Steering angle neutral position compensation control method and apparatus for steering system, and vehicle and storage medium

Abstract

The present application belongs to the technical field of vehicles. Disclosed are a steering angle neutral position compensation control method and apparatus for an electric power steering system, and a vehicle and a storage medium. On the basis of initial neutral position calibration information of a TAS sensor, preset rotor neutral position information of a rotor of an electric motor is correspondingly obtained; when a vehicle is in a travelling-straight state, a steering wheel neutral position reference value is acquired; and vehicle rotor steering angle position information is acquired, and after the latest acquired steering wheel neutral position reference value is used for performing deviation determination, calculation is performed on the vehicle rotor steering angle position information having a relatively large deviation using the steering wheel neutral position reference value that meets a duration condition and has been subjected to self-learning, so as to obtain a high-precision target steering wheel steering angle value.

Description

Steering system turning angle mid-position compensation control method and device, vehicle and storage medium

[0001] Cross-reference to related applications

[0002] This application is based on and claims priority to Chinese Patent Application No. 202410829863.3, filed on June 25, 2024, the entire contents of which is incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to the technical field of vehicles, in particular to a control method and device for compensating for the mid-position of the turning angle of an electric power steering system, a vehicle and a storage medium. BACKGROUND

[0004] In recent years, with the popularization of passenger cars, electric power steering systems (EPS) have become a standard configuration for passenger cars. The EPS system can provide the driver with steering assistance that varies with vehicle speed based on the torque applied to the steering wheel by the driver and the magnitude of the different vehicle speeds, achieving a driving feel of "low-speed steering light and high-speed steering stable". The development of automatic driving technology has improved the safety, comfort and convenience of driving, and the electric power steering system can meet the lateral control function of the vehicle for advanced automatic driving such as lane keeping assistance, automatic parking, and advanced adaptive cruise control, and has gained the favor of the majority of car consumers.

[0005] However, in the actual production, manufacturing and assembly process of vehicles and parts, due to the cumulative reasons of design tolerance, manufacturing error and assembly error, there are cases where the size of the vehicle is not symmetrical. In addition, deformation, wear and tear of parts during vehicle use will eventually cause the mid-position of the turning angle provided by the steering wheel turning angle sensor to be inconsistent with the mid-position when the vehicle is driving straight, causing the steering wheel turning angle value provided by the steering wheel turning angle sensor to have a certain deviation from the actual turning angle of the vehicle during driving. Further, it causes deviations in vehicle deviation control, trajectory planning of parking functions, etc. The existing solution is usually to re-calibrate the mid-position of the turning angle sensor by professional technicians, which is relatively high in maintenance efficiency and cost, and is not convenient for users. SUMMARY

[0006] The present application aims to provide a control method and device for compensating for the mid-position of the turning angle of an electric power steering system, a vehicle and a storage medium to solve one or more technical problems in the prior art and at least provide a beneficial choice or create conditions.

[0007] The application provides a control method for mid-position compensation of an electric power steering system, which is applied to an electric power steering system with a motor and includes the following steps: obtaining preset rotor mid-position information of the motor; obtaining rotor angle position information of the motor as current rotor mid-position information when the vehicle is in a straight running state; calculating a steering wheel mid-position reference value according to the preset rotor mid-position information and the current rotor mid-position information, wherein the steering wheel mid-position reference value is used to represent an angle value of the steering wheel deviating from a mid-position when the vehicle is in the straight running state; obtaining rotor angle position information of the motor, and calculating an initial steering wheel angle value according to the preset rotor mid-position information and the rotor angle position information; determining a target steering wheel angle value according to the steering wheel mid-position reference value and the initial steering wheel angle value, and sending the target steering wheel angle value to a bus.

[0008] The technical scheme has at least the following beneficial effects: when the vehicle is in the straight running state, the current rotor mid-position information is obtained, and the steering wheel mid-position reference value is calculated according to the preset rotor mid-position information; after the initial steering wheel angle is obtained, the target steering wheel angle value is calculated according to the steering wheel mid-position reference value and the initial steering wheel angle. That is, when the vehicle is in the straight running state, the deviation between the preset rotor mid-position information and the straight running state of the vehicle is determined according to the steering wheel mid-position reference value, and the initial steering wheel angle is corrected and compensated according to the deviation, so that a more accurate target steering wheel angle value can be obtained. The target steering wheel angle value can more accurately represent the actual steering angle position of the vehicle, and the target steering wheel angle value is sent to the bus. When the control system obtains and uses the target steering wheel angle value, the accuracy of the steering angle of the vehicle deviation control, the parking function trajectory planning and the like can be improved. Therefore, it is not necessary to re-calibrate the preset rotor mid-position information by professional personnel, so that the maintenance workload and cost are reduced, and the user can use it conveniently. Meanwhile, compared with the method of directly measuring the steering shaft angle to obtain the steering wheel angle value, the rotor position mid-position of the EPS system with high precision is calibrated, and the initial steering wheel angle value is calculated, and the steering wheel mid-position reference value and the initial steering wheel angle value are both obtained through the rotor position information of the motor in the EPS system, so that the error of the correction and compensation calculation can be reduced, and the calculation result is more accurate.

[0009] In some embodiments, the obtaining of the preset rotor mid-position information of the motor includes: obtaining initial mid-position calibration information of a TAS sensor, and determining the preset rotor mid-position information according to the initial mid-position calibration information, wherein the TAS sensor is used to detect the steering wheel angle of the vehicle. The TAS sensor mid-position calibration is easier than the rotor mid-position calibration, so that the difficulty of the rotor mid-position calibration can be reduced.

[0010] In some embodiments, determining the target steering wheel rotation angle value according to the steering wheel center reference value and the initial steering wheel rotation angle value comprises: when the steering wheel center reference value is within a first threshold range, taking the initial steering wheel rotation angle value as the target steering wheel rotation angle value. If the deviation of the steering wheel center reference value is not large, it can be considered that the correspondence between the initial steering wheel rotation angle and the actual vehicle rotation angle position is not large, so that the initial steering wheel rotation angle does not need to be corrected and compensated to accurately represent the actual vehicle rotation angle position.

[0011] In some embodiments, the target steering wheel rotation angle value is determined according to the steering wheel center reference value and the initial steering wheel rotation angle value, comprising: when the steering wheel center reference value is outside the first threshold range, the target steering wheel rotation angle value is calculated by the following formula: rAngle SW = fAngle SW - c x C p ; wherein fAngle SW is the initial steering wheel rotation angle value; rAngle SW is the target steering wheel rotation angle value; c is the steering wheel center reference value; C p is a rotation angle center compensation coefficient. According to the calibrated rotation angle center compensation coefficient, the steering wheel center reference value is adjusted, and then the initial steering wheel rotation angle value with large deviation is corrected and compensated by reducing and increasing. Even in a large range of deviation, the initial steering wheel rotation angle value can be properly corrected and compensated.

[0012] In some embodiments, the control method further comprises: obtaining a straight driving time duration value when the vehicle is in a straight driving state; and updating the steering wheel center reference value with the current steering wheel center reference value when the straight driving time duration value is greater than or equal to a fourth threshold value. The steering wheel center reference value collected after the vehicle is in a straight driving state for a period of time can more accurately represent the deviation value of the preset rotor center information. With the accurate steering wheel center reference value as the basis for correction and compensation, the correctness and accuracy of the correction and compensation can be better guaranteed.

[0013] In some embodiments, the initial steering wheel rotation angle value is calculated according to the preset rotor center information and the rotor rotation angle position information, comprising: determining a rotor rotation angle value according to the preset rotor center information and the rotor rotation angle position information; and calculating the initial steering wheel rotation angle value by the following formula: fAngle SW = Angle motor / (S 减速比 * I 传动比 ); wherein fAngle SW is the initial steering wheel rotation angle value; Angle motor is the rotor rotation angle value; S 减速比A transmission ratio of a speed reduction mechanism in an electric power steering system; I 传动比 A gear and rack transmission ratio in an electric power steering system. According to the mechanical connection characteristics of the electric power steering system, the rotor angle position information is converted into an initial steering wheel angle value, ensuring the accuracy of the calculation of the initial steering wheel angle value.

[0014] In some embodiments, the control method further comprises: obtaining the target steering wheel angle value; and controlling the motor to assist the steering wheel rotation according to the target steering wheel angle value. The target steering wheel angle value with higher accuracy is used to determine the steering wheel rotation status, and the steering wheel rotation is assisted according to the more accurate actual situation of the steering wheel, thereby improving the effect of controlling the steering wheel to realize the functions of steering return, vehicle deviation control, ADAS lateral request, etc.

[0015] In some embodiments, the control method further comprises: determining that the vehicle is in a straight running state when the following conditions are met simultaneously: the vehicle speed of the vehicle is not less than a fifth threshold value; the wheel speed difference between the left front wheel and the right front wheel of the vehicle is less than or equal to a sixth threshold value; the difference between the sum of the left front wheel speed and the right rear wheel speed and the sum of the right front wheel speed and the left rear wheel speed of the vehicle does not exceed a seventh threshold value; the yaw rate of the vehicle does not exceed an eighth threshold value; and the steering wheel torque value of the vehicle does not exceed a ninth threshold value. When the vehicle is running at a certain speed, the values of the wheel speed difference, the vehicle yaw rate, and the steering wheel torque value are determined, and under the above conditions, it is sufficient to exclude various situations when the vehicle is not in a straight running state. Since the steering wheel and the steering wheel are mechanically connected in the EPS system, only the instantaneous straight running state of the vehicle needs to be determined, which can be used to determine the deviation of the preset rotor midpoint information.

[0016] An apparatus for compensating the midpoint of the steering angle of an electric power steering system, comprising: an acquisition module, configured to: acquire preset rotor midpoint information of the motor; acquire rotor angle position information of the motor as current rotor midpoint information when the vehicle is in a straight running state; and acquire the rotor angle position information of the motor; and a processing module, configured to: calculate a steering wheel midpoint reference value according to the preset rotor midpoint information and the current rotor midpoint information, the steering wheel midpoint reference value being used to represent an angle value of the steering wheel deviating from the midpoint position when the vehicle is in a straight running state; calculate an initial steering wheel angle value according to the preset rotor midpoint information and the rotor angle position information; determine a target steering wheel angle value according to the steering wheel midpoint reference value and the initial steering wheel angle value, and send the target steering wheel angle value to a bus.

[0017] In some embodiments, the acquisition module comprises a TAS sensor, the TAS sensor being configured to acquire initial median calibration information of the TAS sensor, and the preset median information of the rotor is determined according to the initial median calibration information, wherein the TAS sensor is configured to detect a steering wheel rotation angle of the vehicle.

[0018] In some embodiments, the processing module comprises a function logic calculation module, the function logic calculation module being configured to acquire the target steering wheel rotation angle value, and the motor auxiliary steering is controlled according to the target steering wheel rotation angle value.

[0019] A vehicle comprises a memory and a processor, the memory storing a computer program, and the processor is configured to run the computer program to execute any one of the above-mentioned electric power assisted steering system rotation angle median compensation control methods.

[0020] A storage medium storing a computer program, wherein the computer program is configured to execute any one of the above-mentioned electric power assisted steering system rotation angle median compensation control methods when running on a computer or a processor. BRIEF DESCRIPTION OF DRAWINGS

[0021] The drawings described herein are used to provide an understanding of the present application, and form a part of the present application. The illustrative embodiments of the present application and their description serve to explain the present application. They do not limit the present application in any way. In the drawings:

[0022] Fig. 1 is a flow chart of an electric power assisted steering system rotation angle median compensation control method according to an embodiment of the present application;

[0023] Fig. 2 is a specific flow chart of an electric power assisted steering system rotation angle median compensation control method according to an embodiment of the present application;

[0024] Fig. 3 is a flow chart of an electric power assisted steering system rotation angle median compensation control method according to an embodiment of the present application;

[0025] Fig. 4 is a structural block diagram of a control device according to an embodiment of the present application;

[0026] Fig. 5 is a process diagram of an electric power assisted steering system rotation angle median compensation control method according to an embodiment of the present application. DETAILED DESCRIPTION

[0027] In the following, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application, so that those skilled in the art can better understand the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work should fall within the scope of the present application.

[0028] It should be noted that the terms "first", "second" and the like in the description and claims of the present application and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the terms used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0029] According to the embodiments of the present application, an embodiment of a control method for electric power assisted steering system corner mid-compensation is provided. It should be noted that the steps shown in the flowchart of the drawings can be executed in a computer system including at least one set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in an order different from that shown herein.

[0030] The method embodiment can also be executed in an electronic device / apparatus including a memory and a processor, a similar control device or a cloud. Taking the electronic device / apparatus as an example, the electronic device / apparatus can include one or more processors and a memory for storing data. Optionally, the above-mentioned electronic device / apparatus can also include a communication device for communication function and a display device. Those skilled in the art can understand that the above structural description is only illustrative, and does not limit the structure of the above-mentioned electronic device / apparatus. For example, the electronic device / apparatus can also include more or less components than the above structural description, or have a different configuration from the above structural description.

[0031] The processor can include one or more processing units. For example, the processor can include processing devices such as a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processing (DSP) chip, a microcontroller unit (MCU), a field-programmable gate array (FPGA), a neural-network processing unit (NPU), a tensor processing unit (TPU), an artificial intelligent (AI) type processor, and the like. Different processing units can be independent components or integrated in one or more processors. In some examples, the electronic device can also include one or more processors.

[0032] The memory can be used to store a computer program, for example, a computer program corresponding to the vehicle control method in the embodiments of the present application. The processor implements the vehicle control method described above by running the computer program stored in the memory. The memory can include a high-speed random access memory, and can also include a non-volatile memory such as one or more magnetic storage devices, flash memories, or other non-volatile solid-state memories. In some examples, the memory can include a memory remotely disposed relative to the processor, which can be connected to the electronic device through a network. Examples of the network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0033] As shown in FIGS. 1-2, a control method for electric power steering system corner mid-position compensation includes the following steps:

[0034] Step S100, obtaining preset rotor mid-position information of the motor.

[0035] Specifically, the preset rotor mid-position information is information for calibrating the position of the motor according to the vehicle mid-position (i.e., the vehicle straight driving posture or the intermediate posture without cornering) when the vehicle is off-line or during production. The preset rotor mid-position information is needed when calculating the rotor position of the motor.

[0036] It can be understood that the preset rotor mid-position information can be directly obtained from the vehicle mid-position, or indirectly obtained from other components or sensors.

[0037] Step S200, when the vehicle is in the straight running state, the rotor angle position information of the motor is obtained as the current rotor neutral position information.

[0038] Specifically, when the vehicle is in the straight running state, the corresponding motor is in the neutral position at this time, and the rotor angle position information of the motor obtained at this time is the current rotor neutral position information. Generally, in the case of no deviation, the current rotor neutral position information should correspond to zero, i.e., the preset rotor neutral position information. If the current rotor neutral position information deviates from zero or the preset rotor neutral position information, the rotor angle position information calculated according to the preset rotor neutral position information will also deviate, and thus whether there is a deviation can be determined by obtaining the current rotor neutral position information at this time.

[0039] It can be understood that the current rotor neutral position information of the motor can be directly or indirectly obtained by a sensor component such as an angle sensor.

[0040] Step S300, the steering wheel neutral reference value is calculated according to the preset rotor neutral position information and the current rotor neutral position information, and the steering wheel neutral reference value is used to represent the angle value of the steering wheel deviating from the neutral position corresponding to the vehicle in the straight running state.

[0041] Specifically, the preset rotor neutral position information is set according to the standard state when the vehicle is off the line or before initial use, and the current rotor neutral position information is obtained by the vehicle in the straight running state. Taking the current rotor neutral position information as the current vehicle neutral position, the steering wheel neutral reference value obtained by comparing or calculating the two can represent the deviation of the current preset rotor neutral position information and the current vehicle neutral position, so that the deviation can be used to correct and compensate the subsequent steering wheel angle.

[0042] It can be understood that the calculation of the steering wheel neutral reference value can be performed by a formula with preset rotor neutral position information and current rotor neutral position information parameters, or by comparing the preset rotor neutral position information and the current rotor neutral position information to obtain the steering wheel neutral reference value.

[0043] Step S400, the rotor angle position information of the motor is obtained, and the initial steering wheel angle value is calculated according to the preset rotor neutral position information and the rotor angle position information.

[0044] Specifically, the motor's position information is the rotor angle position information. Since there is a defined transmission relationship between the motor and the steering wheel shaft, the rotor angle position information can characterize the steering wheel angle. Some system controllers on the vehicle need to collect steering wheel angle information to determine the vehicle's driving status. Therefore, the EPS system can calculate a precise target steering wheel angle value by correcting and compensating the rotor angle position information, and then send the target steering wheel angle value to the bus for use by relevant controllers. This improves the accuracy and reliability of related control functions. The preset rotor center position information is set according to the standard state when the vehicle is off the production line or before initial use, and is also used in step S300 above to calculate the steering wheel center position reference value. Therefore, this initial steering wheel angle value and the steering wheel center position reference value are calculated using the same benchmark, ensuring the correlation between the two data. In subsequent steps, the initial steering wheel angle value is corrected and compensated using the steering wheel center position reference value, resulting in a more accurate target steering wheel angle value.

[0045] It is understandable that the rotor angle position information of the motor can be obtained directly or indirectly through sensor components such as angle sensors. This step can be obtained through the instruction program set by the vehicle's main controller, or it can be performed automatically by the internal program of the EPS system. The initial steering wheel angle value can be calculated using a formula with preset rotor center position information and rotor angle position information parameters, or a steering wheel center position reference value can be obtained by comparing the preset rotor center position information and rotor angle position information.

[0046] In addition, this embodiment also provides a method for calculating the steering wheel angle based on the position of the motor rotor:

[0047] The rotor angle value is determined based on the preset rotor center position information and rotor angle position information; the initial steering wheel angle value is calculated using the following formula: fAngle SW =Angle motor / (S 减速比 *I 传动比 )

[0048] Among them, fAngle SW This is the initial steering wheel angle;

[0049] Angle motor This represents the rotor angle value.

[0050] S 减速比 This refers to the gear ratio of the reduction mechanism in an electric power steering system.

[0051] I 传动比 This refers to the rack and pinion transmission ratio in an electric power steering system.

[0052] Step S500, determining a target steering wheel angle value according to the steering wheel center reference value and the initial steering wheel angle value, and sending the target steering wheel angle value to the bus.

[0053] Specifically, after the initial steering wheel angle value is compensated based on the steering wheel center reference value, the target steering wheel angle value obtained is essentially the deviation of the preset rotor center information relative to the vehicle center, which is equivalent to measuring the current steering wheel angle with a more accurate preset rotor center information, so that the output target steering wheel angle value is more accurate. After sending the target steering wheel angle value to the bus, it can be used by the control system that needs the target steering wheel angle value, which can improve the control accuracy of the corresponding control system.

[0054] It can be understood that the calculation of the target steering wheel angle value can be obtained by using a formula with the steering wheel center reference value and the initial steering wheel angle value, or by judging the steering wheel center reference value to select whether to calculate the initial steering wheel angle value by setting a formula.

[0055] The present application obtains the steering wheel center reference value which can represent the deviation of the preset rotor center information when the vehicle is in a straight running state, and obtains the target steering wheel angle value by modifying and compensating the initial measured initial steering wheel angle value through the judgment of the steering wheel center reference value when sending the real-time steering wheel angle information. The more accurate target steering wheel angle value is sent to the bus as the real-time steering wheel angle information to provide more accurate angle signal of the vehicle in real time. The present application can improve the deviation of the steering wheel center in the development and after-sales process of the vehicle, save maintenance cost and improve efficiency.

[0056] In some embodiments, in step S100, obtaining the preset rotor center information of the motor includes: obtaining initial center calibration information of a TAS sensor, and determining the preset rotor center information according to the initial center calibration information, wherein the TAS sensor is used to detect the steering wheel angle of the vehicle.

[0057] Specifically, since the TAS sensor is generally used to measure the torque and the steering angle of the steering wheel, the TAS sensor is usually calibrated to obtain initial mid-point calibration information, and the conventional EPS system directly calculates the steering angle of the steering wheel through the initial mid-point calibration information and the real-time steering angle signal of the TAS sensor, but this method is not as accurate as the detection and calculation of the rotor position of the motor in the present embodiment. Therefore, the rotor position of the motor is used to detect and calculate the steering angle of the steering wheel in the present application, and the target steering angle value obtained can improve the accuracy. However, since the mid-point of the motor is difficult to calibrate directly, the initial mid-point calibration information of the TAS sensor can be obtained, and the initial mid-point calibration information is unified with the intermediate position of the rotor of the motor, so as to obtain preset rotor mid-point information. The method of the present embodiment can reduce the difficulty of calibrating the intermediate position of the rotor of the motor, so as to facilitate the mid-point calibration of professionals.

[0058] In some embodiments, step S510, in step S500, determining the target steering angle value according to the steering wheel mid-point reference value and the initial steering angle value includes: when the steering wheel mid-point reference value is within the first threshold range, taking the initial steering angle value as the target steering angle value.

[0059] Specifically, the first threshold range is a calibration value within a reasonable range of the zero position, and when the steering wheel mid-point reference value is within the first threshold range, it means that the preset rotor mid-point information has no deviation or has a small deviation within an acceptable range. The EPS system can directly send the initial steering angle value as the target steering angle value without the need for correction and compensation, thereby avoiding excessive correction and compensation of the initial steering angle value.

[0060] In some embodiments, step S520, in step S500, determining the target steering angle value according to the steering wheel mid-point reference value and the initial steering angle value includes: when the steering wheel mid-point reference value is outside the first threshold range, calculating the target steering angle value through the following formula: rAngle SW =fAngle SW -cxC p ; wherein fAngle SW is the initial steering angle value; rAngle SW is the target steering angle value; c is the steering wheel mid-point reference value; and C p is the steering angle mid-point compensation coefficient.

[0061] It should be noted that the steering angle mid-point compensation coefficient can be calibrated through multiple tests.

[0062] Specifically, the second threshold and the third threshold are respectively set as two end values of the first threshold range, and the second threshold is set to be smaller than the third threshold.

[0063] If the steering wheel center reference value is less than or equal to the second threshold value, it indicates that the current preset rotor center information is on the negative side, and when the compensation is corrected:

[0064] When the initial steering wheel angle value is negative, the numerical value of the initial steering wheel angle value is too large, and therefore needs to be corrected by subtracting a certain amount of negative steering wheel center reference value. The numerical value will be smaller after subtracting the negative value, thereby being compensated and corrected;

[0065] When the initial steering wheel angle value is positive, the numerical value of the initial steering wheel angle value is too small, and therefore needs to be corrected by subtracting a certain amount of negative steering wheel center reference value. The numerical value will be larger after subtracting the negative value, thereby being compensated and corrected;

[0066] If the steering wheel center reference value is greater than or equal to the second threshold value, it indicates that the current preset rotor center information is on the positive side, and when the compensation is corrected:

[0067] When the initial steering wheel angle value is positive, the numerical value of the initial steering wheel angle value is too large, and therefore needs to be corrected by subtracting a certain amount of positive steering wheel center reference value. The numerical value will be smaller after subtracting the positive value, thereby being compensated and corrected;

[0068] When the initial steering wheel angle value is negative, the numerical value of the initial steering wheel angle value is too small, and therefore needs to be corrected by subtracting a certain amount of positive steering wheel center reference value. The numerical value will be smaller after subtracting the positive value, thereby being compensated and corrected.

[0069] Therefore, through the above correction and compensation formula, even in the case of a large range of deviation, the initial steering wheel angle value can be stably and appropriately corrected and compensated.

[0070] In some embodiments, the control method for the steering angle center compensation of the electric power steering system further comprises: obtaining a straight driving time duration value when the vehicle is in a straight driving state; and updating the steering wheel center reference value with the current steering wheel center reference value when the straight driving time duration value is greater than or equal to a fourth threshold value.

[0071] Specifically, as long as the vehicle is in a straight-ahead state, the current rotor center information of the motor is obtained, and the corresponding steering wheel center reference value is calculated. If the steering wheel center reference value is always within the first threshold range, the subsequent steps of obtaining the straight-ahead time duration value and the subsequent correction compensation are not needed, and the initial steering wheel rotation angle value can be directly sent as the target steering wheel rotation angle value. When the steering wheel center reference value is outside the first threshold range, the initial steering wheel rotation angle value needs to be corrected and compensated. The steering wheel center reference value required for correction and compensation is obtained from the steering wheel reference value that meets the conditions. When the vehicle is in a straight-ahead state for a certain period of time, the steering wheel center reference value at this time can more stably and accurately represent the deviation of the preset rotor center information, so as to ensure the accuracy of the correction and compensation.

[0072] In some embodiments, the control method for the steering angle center compensation of the electric power steering system further includes: obtaining a target steering wheel rotation angle value; and controlling the motor to assist the steering wheel rotation according to the target steering wheel rotation angle value.

[0073] Specifically, a more accurate target steering wheel rotation angle value is used to determine the current steering wheel rotation angle, accurately grasp the actual situation of the steering wheel, and assist the steering wheel to realize the functions of steering return, vehicle deviation control, ADAS horizontal request, etc. according to the actual situation of the steering wheel, thereby improving the driving performance of the vehicle.

[0074] In some embodiments, the control method for the steering angle center compensation of the electric power steering system further includes: when the following conditions are met simultaneously, it is determined that the vehicle is in a straight-ahead state: the vehicle speed is not less than a fifth threshold value; the wheel speed difference between the left front wheel and the right front wheel of the vehicle is less than or equal to a sixth threshold value; the difference between the sum of the left front wheel speed and the right rear wheel speed and the sum of the right front wheel speed and the left rear wheel speed of the vehicle is not more than a seventh threshold value; the yaw rate of the vehicle is not more than an eighth threshold value; and the steering wheel torque value of the vehicle is not more than a ninth threshold value.

[0075] Specifically, when the vehicle is traveling at a certain speed, by judging that the wheel speed difference between the left front wheel and the right front wheel of the vehicle, the difference between the sum of the left front wheel speed and the right rear wheel speed and the sum of the right front wheel speed and the left rear wheel speed, i.e. the difference between the wheel speeds of the two diagonal wheels, the yaw rate of the vehicle, and the steering wheel torque are all within the preset range, it can be determined that the vehicle is in a straight-ahead state.

[0076] In some embodiments, as shown in FIG. 3, in some embodiments of the present application, a control method for the steering angle center compensation of the electric power steering system includes the following steps:

[0077] First, the center of the motor is calibrated by the center calibration of the TAS sensor to obtain the preset rotor center information.

[0078] The vehicle driving information is acquired to determine whether the vehicle is in a straight driving state, and the rotor angle position information of the motor is acquired by a sensor, and the initial steering wheel angle value is calculated according to the rotor angle position information;

[0079] When the vehicle is in the straight driving state, the initial steering wheel angle value at this time is the steering wheel center reference value;

[0080] When the steering wheel center reference value is in the first threshold range, the initial steering wheel angle value is sent, and the angle output is used for related functions.

[0081] When the steering wheel center reference value is out of the first threshold range, the target steering wheel angle value is obtained by compensation correction, and the target steering wheel angle value is sent to the bus, and the angle output is used for related functions.

[0082] In addition, when the steering wheel center reference value is out of the first threshold range and the duration of the vehicle in the straight driving state reaches or exceeds the fourth threshold, the angle center self-learning and center updating are triggered, that is, the current steering wheel center reference value is used to update the center steering wheel actual value in the correction compensation formula.

[0083] It should be noted that the control method of the electric power steering system angle center compensation provided in the application can be used in related vehicle control systems to process data.

[0084] From the above description of the embodiments, those skilled in the art can clearly understand that the method according to the above embodiments can be realized by means of software and the necessary general hardware platform, and of course, it can also be realized by hardware. Based on such understanding, the technical solutions of the 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), and includes a plurality of instructions for causing a terminal device (which can be a mobile phone, a computer, a server, or a network device) to execute the method described in each embodiment of the application.

[0085] In the present embodiment, a control device for electric power steering system angle center compensation is also provided, which is used to implement the above embodiments and embodiments, and has been described above. As used below, the term "module" is a combination of software and / or hardware that can implement a predetermined function. Although the device described in the following embodiments is realized by software, the realization of hardware, or the combination of software and hardware is also possible and is conceived.

[0086] As shown in FIG. 4, a control device for electric power steering system angle center compensation includes:

[0087] The acquisition module 700 is specifically configured to execute steps S100, S200 and S400 of the control method in the foregoing embodiments: acquiring preset rotor center position information of the motor; acquiring rotor rotation angle position information of the motor as current rotor center position information when the vehicle is in a straight running state; and acquiring rotor rotation angle position information of the motor.

[0088] The processing module 800 is specifically configured to execute steps S300 and S500 of the control method in the foregoing embodiments: calculating a steering wheel center reference value according to the preset rotor center position information and the current rotor center position information, the steering wheel center reference value being used to represent an angle value of the steering wheel deviating from a center position when the vehicle is in the straight running state; calculating an initial steering wheel rotation angle value according to the preset rotor center position information and the rotor rotation angle position information; and determining a target steering wheel rotation angle value according to the steering wheel center reference value and the initial steering wheel rotation angle value, and sending the target steering wheel rotation angle value to a bus.

[0089] In some embodiments, the acquisition module 700 is further configured to acquire a straight running time duration value of the vehicle in the straight running state.

[0090] In some embodiments, the processing module 800 is further configured to: when the steering wheel center reference value is within a first threshold range, take the initial steering wheel rotation angle value as the target steering wheel rotation angle value.

[0091] In some embodiments, the processing module 800 is further configured to: when the steering wheel center reference value is outside the first threshold range, calculate the target steering wheel rotation angle value by the following formula: rAngle SW = fAngle SW - c x C p ; wherein fAngle SW is the initial steering wheel rotation angle value; rAngle SW is the target steering wheel rotation angle value; c is the steering wheel center reference value; and C p is a rotation angle center compensation coefficient.

[0092] In some embodiments, the processing module 800 is further configured to: when the straight running time duration value is greater than or equal to a fourth threshold value, update the steering wheel center reference value with a current steering wheel center reference value.

[0093] In some embodiments, the processing module 800 is further configured to: determine a rotor rotation angle value according to the preset rotor center position information and the rotor rotation angle position information; and calculate the initial steering wheel rotation angle value by the following formula: fAngle SW = Angle motor / (S 减速比 * I 传动比 ); wherein fAngle SW is the initial steering wheel rotation angle value; Angle motor is the rotor rotation angle value; S减速比 is a reduction gear ratio in an electric power steering system; 传动比 is a rack and pinion gear ratio in an electric power steering system.

[0094] In some embodiments, the processing module 800 is further configured to determine that the vehicle is in the straight driving state when the following conditions are met simultaneously: the vehicle speed of the vehicle is not less than a fifth threshold value; the wheel speed difference between the left front wheel and the right front wheel of the vehicle is less than or equal to a sixth threshold value; the difference between the sum of the left front wheel speed and the right rear wheel speed and the sum of the right front wheel speed and the left rear wheel speed of the vehicle does not exceed a seventh threshold value; the yaw angular velocity of the vehicle does not exceed an eighth threshold value; and the steering wheel torque value of the vehicle does not exceed a ninth threshold value.

[0095] In some embodiments, the control device for electric power steering system steering angle center compensation further comprises a TAS sensor, the TAS sensor being configured to: obtain initial center calibration information of the TAS sensor, and determine preset rotor center information according to the initial center calibration information, wherein the TAS sensor is configured to detect the steering wheel steering angle of the vehicle.

[0096] In some embodiments, the control device for electric power steering system steering angle center compensation further comprises a function logic calculation module, the function logic calculation module being configured to obtain a target steering wheel steering angle value, and control the motor to assist the steering wheel to rotate according to the target steering wheel steering angle value.

[0097] As shown in FIG. 5, in some embodiments of the present application, a control device for electric power steering system steering angle center compensation comprises:

[0098] a TAS sensor configured to send initial center calibration information and steering wheel torque;

[0099] a vehicle signal processing module configured to obtain vehicle speed, wheel speed of four wheels, and vehicle yaw angular velocity;

[0100] a steering angle center processing module configured to determine preset rotor center information of the motor according to the initial center calibration information, obtain motor rotor steering angle position information and calculate an initial steering wheel steering angle value, determine a target steering wheel steering angle value according to the initial steering wheel steering angle value and a steering wheel center reference value, and send the target steering wheel steering angle value to the function logic calculation module;

[0101] a steering angle center judgment module configured to obtain vehicle signal processing module data and steering wheel torque to determine whether the vehicle is in a straight driving state, and obtain the initial steering wheel steering angle value as the steering wheel center reference value from the steering angle center processing module in the straight driving state, and send the steering wheel center reference value to the steering angle center self-learning and compensation module.

[0102] The corner median self-learning and compensation module is configured to send the steering wheel median reference value to the corner median processing module for calculation when the steering wheel median reference value is outside a first threshold range and the duration of the vehicle in the straight running state reaches a fourth threshold.

[0103] The function logic calculation module is configured to obtain the target steering wheel corner value and control the motor to assist the steering wheel to rotate.

[0104] The motor is configured to send the motor rotor corner position information.

[0105] Optionally, specific examples in the present embodiment can refer to the examples described in the above embodiments and optional implementation manners, and the present embodiment will not be described here again.

[0106] The present embodiment also provides a vehicle comprising a memory and a processor, the memory storing a computer program, and the processor being configured to run the computer program to perform the control method of the electric power-assisted steering system corner median compensation according to any one of the above embodiments.

[0107] Optionally, in the present embodiment, the processor in the above vehicle can be configured to run the computer program to perform the steps of the control method in the above embodiments.

[0108] Step S100: obtaining preset rotor median information of the motor;

[0109] Step S200: obtaining rotor corner position information of the motor as current rotor median information when the vehicle is in the straight running state;

[0110] Step S300: calculating a steering wheel median reference value according to the preset rotor median information and the current rotor median information, the steering wheel median reference value being used to represent an angle value of the steering wheel deviating from the median position when the vehicle is in the straight running state;

[0111] Step S400: obtaining the rotor corner position information of the motor, and calculating an initial steering wheel corner value according to the preset rotor median information and the rotor corner position information;

[0112] Step S500: determining a target steering wheel corner value according to the steering wheel median reference value and the initial steering wheel corner value, and sending the target steering wheel corner value to the bus.

[0113] Optionally, specific examples in the present embodiment can refer to the examples described in the above embodiments and optional implementation manners, and the present embodiment will not be described here again.

[0114] The embodiment of the present application further provides a storage medium, wherein the storage medium stores a computer program, and the computer program is configured to execute the control method of the electric power steering system mid-position compensation when running on a computer or a processor.

[0115] Optionally, in the embodiment, the computer program can be configured to store the computer program for executing the control method steps in the foregoing embodiments.

[0116] Step S100: obtaining preset rotor mid-position information of the motor;

[0117] Step S200: obtaining rotor rotation position information of the motor as current rotor mid-position information when the vehicle is in a straight driving state.

[0118] Step S300: calculating a steering wheel mid-position reference value according to the preset rotor mid-position information and the current rotor mid-position information, wherein the steering wheel mid-position reference value is used to represent an angle value of the steering wheel deviating from a mid-position in the straight driving state of the vehicle.

[0119] Step S400: obtaining rotor rotation position information of the motor, and calculating an initial steering wheel rotation angle value according to the preset rotor mid-position information and the rotor rotation position information.

[0120] Step S500: determining a target steering wheel rotation angle value according to the steering wheel mid-position reference value and the initial steering wheel rotation angle value, and sending the target steering wheel rotation angle value to a bus.

[0121] Optionally, the specific examples in the embodiment can refer to the examples described in the foregoing embodiments and optional implementation manners, and the embodiment will not be described herein.

[0122] In the foregoing embodiments of the present application, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0123] In some embodiments of the present application, it should be understood that the disclosed technology can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the modules can be a logical function division, and actual implementation can have another division manner, for example, a plurality of modules or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed ones can be through some interfaces, indirect coupling or communication connection between the modules or components, which can be electrical or other forms.

[0124] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules, i.e., may be located in one place, or may be distributed to multiple modules. Part or all of the modules can be selected as needed to achieve the purpose of the embodiment.

[0125] In addition, the functional modules in each embodiment of the present application can be integrated into one processing module, or each module can exist physically alone, or two or more modules can be integrated into one module. The integrated module can be realized in the form of hardware or in the form of a software functional module.

[0126] The integrated module, if realized in the form of a software functional module and sold or used as an independent product, can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application, essentially or the part that contributes to the prior art, or all or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The foregoing storage medium includes: a U disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a mobile hard disk, a magnetic disk or an optical disk, and various program code storage media.

[0127] The above is only some embodiments of the present application, and it should be pointed out that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should be considered as the protection scope of the present application.

Claims

1. A control method for mid-position compensation of steering angle in an electric power steering system, applied to an electric power steering system with a motor, comprising: Obtain the preset rotor center position information of the motor; When the vehicle is traveling straight, the rotor angle position information of the motor is obtained, and the rotor angle position information is used as the current rotor center position information; The steering wheel center reference value is calculated based on the preset rotor center position information and the current rotor center position information. The steering wheel center reference value is used to represent the angle value of the steering wheel deviating from the center position when the vehicle is in a straight driving state. Obtain the rotor angle position information of the motor, and calculate the initial steering wheel angle value based on the preset rotor center position information and the rotor angle position information; The target steering wheel angle value is determined based on the steering wheel center reference value and the initial steering wheel angle value, and the target steering wheel angle value is sent to the bus.

2. The control method for center-position compensation of steering angle in an electric power steering system according to claim 1, wherein, The process of obtaining the preset rotor midpoint information of the motor includes: The initial center calibration information of the TAS sensor is obtained, and the preset rotor center information is determined based on the initial center calibration information, wherein the TAS sensor is used to detect the steering wheel angle of the vehicle.

3. The control method for center-position compensation of steering angle in an electric power steering system according to claim 1, wherein, Determining the target steering wheel angle value based on the steering wheel center reference value and the initial steering wheel angle value includes: When the steering wheel center reference value is within the first threshold range, the initial steering wheel angle value is used as the target steering wheel angle value.

4. The control method for center-position compensation of steering angle in an electric power steering system according to claim 1, wherein, Determining the target steering wheel angle value based on the steering wheel center reference value and the initial steering wheel angle value includes: When the steering wheel center reference value is outside the first threshold range, the target steering wheel angle value is calculated using the following formula: rAngle SW =fAngle SW -c×C p Among them, fAngle SW The initial steering wheel angle value; rAngle SW c is the target steering wheel angle value; c is the steering wheel center reference value; C p This is the median compensation coefficient for the corner.

5. The control method for center position compensation of the steering angle of an electric power steering system according to claim 4 further includes: Obtain the duration value of the straight-ahead travel time of the vehicle; When the straight-ahead time duration is greater than or equal to the fourth threshold, the steering wheel center reference value is updated with the current steering wheel center reference value.

6. The control method for center-position compensation of steering angle in an electric power steering system according to claim 1, wherein, The step of calculating the initial steering wheel angle value based on the preset rotor center position information and the rotor angle position information includes: The rotor angle value is determined based on the preset rotor mid-position information and the rotor angle position information; Calculate the initial steering wheel angle using the following formula: fAngle SW =Angle motor / (S 减速比 *I 传动比 ); where fAngle SW Angle is the initial steering wheel angle value. motor S is the rotor angle value. 减速比 I is the gear ratio of the reduction mechanism in an electric power steering system. 传动比 This refers to the rack and pinion transmission ratio in an electric power steering system.

7. The control method for center position compensation of the steering angle of an electric power steering system according to claim 1 further includes: Obtain the target steering wheel angle value; The motor is controlled to operate according to the target steering wheel angle value to assist the steering wheel rotation.

8. The control method for center position compensation of an electric power steering system according to claim 1 further includes determining that the vehicle is in a straight-moving state when the following conditions are met simultaneously: The vehicle's speed is not less than the fifth threshold. The wheel speed difference between the left front wheel and the right front wheel of the vehicle is less than or equal to the sixth threshold. The difference between the sum of the speeds of the left front wheel and the right rear wheel of the vehicle and the sum of the speeds of the right front wheel and the left rear wheel does not exceed the seventh threshold. The yaw rate of the vehicle does not exceed the eighth threshold. The steering wheel torque value of the vehicle does not exceed the ninth threshold.

9. A device for compensating the steering angle center position of an electric power steering system, comprising: The acquisition module is used to: acquire the preset rotor center position information of the motor; When the vehicle is traveling straight, the rotor angle position information of the motor is obtained as the current rotor center position information; and the rotor angle position information of the motor is obtained. The processing module is configured to: calculate a steering wheel center reference value based on the preset rotor center position information and the current rotor center position information, wherein the steering wheel center reference value represents the angle value of the steering wheel deviating from the center position when the vehicle is in a straight-ahead state; and calculate an initial steering wheel angle value based on the preset rotor center position information and the rotor angle position information. The target steering wheel angle value is determined based on the steering wheel center reference value and the initial steering wheel angle value, and then the target steering wheel angle value is sent to the bus.

10. The device for offset compensation of the steering angle of an electric power steering system according to claim 9, wherein, The acquisition module includes a TAS sensor, which is used to acquire the initial center calibration information of the TAS sensor and determine the preset rotor center information based on the initial center calibration information. The TAS sensor is used to detect the steering wheel angle of the vehicle.

11. The device for compensation of steering angle in an electric power steering system according to claim 9, wherein, The processing module includes a functional logic calculation module, which is used to obtain the target steering wheel angle value and control the motor-assisted steering wheel rotation based on the target steering wheel angle value.

12. A vehicle comprising a memory and a processor, the memory storing a computer program, the processor being configured to run the computer program to perform a control method for angle center compensation of an electric power steering system as described in any one of claims 1 to 8.

13. A storage medium storing a computer program, wherein, The computer program is configured to execute, when running on a computer or processor, a control method for center position compensation of steering angle in an electric power steering system as described in any one of claims 1 to 8.

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