when the boundary value is reached, the PID control is exited, and the adjustment is performed based on feedforward, so that the risk of overshoot is prevented.

(6) The electric power steering system and the control algorithm thereof can adjust steering in real time according to the operating state of a driver and the motion information of the vehicle so as to adapt to different road conditions, so that the vehicle always operates in an optimal state, and further, the contradiction between the operating stability and smoothness is solved.

The vehicle of the present application is described below in connection with fig. 9, wherein fig. 9 shows a schematic block diagram of the vehicle according to an embodiment of the present application.

As shown in fig. 9, a vehicle 900 includes: one or more memories 901 and one or more processors 902, the memory 901 having stored thereon a computer program to be executed by the processor 902, which when executed by the processor 902, causes the processor 902 to perform the aforementioned active return control method of electric power steering.

The vehicle 900 may be part or all of a computer device that may implement the active centering control method of electric power steering by software, hardware, or a combination of software and hardware.

As shown in fig. 9, vehicle 900 includes one or more memories 901, one or more processors 902, a display (not shown), and a communication interface, etc., interconnected by a bus system and/or other forms of connection mechanisms (not shown). It should be noted that the components and configuration of the vehicle 900 shown in fig. 9 are exemplary only and not limiting, as the vehicle 900 may have other components and configurations as desired.

The memory 901 is used to store various data and executable program instructions generated during the operation of the method of the present application, such as algorithms for storing various application programs or algorithms for performing various specific functions. One or more computer program products may be included that may include various forms of computer-readable storage media, such as volatile and/or nonvolatile memory. The volatile memory may include, for example, random Access Memory (RAM) and/or cache memory (cache), and the like. The non-volatile memory may include, for example, read Only Memory (ROM), hard disk, flash memory, and the like.

The processor 902 may be a Central Processing Unit (CPU), an image processing unit (GPU), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or other form of processing unit having data processing and/or instruction execution capabilities, and may be other components in the vehicle 900 to perform desired functions.

In one example, the vehicle 900 further includes an output device that may output various information (e.g., images or sounds) to the outside (e.g., a user), and may include one or more of a display device, a speaker, and the like.

The communication interface is an interface that may be any presently known communication protocol, such as a wired interface or a wireless interface, where the communication interface may include one or more serial ports, USB interfaces, ethernet ports, wiFi, wired network, DVI interfaces, device integration interconnect modules, or other suitable various ports, interfaces, or connections.

Furthermore, according to an embodiment of the present application, there is also provided a storage medium on which program instructions are stored, which program instructions, when executed by a computer or a processor, are adapted to carry out the respective steps of the active return control method of electric power steering of the embodiment of the present application. The storage medium may include, for example, a memory card of a smart phone, a memory component of a tablet computer, a hard disk of a personal computer, read-only memory (ROM), erasable programmable read-only memory (EPROM), portable compact disc read-only memory (CD-ROM), USB memory, or any combination of the foregoing storage media.

The vehicle and the storage medium according to the embodiments of the present application have the same advantages as the active return control method of electric power steering described above, since the method described above can be implemented.

Although the illustrative embodiments have been described herein with reference to the accompanying drawings, it is to be understood that the above illustrative embodiments are merely illustrative and are not intended to limit the scope of the present application thereto. Various changes and modifications may be made therein by one of ordinary skill in the art without departing from the scope and spirit of the present application. All such changes and modifications are intended to be included within the scope of the present application as set forth in the appended claims.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described device embodiments are merely illustrative, e.g., the division of the elements is merely a logical functional division, and there may be additional divisions when actually implemented, e.g., multiple elements or components may be combined or integrated into another device, or some features may be omitted or not performed.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the present application may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Similarly, it should be appreciated that in order to streamline the application and aid in understanding one or more of the various inventive aspects, various features of the application are sometimes grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of the application. However, the method of this application should not be construed to reflect the following intent: i.e., the claimed application requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this application.

It will be understood by those skilled in the art that all of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or units of any method or apparatus so disclosed, may be combined in any combination, except combinations where the features are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features but not others included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the present application and form different embodiments. For example, in the claims, any of the claimed embodiments may be used in any combination.

Various component embodiments of the present application may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that some or all of the functions of some of the modules according to embodiments of the present application may be implemented in practice using a microprocessor or Digital Signal Processor (DSP). The present application may also be embodied as device programs (e.g., computer programs and computer program products) for performing part or all of the methods described herein. Such a program embodying the present application may be stored on a computer readable medium, or may have the form of one or more signals. Such signals may be downloaded from an internet website, provided on a carrier signal, or provided in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the application, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The application may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The use of the words first, second, third, etc. do not denote any order. These words may be interpreted as names.

The foregoing is merely illustrative of specific embodiments of the present application and the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes or substitutions are intended to be covered by the scope of the present application. The protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An active return control method of electric power steering, characterized in that the method comprises:

2. The method of claim 1, wherein collecting the return control signal comprises:

3. The method of claim 1, wherein determining an intermediate aligning torque from the aligning control signal and an advance table stored in an electronic control unit comprises:

4. The method of claim 1, wherein generating the target aligning torque of the steering wheel based on the intermediate aligning torque for PID control comprises:

5. The method of claim 4, wherein PID control is based on the intermediate aligning torque to generate a target aligning torque for the steering wheel, further comprising:

6. The method of claim 1, wherein controlling steering wheel alignment in accordance with the target alignment torque comprises:

obtaining the moment of the steering wheel according to the moment signal;

7. The method of claim 6, wherein prior to determining a target control current from the target aligning torque, the method further comprises:

8. The method of claim 7, wherein determining the direction of the target aligning torque based on the steering of the steering wheel steering angle comprises:

9. The method of claim 8, wherein the current steering of the steering wheel is to the left when the angle value of the steering wheel steering angle is equal to or greater than zero; when the angle value of the steering wheel steering angle is smaller than zero, the current steering of the steering wheel is rightward.

10. The method of claim 8, wherein the direction of the target aligning torque is the same as the current steering direction.

11. A vehicle, characterized in that the vehicle comprises:

a memory and a processor, the memory having stored thereon a computer program to be executed by the processor, which when executed by the processor, causes the processor to perform the active return control method of electric power steering as claimed in any one of claims 1 to 10.

12. A storage medium having stored thereon a computer program which, when executed by a processor, causes the processor to perform the active return control method of electric power steering as claimed in any one of claims 1 to 10.