Vehicle steering control method and related device

Abstract

The invention provides a vehicle steering control method and a related device. The method comprises the steps that a rotating speed signal of a motor in a steering system of a vehicle and a vehicle speed signal of the vehicle are obtained; generating a target vibration suppression torque signal based on the rotating speed signal and the vehicle speed signal; the target vibration suppression torque signal is used for adjusting the power-assisted torque of the steering system; synthesizing a second torque signal based on the target vibration suppression torque signal and a first torque signal, the first torque signal being determined based on a torque signal from the target sensor; the target sensor is used for detecting steering wheel torque signals of a vehicle; and controlling the motor to realize power-assisted steering based on the second torque signal. By adopting the embodiment of the invention, the resonance caused by the steering system can be effectively reduced.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a vehicle steering control method and related devices. Background Art

[0002] In a vehicle, due to reasons such as the structure and layout of the vehicle, there will be resonance points in a certain frequency band between the interior and the body. In the vehicle's steering system, since the motor control is not perfect, for example, due to factors such as the deviation and delay of zero current sampling and the motor position sensor (MPS) signal bias, the motor may have order vibration. When order vibration occurs, the steering system becomes an excitation source, causing the steering system to resonate with the vehicle.

[0003] The above resonance is more serious when the vehicle is driving at a low speed or when the vehicle is stationary. For example, when the vehicle is creeping on a road with a low friction coefficient (such as a tile sprinkler road, a slippery epoxy floor road, an indoor underground parking lot or an icy and snowy road, etc.), or when the vehicle enters a maintenance state and the tires are lifted off the ground by a lift, the resonance is more serious. Once the resonance of the vehicle body is aroused, in addition to the violent fluctuations in the steering wheel torque, severe vibrations may also occur in the doors and floor, causing a serious reduction in driving comfort and potential safety hazards. For this reason, how to reduce this resonance is a technical problem that people in this field urgently need to solve. Summary of the invention

[0004] The present application provides a vehicle steering control method and related devices, which can effectively reduce the resonance caused by the steering system, improve the user's driving experience and reduce potential safety hazards.

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

[0006] Acquiring a rotation speed signal of a motor in a steering system of the aforementioned vehicle and a vehicle speed signal of the aforementioned vehicle;

[0007] generating a target vibration suppression torque signal based on the aforementioned rotation speed signal and the aforementioned vehicle speed signal; the aforementioned target vibration suppression torque signal is used to adjust the power assist torque of the aforementioned steering system;

[0008] synthesizing a second torque signal based on the aforementioned target vibration suppression torque signal and a first torque signal, wherein the aforementioned first torque signal is determined based on a torque signal from a target sensor; the aforementioned target sensor is used to detect a steering wheel torque signal of the aforementioned vehicle;

[0009] Based on the second torque signal, the motor is controlled to achieve power steering.

[0010] In a specific implementation, the jitter of the motor speed will be responded by the steering system and then generate forced resonance. Therefore, in the above implementation scheme, the target vibration suppression torque signal is generated by the speed signal of the motor in the steering system and the vehicle speed signal. The target vibration suppression torque signal can be used to synthesize a new torque signal (i.e., the second torque signal) with the feel-related torque signal (i.e., the first torque signal) to achieve the adjustment of the torque of the steering system. Since the resonant main frequency of the whole vehicle including the steering system is not only related to the entire structure and layout, but also can be improved by electrical signals to improve the overall dynamic response. For example, adding a feedback torque related to the speed in the steering controller is equivalent to adding damping to the system. The scheme is to extract the vibration of the motor speed, and actually obtain a signal equivalent to the motor angular acceleration (differential of the motor speed), so the equivalent moment of inertia of the whole system is changed. That is, the resonant main frequency of the whole vehicle including the steering system is adjusted by this scheme. Therefore, the vibration caused by the motor will not cause the resonance of the whole vehicle, thereby achieving the effect of vibration isolation. At this time, the motor speed is relatively stable after vibration isolation, and because the motor speed is determined by the speed input of the steering wheel that controls the steering system, changing the torque will not change the motor speed and will not affect the stability of the first current. Therefore, using the adjusted second torque signal to control the motor to achieve power steering will no longer cause resonance, thereby reducing the resonance of the steering system, improving the user's driving experience and reducing potential safety hazards.

[0011] In a possible implementation, the generating of the target vibration suppression torque signal based on the rotation speed signal and the vehicle speed signal includes:

[0012] acquiring a first vibration suppression torque signal based on the aforementioned speed signal, wherein a frequency of the aforementioned first vibration suppression torque signal includes a resonance frequency of the aforementioned vehicle;

[0013] Obtaining a target gain coefficient based on the aforementioned vehicle speed signal; the aforementioned target gain coefficient is used to adjust the amplitude of the aforementioned first vibration suppression torque signal;

[0014] The target vibration-suppression torque signal is calculated based on the first vibration-suppression torque signal and the target gain coefficient.

[0015] In the above scheme, the target vibration suppression torque signal is obtained by extracting the component with the resonant main frequency from the speed signal and determining the gain coefficient of the component through the vehicle speed signal. In this implementation, the frequency of the target vibration suppression torque signal is the resonant main frequency, so that the signal of the resonant main frequency in the above first torque signal can be suppressed, thereby effectively reducing vibration.

[0016] In a possible implementation, the step of obtaining the first vibration suppression torque signal based on the speed signal includes:

[0017] Extracting a second vibration suppression torque signal from the aforementioned speed signal; the aforementioned second vibration suppression torque signal includes a signal in the aforementioned speed signal having a frequency of the aforementioned resonance frequency;

[0018] The phase of the second vibration suppression torque signal is adjusted to obtain the first vibration suppression torque signal; the phases of the first vibration suppression torque signal and the second vibration suppression torque signal are the same or different.

[0019] In the above scheme, the component with the resonant main frequency in the speed signal is first extracted, and then the phase adjustment is performed to reduce the phase difference with the above-mentioned first torque signal, thereby better suppressing the signal of the resonant main frequency in the first torque signal, thereby effectively reducing vibration.

[0020] In a possible implementation, the adjusting the phase of the second vibration suppression torque signal includes: performing lead compensation on the phase of the second vibration suppression torque signal.

[0021] In the above scheme, phase advance compensation is performed to eliminate phase delay, thereby reducing the phase difference with the above first torque signal, thereby better suppressing the resonant main frequency signal in the first torque signal, and effectively reducing vibration.

[0022] In a possible implementation, the extracting the second vibration suppression torque signal from the speed signal includes:

[0023] The second vibration suppression torque signal is extracted from the rotation speed signal through a resonant oscillator; the amplitude gain of the resonant oscillator at the resonant frequency is 0 dB.

[0024] In the above scheme, a resonant oscillator having an amplitude gain of 0 dB at the above resonance frequency is used, so that the above second vibration suppression torque signal can be extracted from the vehicle speed signal without distortion.

[0025] In a possible implementation, the extracting the second vibration suppression torque signal from the speed signal includes:

[0026] extracting a third vibration suppression torque signal from the aforementioned speed signal through a high-pass filter; the cutoff frequency of the aforementioned high-pass filter is less than the aforementioned resonance frequency;

[0027] extracting a fourth vibration suppression torque signal from the third vibration suppression torque signal through a low-pass filter; the cut-off frequency of the low-pass filter is greater than the resonance frequency; the frequency of the fourth vibration suppression torque signal includes the resonance frequency;

[0028] The amplitude of the fourth vibration suppression torque signal is adjusted by the amplitude adjustment module to obtain the second vibration suppression torque signal; the amplitude gain of the second vibration suppression torque signal at the resonance frequency is 0 dB.

[0029] In the above scheme, a high-pass filter, a low-pass filter and an amplitude adjustment module can be combined, and the amplitude adjustment module is designed to adjust the amplitude gain of the fourth vibration suppression torque signal to 0 dB at the resonance frequency to obtain the second vibration suppression torque signal, so as to extract the second vibration suppression torque signal from the vehicle speed signal without distortion.

[0030] In a possible implementation, the acquiring the target gain coefficient based on the vehicle speed signal includes: searching for the target gain coefficient in a negative gain relationship table based on the vehicle speed signal; and the gain coefficient in the negative gain relationship table is less than zero.

[0031] In the above scheme, acceleration feedback is constructed through the negative gain coefficient, which improves the rotational inertia of the system, thereby changing the frequency response of the entire vehicle system, thereby changing the resonant frequency of the vehicle to suppress resonance.

[0032] In a possible implementation, the gain coefficient in the aforementioned negative gain relationship table increases as the vehicle speed increases.

[0033] In the above scheme, after the vehicle speed increases, it indicates that the vehicle has entered a normal driving state, the steering wheel will not turn too violently, and the resonance caused will also be weakened. By increasing the negative gain coefficient, excessive suppression of torque can be avoided to reduce the impact on the user's steering wheel feel.

[0034] In a possible implementation, the method of obtaining the target gain coefficient based on the vehicle speed signal further includes:

[0035] Based on the aforementioned vehicle speed signal, a negative gain coefficient is searched in a negative gain relationship table; the gain coefficient in the aforementioned negative gain relationship table is less than zero;

[0036] Based on the aforementioned vehicle speed signal, a positive gain coefficient is searched in a positive gain relationship table; the gain coefficient in the aforementioned positive gain relationship table is greater than zero;

[0037] The target gain coefficient is calculated based on the negative gain coefficient and the positive gain coefficient.

[0038] In the above scheme, the target gain coefficient is calculated based on the negative gain coefficient and the positive gain coefficient, and the design scheme of positive gain and negative gain is adopted. On the one hand, the dynamic characteristics under different vehicle speeds are adjustable. On the other hand, the feedback formed by the negative gain and the compensation formed by the positive gain can universally suppress vibration in different control scenarios such as closed loop and open loop.

[0039] In a possible implementation, the gain coefficient in the aforementioned negative gain relationship table increases with the increase of vehicle speed, and the gain coefficient in the aforementioned positive gain relationship table decreases with the increase of vehicle speed.

[0040] In the above scheme, after the vehicle speed increases, it indicates that the vehicle has entered a normal driving state, the steering wheel will not turn too violently, and the resonance caused will also be weakened. By increasing the negative gain coefficient and reducing the positive gain coefficient, excessive torque suppression can be avoided to reduce the impact on the user's steering wheel feel.

[0041] In a possible implementation, the aforementioned target sensor is also used to detect a steering wheel angle signal of the aforementioned vehicle;

[0042] The first torque signal is determined based on a torque signal from a target sensor, including:

[0043] The first torque signal includes a signal obtained by one or more of the following processes based on the torque signal from the target sensor, the vehicle speed signal and the steering wheel angle signal: basic power assist control process, high frequency gain process, phase compensation and damping control process.

[0044] In the above scheme, after the above processing, the user's feeling of using the steering wheel can be optimized and the user experience can be improved.

[0045] In a second aspect, the present application provides a motor controller, which is applied to a steering system of a vehicle, and the motor controller includes:

[0046] An acquisition unit, used to acquire a rotation speed signal of a motor in a steering system of the aforementioned vehicle and a vehicle speed signal of the aforementioned vehicle;

[0047] a resonance suppression processing unit, configured to generate a target vibration suppression torque signal based on the aforementioned rotation speed signal and the aforementioned vehicle speed signal; the aforementioned target vibration suppression torque signal is used to adjust the assist torque of the aforementioned steering system;

[0048] a synthesis unit, configured to synthesize a second torque signal based on the target vibration suppression torque signal and a first torque signal, wherein the first torque signal is determined based on a torque signal from a target sensor; the target sensor is configured to detect a steering wheel torque signal of the vehicle;

[0049] A control unit is used to control the motor to achieve power steering based on the second torque signal.

[0050] In a possible implementation, the resonance suppression processing unit is specifically used to:

[0051] acquiring a first vibration suppression torque signal based on the aforementioned speed signal, wherein a frequency of the aforementioned first vibration suppression torque signal includes a resonance frequency of the aforementioned vehicle;

[0052] Obtaining a target gain coefficient based on the aforementioned vehicle speed signal; the aforementioned target gain coefficient is used to adjust the amplitude of the aforementioned first vibration suppression torque signal;

[0053] The target vibration-suppression torque signal is calculated based on the first vibration-suppression torque signal and the target gain coefficient.

[0054] In a possible implementation, the resonance suppression processing unit is specifically used to:

[0055] Extracting a second vibration suppression torque signal from the aforementioned speed signal; the aforementioned second vibration suppression torque signal includes a signal in the aforementioned speed signal having a frequency of the aforementioned resonance frequency;

[0056] The phase of the second vibration suppression torque signal is adjusted to obtain the first vibration suppression torque signal; the phases of the first vibration suppression torque signal and the second vibration suppression torque signal are the same or different.

[0057] In a possible implementation, the resonance suppression processing unit is specifically used to: perform lead compensation on the phase of the second vibration suppression torque signal.

[0058] In a possible implementation, the resonance suppression processing unit is specifically used to: extract the second vibration suppression torque signal from the speed signal through a resonant oscillator; the amplitude gain of the resonant oscillator at the resonant frequency is 0 dB.

[0059] In a possible implementation, the resonance suppression processing unit is specifically used to:

[0060] extracting a third vibration suppression torque signal from the aforementioned speed signal through a high-pass filter; the cutoff frequency of the aforementioned high-pass filter is less than the aforementioned resonance frequency;

[0061] extracting a fourth vibration suppression torque signal from the third vibration suppression torque signal through a low-pass filter; the cut-off frequency of the low-pass filter is greater than the resonance frequency; the frequency of the fourth vibration suppression torque signal includes the resonance frequency;

[0062] The amplitude of the fourth vibration suppression torque signal is adjusted by the amplitude adjustment module to obtain the second vibration suppression torque signal; the amplitude gain of the second vibration suppression torque signal at the resonance frequency is 0 dB.

[0063] In a possible implementation, the resonance suppression processing unit is specifically used to: search for the target gain coefficient in a negative gain relationship table based on the vehicle speed signal; and the gain coefficient in the negative gain relationship table is less than zero.

[0064] In a possible implementation, the gain coefficient in the aforementioned negative gain relationship table increases as the vehicle speed increases.

[0065] In a possible implementation, the resonance suppression processing unit is specifically used to:

[0066] Based on the aforementioned vehicle speed signal, a negative gain coefficient is searched in a negative gain relationship table; the gain coefficient in the aforementioned negative gain relationship table is less than zero;

[0067] Based on the aforementioned vehicle speed signal, a positive gain coefficient is searched in a positive gain relationship table; the gain coefficient in the aforementioned positive gain relationship table is greater than zero;

[0068] The target gain coefficient is calculated based on the negative gain coefficient and the positive gain coefficient.

[0069] In a possible implementation, the gain coefficient in the aforementioned negative gain relationship table increases with the increase of vehicle speed, and the gain coefficient in the aforementioned positive gain relationship table decreases with the increase of vehicle speed.

[0070] In a possible implementation, the aforementioned target sensor is also used to detect a steering wheel angle signal of the aforementioned vehicle;

[0071] The first torque signal is determined based on a torque signal from a target sensor, including:

[0072] The first torque signal includes a signal obtained by one or more of the following processes based on the torque signal from the target sensor, the vehicle speed signal and the steering wheel angle signal: basic power assist control process, high frequency gain process, phase compensation and damping control process.

[0073] In a third aspect, the present application provides a motor controller, which is applied to a steering system of a vehicle, and includes a processor, a communication interface, and a memory, wherein the communication interface is used to realize data reception and transmission, the memory is used to store computer programs or computer instructions, and the processor is used to execute the computer programs or computer instructions stored in the memory, so that the motor controller performs a method as described in any one of the first aspect and its possible implementation methods.

[0074] In a fourth aspect, the present application provides a steering system, which includes a motor controller as described in any one of the second aspect and its possible implementation methods; or, the steering system includes a motor controller as described in the third aspect.

[0075] In a fifth aspect, the present application provides a vehicle, comprising a steering system as described in the fourth aspect above.

[0076] In a sixth aspect, the present application provides a chip, which is applied to a steering system of a vehicle, wherein the chip includes a processor, a communication interface and a memory, wherein the communication interface is used to realize the reception and transmission of data, the memory is used to store computer programs or computer instructions, and the processor is used to execute the computer programs or computer instructions stored in the memory, so that the chip executes a method as described in any one of the first aspect and its possible implementation methods.

[0077] In a seventh aspect, the present application provides a computer-readable storage medium storing a computer program or computer instructions, wherein the computer program or computer instructions are executed by a processor to implement a method as described in any one of the first aspect and its possible implementation methods.

[0078] In an eighth aspect, the present application provides a computer program product. When the computer program product is executed by a processor, the method as described in any one of the first aspect and its possible implementation methods will be implemented.

[0079] The solutions provided in the second to eighth aspects are used to implement or cooperate with the corresponding methods provided in the first aspect, and therefore can achieve the same or corresponding beneficial effects as the corresponding methods in the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] Figure 1 A schematic diagram of the structure of a steering system provided in an embodiment of the present application;

[0081] Figure 2 A schematic diagram of a method flow chart provided in an embodiment of the present application;

[0082] Figure 3 and Figure 4 A schematic diagram of the structure of a motor controller provided in an embodiment of the present application;

[0083] Figure 5 A schematic diagram of the structure of a resonance suppression processing unit provided in an embodiment of the present application;

[0084] Figure 6 A schematic diagram of a frequency response characteristic curve provided in an embodiment of the present application;

[0085] Figure 7 A schematic diagram of the structure of the signal extraction module provided in the embodiment of the present application;

[0086] Figure 8A schematic diagram of a curve showing the relationship between vehicle speed and gain coefficient provided in an embodiment of the present application;

[0087] Fig. 9 A schematic diagram of the structure of a gain adjustment module provided in an embodiment of the present application;

[0088] Fig.10 A schematic diagram of a curve showing the relationship between vehicle speed and gain coefficient provided in an embodiment of the present application;

[0089] Fig.11 A schematic diagram of the resonance reduction effect provided in an embodiment of the present application;

[0090] Fig.12 A schematic diagram of a virtual structure of a motor controller provided in an embodiment of the present application;

[0091] Fig.13 A schematic diagram of the physical structure of a motor controller provided in an embodiment of the present application. DETAILED DESCRIPTION

[0092] In the embodiment of the present application, "multiple" refers to two or more. In the embodiment of the present application, "and / or" is used to describe the association relationship of the associated objects, indicating three relationships that can exist independently, for example, A and / or B, which can be expressed as: A exists alone, B exists alone, or A and B exist at the same time. The description methods such as "at least one (or at least one) of a1, a2, ... and an" used in the embodiment of the present application include the situation where any one of a1, a2, ... and an exists alone, and also include any combination of any multiple of a1, a2, ... and an, each of which can exist alone; for example, the description method of "at least one of a, b and c" includes the situation where a is alone, b is alone, c is alone, a and b are combined, a and c are combined, b and c are combined, or abc is combined.

[0093] In the various embodiments of the present application, unless otherwise specified or logically conflicting, the terms and / or descriptions between the various embodiments are consistent and can be referenced to each other, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0094] In specific implementation, the steering system of the vehicle becomes an excitation source due to the order vibration of the motor, which causes the steering system to resonate with the vehicle. Once the resonance of the vehicle body is aroused, in addition to the violent fluctuation of the steering wheel torque, severe vibrations may also occur in the doors and floor, causing a serious reduction in driving comfort and posing safety hazards.

[0095] In order to solve the above-mentioned resonance problem, in one possible existing implementation, a feel-related functional module can be used to attenuate vibration. The main solution is to reduce the bandwidth of the steering system so that the system exhibits a rather sluggish dynamic response to attenuate vibration. However, this reduces the power-assistance response of the system, and the entire system exhibits a very sticky feeling, which affects the steering feel of the system and is difficult for users to accept. More importantly, this solution can only attenuate part of the vibration, or reduce the amplitude of the vibration or the duration of the vibration. However, there are always vibrations that can be perceived by the user, which will inevitably greatly reduce the driving experience or bring safety hazards.

[0096] Exemplarily, the above-mentioned hand-feel-related functional module may be, for example, a processing module for optimizing the hand-feel of the steering wheel. The hand-feel-related functional module may include, for example, part or all of the following modules: a basic power-assist module, a high-frequency gain module, a phase compensation module (also referred to as a stability compensation module, etc.), and a damping control module.

[0097] Exemplarily, the basic power assist module can decompose the torque from the steering wheel (which can be obtained by detecting the target sensor) into two components: a high-frequency part and a low-frequency part. Exemplarily, the target sensor can be, for example, a torque angle sensor, which can simultaneously detect the torque signal and the angle signal of the steering wheel. Alternatively, the target sensor can be, for example, a combination of a torque sensor and an angle sensor. Among them, the torque sensor can detect the torque signal of the steering wheel; the angle sensor can detect the angle signal of the steering wheel.

[0098] The high-frequency part is mainly compensated for by the high-frequency hand force through the high-frequency gain module. This module can be regarded as a differential link, which is used to improve the dynamic response of the system, and can also be used to adjust the phase and amplitude gain of the system. The basic power assist can be calculated by the low-frequency part of the steering wheel torque or the full steering wheel torque, which is a key module to achieve flexible steering. The phase compensation module can realize the lead-lag correction of the torque signal to obtain a larger phase margin. The damping control enhances the stability of the system by introducing the steering wheel speed signal (which can be obtained through the target sensor detection).

[0099] For example, the above existing solutions may have some or all of the following defects when solving the above resonance problem: increasing damping, reducing high-frequency hand force compensation, reducing basic power assistance, reducing the amplitude response of stability compensation at low frequencies, and reducing the bandwidth of motor current closed-loop control. This affects the steering feel of the system and is difficult for users to accept.

[0100] In a specific implementation, the above-mentioned hand-feel-related functional modules are not limited to the functional modules listed here. For example, they may also include a return control module, an inertia compensation module, or a friction compensation module, etc. The relevant functional modules are specifically set according to the actual application requirements, and the embodiments of the present application do not limit this.

[0101] Another existing solution to the above resonance problem is to generate a compensation current based on the motor angular velocity signal and the target reference current (the current generated based on the steering torque signal and the vehicle speed signal), and then superimpose the compensation current on the target reference current to obtain the compensated current, and control the motor by the compensated current. However, this solution has the following defects.

[0102] First, the compensation current is superimposed on the reference current. This makes it impossible to suppress the vibration generated when the scheme is applied to the steering system where the reference current is determined by the steering torque signal, the vehicle speed signal and the motor speed signal. For ease of understanding, take the electric power steering system (EPS) as an example. This is because, in today's EPS, whether it adopts a surface-mounted magnetic or an embedded rotor solution, in addition to the steering torque signal and the vehicle speed signal, the motor speed signal will also participate in the calculation of the reference current as the basic input of the motor weak magnetic control. In this way, the jitter of the motor speed signal will inevitably bring about the jitter of the reference current. At the same time, the steering wheel hand force signal detected by the target sensor is also jittering. Although the relationship between the two jitters is a forced resonance, there is a phase difference between the motor speed signal and the steering torque signal. As a result, the reference current calculated by using these two signals as inputs must have a phase difference with the motor speed signal and the steering torque signal. The motor speed signal is the above-mentioned motor angular velocity signal, so the calculated reference current also has a phase difference with the motor angular velocity signal. The above-mentioned compensation current is generated based on the motor angular velocity signal, so there must be a phase difference between the reference current and the compensation current, and the phase difference is uncontrollable. In this case, if the reference current and the compensation current are superimposed, the signal component causing the resonance cannot be eliminated well due to the existence of the phase difference, and may even be enhanced. Therefore, controlling the motor based on the compensated current obtained after the superposition cannot effectively eliminate the resonance, and may even enhance the resonance. In addition, when this scheme generates the compensation current, it is necessary to consider the vibration amplitude, which may not be thorough in compensation.

[0103] Secondly, the above scheme has poor application effect in embedded systems (embedded systems are composed of hardware and software and are systems that can operate independently). According to the embedded calculation process, the motor angular velocity signal used to calculate the compensation current is generated after the steering execution of the vibration of the previous cycle. The compensation component extracted during the vibration process of the previous cycle is then applied to the current cycle, which inevitably has a phase delay, resulting in incomplete compensation.

[0104] Based on the above analysis, the existing schemes for eliminating resonance have the problem of incomplete compensation and even the possibility of enhancing resonance. Based on this, the embodiment of the present application provides a vehicle steering control method and related devices. It can effectively reduce the resonance caused by the steering system, improve the user's driving experience and reduce potential safety hazards. The following is an exemplary introduction to the scheme of the embodiment of the present application.

[0105] First, the steering system applicable to the embodiment of the present application is introduced as an example. The main function of the steering system is to change or maintain the direction of a vehicle that is moving or reversing. In the case of wheeled vehicles, the method for achieving vehicle steering is that the driver uses a steering mechanism to deflect the wheels (steering wheels) on the steering axle (e.g., the front axle) of the vehicle by a certain angle relative to the longitudinal axis of the vehicle. When the vehicle is traveling in a straight line, the steering wheel is often also affected by the lateral interference force of the road surface, and automatically deflects to change the direction of travel. The driver can also use the steering mechanism to deflect the steering wheel in the opposite direction, thereby restoring the original direction of travel of the vehicle. This mechanism for changing or restoring the direction of travel of the vehicle is called a vehicle steering system (steering system for short).

[0106] Steering systems can include hydraulic power steering (HPS), electro hydraulic power steering (EHPS), electric power steering (EPS), and steering by wire (SBW). Figure 1 The structure of the steering system is described by way of example.

[0107] Figure 1 FIG. 1 is a schematic diagram of the structure of EPS. It can be seen that EPS includes components such as a steering wheel 101, a steering shaft 102, a target sensor 103, a motor controller 104, a speed reduction mechanism 105, a clutch 106, a motor 107, a steering gear 108, a steering tie rod 109 and a wheel 110.

[0108] Exemplarily, the steering wheel 101 is mechanically connected to the steering shaft 102. The steering shaft 102 may, for example, include multiple sections for easy installation. A target sensor 103 and a speed reduction mechanism 105 are mounted on the steering shaft 102. The target sensor 103 is electrically connected to the motor controller 104. The speed reduction mechanism 105 is electrically connected to the clutch 106. The clutch 106 is electrically connected to the motor controller 104 and the motor 107. The motor 107 is electrically connected to the motor controller 104. The steering shaft 102 is also mechanically connected to a steering gear 108. The steering gear 108 is mechanically connected to the wheel 110 via a steering tie rod 109. The working principle of EPS is exemplarily described below.

[0109] Exemplarily, the driver can rotate the steering wheel 101. The rotational movement of the steering wheel 101 is transmitted to the steering gear 108 through the steering shaft 102. The steering gear 108 can pull the steering rod 109 to drive the wheel 110 to rotate a specified angle. In addition, the motor 107 can further assist the movement of the steering rod 109 according to the control instruction of the motor controller 104. Exemplarily, the target sensor 103 can detect the rotation torque and the angle from the steering wheel 101, and convert the detected rotation torque into a torque signal and the angle into an angle signal and send it to the motor controller 104. The motor controller 104 can generate a motor control instruction based on the torque signal, the vehicle speed signal, and the motor speed signal. Then, the motor control instruction is sent to the motor 107. The motor 107 can transmit the power torque to the steering gear 108 based on the motor control instruction to control the steering power strength. The clutch 106 is used to ensure that the electric power assist works within a predetermined range. When the vehicle speed and current exceed the specified maximum value or the steering system fails, the clutch 106 automatically cuts off the motor power and restores manual control steering. The speed reduction mechanism 105 is used to increase the torque transmitted from the motor to the steering gear 108 .

[0110] Exemplarily, the vehicle speed signal input to the motor controller 104 may be, for example, from a vehicle speed sensor or from the controller area network (CAN) of the vehicle. The motor speed signal input to the motor controller 104 may be, for example, from a motor position sensor (MPS) or other sensors that can detect the motor speed. Alternatively, the motor speed signal may be, for example, a signal obtained by indirectly calculating a signal from a sensor such as an MPS. Exemplarily, the indirect solution may be, for example, differentiating the motor mechanical angle collected by the MPS, or extracting the speed information by using a Kalman filter. The vehicle speed signal and motor speed signal described later are similar and will not be described in detail.

[0111] It should be understood that the above introduction to the steering system is merely an example and does not constitute a limitation to the embodiments of the present application.

[0112] For example, the vehicle steering control method provided in the embodiment of the present application can be implemented by the motor controller in the above-mentioned steering system. Figure 2 The vehicle steering control method provided in the embodiment of the present application may include but is not limited to the following steps:

[0113] S201, obtaining a rotation speed signal of a motor in a steering system of the vehicle and a vehicle speed signal of the vehicle.

[0114] S202: Generate a target vibration suppression torque signal based on the rotation speed signal and the vehicle speed signal; the target vibration suppression torque signal is used to adjust the power assist torque of the steering system.

[0115] S203, synthesizing a second torque signal based on the target vibration suppression torque signal and a first torque signal, wherein the first torque signal is determined based on a torque signal from a target sensor; the target sensor is used to detect a steering wheel torque signal of the vehicle.

[0116] S204: Control the motor to achieve power steering based on the second torque signal.

[0117] For ease of understanding, the following Figure 3 The schematic diagram of the structure of the motor controller 200 is used to exemplarily introduce the implementation process of the above method. Figure 1 The motor controller 104 is shown in an EPS, or may be a motor controller in another type of steering system.

[0118] exist Figure 3 As can be seen in FIG. 2 , the motor controller 200 may include a resonance suppression processing unit 210, a hand-feel related function module 220, a torque superposition unit 230, a current calculation unit 240, a subtraction unit 250 and a motor drive unit 260. The functions of each module are exemplarily described below.

[0119] Exemplarily, the resonance suppression processing unit 210 may take the motor speed signal and the vehicle speed signal as inputs. And calculate the target vibration suppression torque signal based on the motor speed signal and the vehicle speed signal. The target vibration suppression torque signal may be used to adjust the torque of the steering system. Then, the resonance suppression processing unit 210 may output the calculated target vibration suppression torque signal to the torque superposition unit 230.

[0120] In addition, the above-mentioned feel-related functional module 220 can take the target sensor signal and the vehicle speed signal as input. The target sensor signal includes a torque signal from the target sensor. Optionally, the target sensor signal also includes a steering wheel angle signal from the target sensor. Based on the target sensor signal and the vehicle speed signal, the feel-related functional module 220 can calculate a feel-related power-assist torque signal (which can be referred to as the first torque signal). Based on the previous introduction, it can be seen that the feel-related functional module 220 can include multiple functional modules. The first torque signal may include the torque signals output by the multiple functional modules. For ease of understanding, please refer to the exemplary Figure 4 .

[0121] exist Figure 4 It can be seen that the hand-feel related functional module 220 may include a basic power assist module 2201, a high-frequency gain module 2202, a phase compensation module 2203 and a damping control module 2204. For the specific functional description of these modules, please refer to the above introduction and will not be repeated here. It can be seen that after the above-mentioned target sensor signal and vehicle speed signal are input into the hand-feel related functional module 220, the signal processed by the basic power assist module 2201 and the high-frequency gain module 2202 can output a torque signal (referred to as torque signal A) after being processed by the phase compensation module 2203. In addition, after being processed by the damping control module 2204, a torque signal (referred to as torque signal B) can be output. Then, the above-mentioned first torque signal includes the torque signal A and the torque signal B.

[0122] Understandably, Figure 4 The structure of the hand feeling related functional module 220 shown is only an example and is not enough to limit the embodiment of the present application. In a specific implementation, the hand feeling related functional module 220 can include more or fewer functional modules, which can be determined according to actual application needs, and the embodiment of the present application does not limit this.

[0123] After the hand feel-related functional module 220 calculates the first torque signal, it can output the first torque signal to the torque superposition unit 230 .

[0124] After the torque superposition unit 230 obtains the target vibration suppression torque signal and the first torque signal, it can synthesize a target torque signal (which can be referred to as the second torque signal) based on the target vibration suppression torque signal and the first torque signal. Exemplarily, the target vibration suppression torque signal and the first torque signal can be directly superimposed to obtain the second torque signal. Or, exemplarily, the target vibration suppression torque signal and the first torque signal can be preprocessed (for example, filtering to reduce noise, etc.) respectively. Then, the two preprocessed signals are superimposed to obtain the second torque signal. It can be understood that this is only an example and does not constitute a limitation on the embodiments of the present application.

[0125] After the torque superposition unit 230 synthesizes the second torque signal, the second torque signal can be output to the current calculation unit 240. The current calculation unit 240 calculates the first current based on the second torque signal and the input vehicle speed signal and the motor speed signal. Alternatively, the current calculation unit 240 calculates the first current based on the second torque signal and the input vehicle speed signal, that is, the motor speed signal does not participate in the calculation of the first current. Alternatively, the current calculation unit 240 calculates the first current based on the second torque signal, the input vehicle speed signal, and parameters such as the steering wheel steering angle. It can be understood that this is only an example and does not constitute a limitation to the embodiments of the present application.

[0126] The first current is output to the subtraction unit 250 and subtracted from the feedback current to obtain the second current. The feedback current is the current output by the motor drive unit 260 for controlling the motor. The second current is input to the motor drive unit 260. The motor drive unit 260 can output a three-phase control voltage and current to the motor 270 based on the second current. This is used to control the motor 270 to achieve power steering.

[0127] Based on the previous introduction, it can be known that the jitter of the motor speed will be responded by the steering system and then generate forced resonance. Therefore, in the above implementation scheme, the target vibration suppression torque signal is generated by the speed signal of the motor in the steering system and the vehicle speed signal. The target vibration suppression torque signal can be used to synthesize a new torque signal (i.e., the second torque signal) with the feel-related torque signal (i.e., the first torque signal) to achieve the adjustment of the torque of the steering system. Since the resonant main frequency of the whole vehicle including the steering system is not only related to the entire structure and layout, but also can be improved by electrical signals to improve the overall dynamic response. For example, adding a feedback torque related to the speed in the steering controller is equivalent to adding damping to the system. The scheme is to extract the vibration of the motor speed, and actually obtain a signal equivalent to the motor angular acceleration (differential of the motor speed), so the equivalent moment of inertia of the whole system is changed. That is, the resonant main frequency of the whole vehicle including the steering system is adjusted by this scheme. Therefore, the vibration caused by the motor will not cause the resonance of the whole vehicle, thereby achieving the effect of vibration isolation. At this time, the motor speed is relatively stable after vibration isolation, and because the motor speed is determined by the speed input of the steering wheel that controls the steering system, changing the torque will not change the motor speed and will not affect the stability of the first current. Therefore, using the adjusted second torque signal to control the motor to achieve power steering will no longer cause resonance, thereby reducing the resonance of the steering system, improving the user's driving experience and reducing potential safety hazards.

[0128] In a possible implementation, the resonance suppression processing unit 210 may calculate the target vibration suppression torque signal based on the motor speed signal and the vehicle speed signal, which may include the following steps: obtaining a first vibration suppression torque signal based on the motor speed signal, obtaining a target gain coefficient based on the vehicle speed signal, and then generating the target vibration suppression torque signal based on the first vibration suppression torque signal and the target gain coefficient.

[0129] Among them, the above-mentioned target gain coefficient can be used to adjust the amplitude of the above-mentioned first vibration suppression torque signal. The frequency of the first vibration suppression torque signal includes the resonant frequency of the vehicle including the steering system. Exemplarily, the first vibration suppression torque signal has the same signal frequency as the target speed signal, and has a different or the same phase as the target speed signal. The signal frequency is usually the resonant frequency of the vehicle including the steering system. Exemplarily, the resonant frequency is pre-tested, that is, the resonance is not allowed to occur without using the scheme, the steering wheel torque signal is collected, the frequency domain characteristics of the signal are analyzed, and the frequency at which the energy is concentrated is found to be the resonant frequency. The value of the resonant frequency can be, for example, between 5Hz and 50Hz. In particular, if the vehicle belongs to a new energy vehicle, the value of the resonant frequency can be, for example, between 20Hz and 35Hz. It can be understood that the value of the resonant frequency described here is only an example and does not constitute a limitation on the embodiments of the present application. In a specific implementation, the resonant frequency can also be, for example, other values, and the embodiments of the present application are not limited to this.

[0130] To facilitate understanding of the above implementation, please refer to Figure 5 . Figure 5 The structural diagram of the resonance suppression processing unit 210 is exemplarily shown. It can be seen that the resonance suppression processing unit 210 may include a signal extraction module 2101, a phase adjustment module 2102, a gain adjustment module 2103 and a multiplication module 2104. The functions of each module are exemplarily introduced below.

[0131] Exemplarily, the signal extraction module 2101 takes the motor speed signal as input and extracts the characteristic signal from the motor speed signal. Then, the characteristic signal can be input into the phase adjustment module 2102. After the phase adjustment module 2102 performs phase compensation on the characteristic signal, it outputs the first vibration suppression torque signal after phase compensation. The gain adjustment module 2103 takes the vehicle speed signal as input and can obtain the target gain coefficient based on the vehicle speed signal. The first vibration suppression torque signal and the target gain coefficient are input into the multiplication module 2104 and multiplied to obtain the target vibration suppression torque signal.

[0132] The following is an exemplary introduction to the implementation process of extracting characteristic signals by the signal extraction module 2101.

[0133] The frequency of the characteristic signal includes the resonant frequency. Exemplarily, the characteristic signal may include a signal in a preset frequency range. The preset frequency range includes the resonant frequency. That is, the signal extraction module 2101 is used to extract the signal in the preset frequency range from the motor speed signal and filter out the signal outside the preset frequency range. For example, the signal outside the preset frequency range can be rapidly attenuated.

[0134] For example, assuming that the resonance frequency is f0, the preset frequency range may be, for example, f0-f1 to f0+f2. The values ​​of f1 and f2 are set according to actual application requirements, and the present application embodiment does not limit this.

[0135] Exemplarily, in order to extract the above characteristic signal without distortion, that is, to ensure that the amplitude and phase of the extracted characteristic signal do not change as much as possible. In a possible implementation, the characteristic signal can be extracted by a resonant oscillator. That is, the above signal extraction module 2101 can be the resonant oscillator. In order to extract the signal without distortion, the amplitude gain of the resonant oscillator at the above resonant frequency is 0dB. Exemplarily, the frequency response characteristic diagram of the resonant oscillator can be exemplarily referred to as Figure 6 .exist Figure 6 It can be seen that the amplitude frequency response curve takes a value of 0dB at the resonance frequency, and the phase frequency response curve takes a value of 0deg at the resonance frequency. That is, after the motor speed signal is input into the resonant oscillator, the signal with the resonance main frequency in the motor speed signal can be output without distortion. Figure 6 It can also be seen that the value of the amplitude-frequency response curve in the preset frequency range is also close to 0dB, and the value of the phase-frequency response curve in the preset frequency range is also close to 0deg. Therefore, the signals in the motor speed signal with frequencies within the preset frequency range can be output well. Other signals will be quickly attenuated and filtered out. The signal output from the resonant oscillator is the above-mentioned characteristic signal (for the convenience of subsequent description, the characteristic signal is called the second vibration suppression torque signal).

[0136] Exemplarily, the resonant oscillator may be a second-order resonant oscillator, a third-order resonant oscillator, a fourth-order resonant oscillator, etc. The embodiment of the present application does not limit the order of the resonant oscillator, which may be selected according to actual application requirements.

[0137] In order to extract the above characteristic signal without distortion, another possible implementation can be exemplified by referring to Figure 7 , the signal extraction module 2101 may include a high-pass filter 21011, a low-pass filter 21012 and an amplitude adjustment module 21013. The cut-off frequency of the high-pass filter 21011 is less than the resonance frequency. Exemplarily, the cut-off frequency of the high-pass filter 21011 may be, for example, f0-f1. The cut-off frequency of the low-pass filter is greater than the resonance frequency. Exemplarily, the cut-off frequency of the low-pass filter 21012 may be, for example, f0+f2. The amplitude adjustment module 21013 is used to adjust the amplitude of the signal so that the amplitude gain of the output characteristic signal at the resonance frequency is 0 dB.

[0138] For example, in the above Figure 7In the signal extraction module 2101 shown, the motor speed signal is first input to the high-pass filter 21011. The high-pass filter 21011 filters the motor speed signal and outputs a third vibration suppression torque signal. Take the cutoff frequency of the high-pass filter 21011 as f0-f1 as an example. Then, after filtering by the high-pass filter 21011, the signal with a frequency less than the cutoff frequency f0-f1 in the motor speed signal is filtered out. The output third vibration suppression torque signal includes the signal with a frequency greater than the cutoff frequency f0-f1 in the motor signal.

[0139] The third vibration suppression torque signal is input to the low-pass filter 21012. The low-pass filter 21012 filters the third vibration suppression torque signal and outputs a fourth vibration suppression torque signal. Take the cutoff frequency of the low-pass filter 21012 as f0+f2 as an example. Then, after filtering by the low-pass filter 21012, the signal with a frequency greater than the cutoff frequency f0+f2 in the third vibration suppression torque signal is filtered out. The output fourth vibration suppression torque signal includes a signal with a frequency less than the cutoff frequency f0+f2 of the third vibration suppression torque signal. That is, the fourth vibration suppression torque signal includes a signal with a frequency between f0-f1 and f0+f2. That is, the fourth vibration suppression torque signal includes a signal in the above-mentioned preset frequency range. Of course, the frequency of the fourth vibration suppression torque signal also includes the above-mentioned resonance frequency.

[0140] The fourth vibration suppression torque signal output by the low-pass filter 21012 is input to the amplitude adjustment module 21013. The amplitude adjustment module 21013 adjusts the amplitude of the fourth vibration suppression torque signal so that the amplitude gain of the output signal (referred to as the fifth vibration suppression torque signal) at the resonance frequency is 0 dB. The fifth vibration suppression torque signal is the characteristic signal output by the signal extraction module 2101.

[0141] The following is an exemplary description of the implementation process of the phase adjustment module 2102 adjusting the phase of the above-mentioned characteristic signal.

[0142] Exemplarily, based on the above description, after the phase adjustment module 2102 performs phase compensation on the above characteristic signal, a first vibration suppression torque signal after phase compensation is output. The phase adjustment module 2102 is a phase advance compensation module, which is used to reduce the phase difference between the target vibration suppression torque signal output by the resonance suppression processing unit 210 and the above first torque signal. Specifically, based on the previous introduction, it can be known that the target vibration suppression torque signal is calculated based on the first vibration suppression torque signal and the target gain coefficient. The target gain coefficient adjusts the amplitude of the first vibration suppression torque signal and does not change the phase of the first vibration suppression torque signal. Therefore, the phase adjustment module 2102 compensates the above characteristic signal to obtain the compensated first vibration suppression torque signal, which is equivalent to phase compensation for the target vibration suppression torque signal. Make the phase difference between the first vibration suppression torque signal and the target vibration suppression torque signal and the above first torque signal less than a preset value. Optionally, even make the phase difference zero. Thereby, the phase difference between the target vibration suppression torque signal and the above first torque signal is reduced. Exemplarily, the phase adjustment module 2102 is used to reduce the phase difference between the target vibration suppression torque signal and the first torque signal at the resonance frequency.

[0143] In a possible implementation, in order to decouple the amplitude of the signal and reduce the influence of phase adjustment on the amplitude, the phase adjustment module 2102 may be a unit gain phase adjustment module. In this implementation, the transfer function of the phase adjustment module 2102 in the continuous domain may be expressed as:

[0144]

[0145] Among them, f0 is the main resonance frequency mentioned above. Constant is the maximum phase compensation angle at the resonant main frequency, The specific value of can be set according to actual application requirements, and the embodiments of the present application do not limit this.

[0146] The transfer function of the phase adjustment module 2102 can be transformed into a discrete domain (i.e., z domain) by bilinear transformation or zero-mapping. For example, bilinear transformation is taken as an example. The discrete domain expression of the transfer function after bilinear transformation is as follows:

[0147]

[0148] Among them, T s is the calculation period of the phase adjustment module 2102.

[0149] It is understandable that the above implementation of the phase adjustment module 2102 is only an example and does not constitute a limitation on the embodiments of the present application. In a specific implementation, the above phase adjustment module 2102 may not be a unit gain phase adjustment module, and may be specifically set according to actual application requirements.

[0150] Exemplarily, the phases of the first vibration suppression torque signal and the characteristic signal may be the same or different. Specifically, although the first vibration suppression torque signal is a signal output after the characteristic signal is phase-compensated by the phase adjustment module 2102. However, in a possible implementation, the compensated phase may be 0 degrees. In this case, the first vibration suppression torque signal and the characteristic signal have the same phase. In a possible implementation, the compensated phase is not 0 degrees. In this case, the first vibration suppression torque signal and the characteristic signal have different phases.

[0151] In the above implementation, the signal extraction module 2101 is first used to extract the component with the resonant main frequency in the motor speed signal, and then phase advance compensation is performed to reduce the phase difference with the above-mentioned first torque signal, thereby better suppressing the signal of the resonant main frequency in the first torque signal, thereby effectively reducing vibration.

[0152] The following is an exemplary description of the implementation process of the gain adjustment module 2103 obtaining the target gain coefficient based on the vehicle speed signal.

[0153] In a possible implementation, the above-mentioned target gain coefficient is a negative gain coefficient. The gain adjustment module 2103 can find the target gain coefficient in the negative gain relationship table based on the vehicle speed signal. The negative gain relationship table pre-stores the corresponding relationship between the vehicle speed and the gain coefficient. The vehicle speed signal has a corresponding relationship with the specific vehicle speed. Therefore, the target gain coefficient can be found in the negative gain relationship table based on the vehicle speed signal. The gain coefficient in the negative gain relationship table is less than zero.

[0154] In a possible implementation, the gain coefficient in the above negative gain relationship table increases with the increase of vehicle speed. For ease of understanding, please refer to Figure 8 . Figure 8 The schematic diagram of the relationship curve between the vehicle speed and the gain coefficient in the negative gain relationship table is shown as an example. Figure 8 It can be seen that the gain coefficient is less than zero, and the gain coefficient increases with the increase of vehicle speed. For example, in the negative gain relationship table, there may be some cases where the gain coefficient decreases when the vehicle speed increases, but this does not affect the trend that the gain coefficient increases with the increase of vehicle speed in the negative gain relationship table. In addition, Figure 8 The curve shown represents this trend and does not constitute a limitation to the embodiments of the present application.

[0155] In this implementation, the negative gain coefficient constructs acceleration feedback, improves the system's moment of inertia, and then changes the frequency response of the entire vehicle system, thereby changing the vehicle's resonant frequency to suppress resonance.

[0156] In another possible implementation, the target gain coefficient is a gain coefficient obtained by combining the negative gain coefficient and the positive gain coefficient. Fig. 9 , shows a schematic diagram of the structure of the gain adjustment module 2103. Fig. 9 As can be seen in FIG. 2 , the gain adjustment module 2103 may include a negative gain adjustment module 21031, a positive gain adjustment module 21032 and an accumulation module 21033. In a specific implementation, the vehicle speed signal may be input into the negative gain adjustment module 21031 and the positive gain adjustment module 21032, respectively.

[0157] The negative gain adjustment module 21031 can find the negative gain coefficient in the negative gain relationship table based on the vehicle speed signal. For specific implementation, reference can be made to the above-mentioned introduction that the target gain coefficient is a negative gain coefficient, which will not be repeated here.

[0158] The positive gain adjustment module 21032 can find the positive gain coefficient in the positive gain relationship table based on the vehicle speed signal. The positive gain relationship table pre-stores the correspondence between the vehicle speed and the gain coefficient. The vehicle speed signal has a correspondence with the specific vehicle speed. Therefore, the target gain coefficient can be found in the positive gain relationship table based on the vehicle speed signal. The gain coefficient in the positive gain relationship table is greater than zero.

[0159] In a possible implementation, in the above positive gain relationship table, the gain coefficient decreases as the vehicle speed increases. For ease of understanding, please refer to Fig.10 . Fig.10 The relationship curve diagram between the vehicle speed and the gain coefficient in the positive gain relationship table is shown as an example. Fig.10 It can be seen that the gain coefficient is greater than zero, and the gain coefficient decreases as the vehicle speed increases. For example, in the positive gain relationship table, there may be some cases where the gain coefficient increases with the increase of vehicle speed, but this does not affect the trend of the gain coefficient decreasing with the increase of vehicle speed in the positive gain relationship table. In addition, Fig.10 The curve shown represents this trend and does not constitute a limitation to the embodiments of the present application.

[0160] After the negative gain adjustment module 21031 obtains the negative gain coefficient, it outputs the negative gain coefficient to the accumulation module 21033. After the positive gain adjustment module 21032 obtains the positive gain coefficient, it outputs the positive gain coefficient to the accumulation module 21033. The accumulation module 21033 adds the negative gain coefficient and the positive gain coefficient or performs weighted addition to obtain the target gain coefficient.

[0161] In this implementation, a positive gain and negative gain design is adopted. On the one hand, the dynamic characteristics under different vehicle speeds can be adjusted. On the other hand, the feedback formed by the negative gain and the compensation formed by the positive gain can universally suppress vibrations in different control scenarios such as closed-loop and open-loop.

[0162] In summary, in the above embodiment, the target vibration suppression torque signal is obtained by extracting the component with the resonant main frequency from the motor speed signal, and then determining the gain coefficient of the component through the vehicle speed signal. In this implementation, the frequency of the target vibration suppression torque signal is the resonant main frequency, so that the signal of the resonant main frequency in the above-mentioned first torque signal can be suppressed, thereby effectively reducing the vibration. In addition, the embodiment of the present application does not need to identify the vibration scene, and the vibration characteristic signal can be adaptively collected through the above-mentioned signal extraction module 2101. Reduce the limitations of the implementation of the solution and expand the application scenarios.

[0163] In order to more intuitively understand the effect of eliminating resonance after adopting the embodiment of the present application, it can be exemplified by referring to Fig.11 . For example, the solution of the embodiment of the present application is applied to a redundant EPS for actual vehicle verification. The redundant EPS adopts a surface mounted magnetic rotor, and the weak magnetic control method adopts a solution of introducing motor speed for control. During the actual vehicle verification process, the steering wheel torque signal collected by the steering wheel target sensor can be used to intuitively represent the steering wheel vibration. For example, the collected torque signal is as follows Fig.11 As shown. It can be seen that before the solution of the embodiment of the present application is adopted, the collected torque signal fluctuates greatly, indicating that a violent resonance occurs. After the solution of the embodiment of the present application is adopted, that is, after the target vibration suppression torque is introduced, the fluctuation of the collected torque signal is greatly reduced. And the jitter of the driver's hand force tested is eliminated; at the same time, the subjective body resonance stops.

[0164] It is to be understood that the structure of the above control unit is only for illustration and does not constitute a limitation on the embodiments of the present application. In a specific implementation, the control unit may also include more or fewer functional modules. As long as the steering control method provided by the above embodiment of the present application can be implemented to reduce resonance, it should not be considered to exceed the scope of the present application.

[0165] Each module in the above-mentioned control unit can be implemented by software, hardware, firmware or any combination of the three, and the embodiments of the present application do not limit this. The specific implementation of a function depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application. In addition, the division of the above-mentioned various functional modules is schematic, which is only a logical function division. There may be other division methods in actual implementation, and the embodiments of the present application do not limit this.

[0166] In the case of dividing each functional module according to each function, the embodiment of the present application also provides a motor controller for implementing any of the above methods, for example, a motor controller is provided including a unit (or means) for implementing each step in any of the above methods. For example, please refer to Fig.12 , which is a schematic diagram of the structure of a motor controller 1200 provided in an embodiment of the present application. The motor controller 1200 is applied to a steering system of a vehicle. The motor controller 1200 may be a motor controller described in any embodiment for implementing the above-mentioned vehicle steering control method. The motor controller 1200 may include an acquisition unit 1201, a resonance suppression processing unit 1202, a synthesis unit 1203 and a control unit 1204. Among them:

[0167] The acquisition unit 1201 is used to acquire the rotation speed signal of the motor in the steering system of the aforementioned vehicle and the vehicle speed signal of the aforementioned vehicle. Exemplarily, the acquisition unit 1201 may be a module in the motor controller 1200 that receives the rotation speed signal and the vehicle speed signal.

[0168] The resonance suppression processing unit 1202 is used to generate a target vibration suppression torque signal based on the aforementioned speed signal and the aforementioned vehicle speed signal; the aforementioned target vibration suppression torque signal is used to adjust the power assist torque of the aforementioned steering system. Exemplarily, the resonance suppression processing unit 1202 may be, for example, the resonance suppression processing unit 210 described in the aforementioned method embodiment.

[0169] The synthesis unit 1203 is used to synthesize the second torque signal based on the aforementioned target vibration suppression torque signal and the first torque signal, wherein the aforementioned first torque signal is determined based on the torque signal from the target sensor; the aforementioned target sensor is used to detect the steering wheel torque signal of the aforementioned vehicle. Exemplarily, the synthesis unit 1203 may be, for example, the torque superposition unit 230 described in the aforementioned method embodiment.

[0170] The control unit 1204 is used to control the motor to realize power steering based on the second torque signal. For example, the control unit 1204 may include the current calculation unit 240, the subtraction unit 250 and the motor drive unit 260 described in the above method embodiment.

[0171] In a possible implementation, the resonance suppression processing unit 1202 is specifically used for:

[0172] acquiring a first vibration suppression torque signal based on the aforementioned speed signal, wherein a frequency of the aforementioned first vibration suppression torque signal includes a resonance frequency of the aforementioned vehicle;

[0173] Obtaining a target gain coefficient based on the aforementioned vehicle speed signal; the aforementioned target gain coefficient is used to adjust the amplitude of the aforementioned first vibration suppression torque signal;

[0174] The target vibration-suppression torque signal is calculated based on the first vibration-suppression torque signal and the target gain coefficient.

[0175] In a possible implementation, the resonance suppression processing unit 1202 is specifically used for:

[0176] Extracting a second vibration suppression torque signal from the aforementioned speed signal; the aforementioned second vibration suppression torque signal includes a signal in the aforementioned speed signal having a frequency of the aforementioned resonance frequency;

[0177] The phase of the second vibration suppression torque signal is adjusted to obtain the first vibration suppression torque signal; the phases of the first vibration suppression torque signal and the second vibration suppression torque signal are the same or different.

[0178] In a possible implementation, the resonance suppression processing unit 1202 is specifically used to: perform lead compensation on the phase of the second vibration suppression torque signal.

[0179] In a possible implementation, the resonance suppression processing unit 1202 is specifically used to: extract the second vibration suppression torque signal from the speed signal through a resonant oscillator; the amplitude gain of the resonant oscillator at the resonant frequency is 0 dB.

[0180] In a possible implementation, the resonance suppression processing unit 1202 is specifically used for:

[0181] extracting a third vibration suppression torque signal from the aforementioned speed signal through a high-pass filter; the cutoff frequency of the aforementioned high-pass filter is less than the aforementioned resonance frequency;

[0182] extracting a fourth vibration suppression torque signal from the third vibration suppression torque signal through a low-pass filter; the cut-off frequency of the low-pass filter is greater than the resonance frequency; the frequency of the fourth vibration suppression torque signal includes the resonance frequency;

[0183] The amplitude of the fourth vibration suppression torque signal is adjusted by the amplitude adjustment module to obtain the second vibration suppression torque signal; the amplitude gain of the second vibration suppression torque signal at the resonance frequency is 0 dB.

[0184] In a possible implementation, the resonance suppression processing unit 1202 is specifically used for: searching for the target gain coefficient in a negative gain relationship table based on the vehicle speed signal; and the gain coefficient in the negative gain relationship table is less than zero.

[0185] In a possible implementation, the gain coefficient in the aforementioned negative gain relationship table increases as the vehicle speed increases.

[0186] In a possible implementation, the resonance suppression processing unit 1202 is specifically used for:

[0187] Based on the aforementioned vehicle speed signal, a negative gain coefficient is searched in a negative gain relationship table; the gain coefficient in the aforementioned negative gain relationship table is less than zero;

[0188] Based on the aforementioned vehicle speed signal, a positive gain coefficient is searched in a positive gain relationship table; the gain coefficient in the aforementioned positive gain relationship table is greater than zero;

[0189] The target gain coefficient is calculated based on the negative gain coefficient and the positive gain coefficient.

[0190] In a possible implementation, the gain coefficient in the aforementioned negative gain relationship table increases with the increase of vehicle speed, and the gain coefficient in the aforementioned positive gain relationship table decreases with the increase of vehicle speed.

[0191] In a possible implementation, the aforementioned target sensor is also used to detect a steering wheel angle signal of the aforementioned vehicle;

[0192] The first torque signal is determined based on a torque signal from a target sensor, including:

[0193] The first torque signal includes a signal obtained by one or more of the following processes based on the torque signal from the target sensor, the vehicle speed signal and the steering wheel angle signal: basic power assist control process, high frequency gain process, phase compensation and damping control process.

[0194] Above Fig.12 The specific operation and beneficial effects of each unit in the motor controller 1200 can be found in the above Figures 2 to 9The corresponding descriptions in possible embodiments thereof will not be repeated here.

[0195] For example, see Fig.13 , which is a structural diagram of a possible physical entity of the motor controller provided in this application. Fig.13 The motor controller 1300 shown may be a motor controller for implementing any embodiment of the above-mentioned vehicle steering control method. The motor controller 1300 includes: a processor 1301, a memory 1302, and a communication interface 1303. The processor 1301, the communication interface 1303, and the memory 1302 may be connected to each other or to each other via a bus 1304.

[0196] Exemplarily, the memory 1302 is used to store computer programs and data of the motor controller 1300. The memory 1302 may include, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read only memory (EPROM) or portable read only memory (compact disc read-only memory, CD-ROM), etc.

[0197] The software or program code required for all or part of the functions of the motor controller in the above method embodiment may be stored in the memory 1302 .

[0198] In one possible implementation, if the software or program code required for some functions is stored in the memory 1302, the processor 1301, in addition to calling the program code in the memory 1302 to implement some functions, can also cooperate with other components (such as the communication interface 1303) to jointly complete other functions described in the method embodiment (such as the function of receiving or sending data).

[0199] There may be multiple communication interfaces 1303 for supporting the motor controller 1300 to communicate, such as receiving or sending data.

[0200] Exemplarily, the processor 1301 may be a processor that is a circuit with data processing capabilities. In one implementation, the processor may include a circuit with instruction reading and running capabilities. For example, it includes an electronic control unit (ECU), a microcontroller unit (MCU) or a digital signal processor (DSP), etc. In another implementation, the processor can implement certain functions through the logical relationship of a hardware circuit, and the logical relationship of the hardware circuit is fixed or reconfigurable, such as a hardware circuit implemented by a processor as an application-specific integrated circuit (ASIC) or a programmable logic device (PLD), such as a field programmable gate array (FPGA). In a reconfigurable hardware circuit, the processor loads a configuration document to implement the process of hardware circuit configuration, which can be understood as the process of the processor loading instructions to implement the functions of some or all of the above units. Alternatively, the processor 1301 may be a combination of at least two of these processor forms, etc.

[0201] The processor 1301 can be used to read the program stored in the memory 1302 and execute the above Figure 2 And the operations performed by the motor controller in possible embodiments thereof.

[0202] Fig.13 The specific operation and beneficial effects of each unit in the motor controller 1300 can be found in the above Figures 2 to 9 The corresponding descriptions in possible embodiments thereof will not be repeated here.

[0203] An embodiment of the present application also provides a vehicle, which includes a steering system including the above-mentioned motor controller.

[0204] The present application also provides a chip, which is applied to the steering system of a vehicle. The chip includes a processor, a communication interface and a memory, wherein the communication interface is used to realize the reception and transmission of data, the memory is used to store computer programs or computer instructions, and the processor is used to execute the computer programs or computer instructions stored in the memory, so that the chip performs the above Figures 2 to 9 and any method described in any one of its possible implementations.

[0205] The embodiment of the present application also provides a computer-readable storage medium, which stores a computer program or computer instructions, and the computer program or computer instructions are executed by a processor to implement the above Figures 2 to 9 and any method described in any one of its possible implementations.

[0206] The present application also provides a computer program product. When the computer program product is executed by a processor, as described above Figures 2 to 9 Any of the methods described in the foregoing and possible implementations thereof will be implemented.

[0207] In summary, the solution of the embodiments of the present application can effectively reduce the resonance caused by the steering system, improve the user's driving experience and reduce potential safety hazards.

[0208] In this application, the terms "first", "second", etc. are used to distinguish between identical or similar items with substantially the same effects and functions. It should be understood that there is no logical or temporal dependency between "first", "second", and "nth", nor is there a limitation on the quantity and execution order. It should also be understood that although the following description uses the terms first, second, etc. to describe various elements, these elements should not be limited by the terms. These terms are only used to distinguish one element from another element.

[0209] It should also be understood that in the various embodiments of the present application, the size of the serial number of each process does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0210] It should also be understood that the term “comprise” (also known as “includes,” “including,” “comprises” and / or “comprising”) when used in this specification specifies the presence of stated features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0211] It should also be understood that the references to "one embodiment", "an embodiment", or "a possible implementation" throughout the specification mean that specific features, structures, or characteristics related to the embodiment or implementation are included in at least one embodiment of the present application. Therefore, the references to "in one embodiment" or "in an embodiment", or "a possible implementation" throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0212] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A vehicle steering control method, characterized in that: The method comprises: Acquiring a rotation speed signal of a motor in a steering system of the vehicle and a vehicle speed signal of the vehicle; generating a target vibration suppression torque signal based on the rotation speed signal and the vehicle speed signal; the target vibration suppression torque signal is used to adjust the power assist torque of the steering system; synthesizing a second torque signal based on the target vibration suppression torque signal and a first torque signal, wherein the first torque signal is determined based on a torque signal from a target sensor; the target sensor is used to detect a steering wheel torque signal of the vehicle; The motor is controlled based on the second torque signal to achieve power steering.

2. The method according to claim 1, characterized in that The generating a target vibration suppression torque signal based on the rotation speed signal and the vehicle speed signal comprises: acquiring a first vibration suppression torque signal based on the rotation speed signal, wherein a frequency of the first vibration suppression torque signal includes a resonance frequency of the vehicle; acquiring a target gain coefficient based on the vehicle speed signal; the target gain coefficient is used to adjust the amplitude of the first vibration suppression torque signal; The target vibration suppression torque signal is calculated based on the first vibration suppression torque signal and the target gain coefficient.

3. The method according to claim 2, characterized in that The obtaining of a first vibration suppression torque signal based on the rotation speed signal comprises: Extracting a second vibration suppression torque signal from the speed signal; the second vibration suppression torque signal includes a signal in the speed signal having a frequency of the resonance frequency; The phase of the second vibration suppression torque signal is adjusted to obtain the first vibration suppression torque signal; the phases of the first vibration suppression torque signal and the second vibration suppression torque signal are the same or different.

4. The method according to claim 3, characterized in that The adjusting the phase of the second vibration suppression torque signal comprises: The phase of the second vibration suppression torque signal is advanced and compensated.

5. The method according to claim 3 or 4, characterized in that: The step of extracting the second vibration suppression torque signal from the rotation speed signal comprises: The second vibration suppression torque signal is extracted from the rotation speed signal by a resonant oscillator; the amplitude gain of the resonant oscillator at the resonant frequency is 0 dB.

6. The method according to claim 3 or 4, characterized in that: The step of extracting the second vibration suppression torque signal from the rotation speed signal comprises: extracting a third vibration suppression torque signal from the speed signal through a high-pass filter; the cut-off frequency of the high-pass filter is less than the resonance frequency; extracting a fourth vibration suppression torque signal from the third vibration suppression torque signal through a low-pass filter; the cut-off frequency of the low-pass filter is greater than the resonance frequency; and the frequency of the fourth vibration suppression torque signal includes the resonance frequency; The amplitude of the fourth vibration suppression torque signal is adjusted by an amplitude adjustment module to obtain the second vibration suppression torque signal; the amplitude gain of the second vibration suppression torque signal at the resonance frequency is 0 dB.

7. The method according to any one of claims 2 to 6, characterized in that: The step of obtaining a target gain coefficient based on the vehicle speed signal includes: The target gain coefficient is searched in a negative gain relationship table based on the vehicle speed signal; the gain coefficient in the negative gain relationship table is less than zero.

8. The method according to claim 7, characterized in that The gain coefficient in the negative gain relationship table increases as the vehicle speed increases.

9. The method according to any one of claims 2 to 6, characterized in that: The step of obtaining a target gain coefficient based on the vehicle speed signal further includes: Searching for a negative gain coefficient in a negative gain relationship table based on the vehicle speed signal; the gain coefficient in the negative gain relationship table is less than zero; Searching for a positive gain coefficient in a positive gain relationship table based on the vehicle speed signal; the gain coefficient in the positive gain relationship table being greater than zero; The target gain coefficient is calculated based on the negative gain coefficient and the positive gain coefficient.

10. The method according to claim 9, characterized in that The gain coefficient in the negative gain relationship table increases as the vehicle speed increases, and the gain coefficient in the positive gain relationship table decreases as the vehicle speed increases.

11. The method according to any one of claims 1 to 10, characterized in that: The target sensor is also used to detect a steering wheel angle signal of the vehicle; The first torque signal is determined based on a torque signal from a target sensor, comprising: The first torque signal includes a signal obtained by one or more of the following processes based on the torque signal from the target sensor, the vehicle speed signal and the steering wheel angle signal: basic power assist control processing, high frequency gain processing, phase compensation and damping control processing.

12. A motor controller, characterized in that: The motor controller is applied to a steering system of a vehicle, and the motor controller comprises: An acquisition unit, used for acquiring a rotation speed signal of a motor in a steering system of the vehicle and a vehicle speed signal of the vehicle; a resonance suppression processing unit, configured to generate a target vibration suppression torque signal based on the rotation speed signal and the vehicle speed signal; the target vibration suppression torque signal is used to adjust the power assist torque of the steering system; a synthesis unit, configured to synthesize a second torque signal based on the target vibration suppression torque signal and a first torque signal, wherein the first torque signal is determined based on a torque signal from a target sensor; the target sensor is configured to detect a steering wheel torque signal of the vehicle; A control unit is used to control the motor to achieve power steering based on the second torque signal.

13. The motor controller according to claim 12, characterized in that: The resonance suppression processing unit is specifically used for: acquiring a first vibration suppression torque signal based on the rotation speed signal, wherein a frequency of the first vibration suppression torque signal includes a resonance frequency of the vehicle; acquiring a target gain coefficient based on the vehicle speed signal; the target gain coefficient is used to adjust the amplitude of the first vibration suppression torque signal; The target vibration-suppression torque signal is generated based on the first vibration-suppression torque signal and the target gain coefficient.

14. The motor controller according to claim 13, characterized in that: The resonance suppression processing unit is specifically used for: Extracting a second vibration suppression torque signal from the speed signal; the second vibration suppression torque signal includes a signal in the speed signal having a frequency of the resonance frequency; The phase of the second vibration suppression torque signal is adjusted to obtain the first vibration suppression torque signal; the phases of the first vibration suppression torque signal and the second vibration suppression torque signal are the same or different.

15. The motor controller according to claim 14, characterized in that: The resonance suppression processing unit is specifically used for: The phase of the second vibration suppression torque signal is advanced and compensated.

16. The motor controller according to claim 14 or 15, characterized in that: The resonance suppression processing unit is specifically used for: The second vibration suppression torque signal is extracted from the rotation speed signal by a resonant oscillator; the amplitude gain of the resonant oscillator at the resonant frequency is 0 dB.

17. The motor controller according to claim 14 or 15, characterized in that: The resonance suppression processing unit is specifically used for: extracting a third vibration suppression torque signal from the speed signal through a high-pass filter; the cut-off frequency of the high-pass filter is less than the resonance frequency; extracting a fourth vibration suppression torque signal from the third vibration suppression torque signal through a low-pass filter; the cut-off frequency of the low-pass filter is greater than the resonance frequency; and the frequency of the fourth vibration suppression torque signal includes the resonance frequency; The amplitude of the fourth vibration suppression torque signal is adjusted by an amplitude adjustment module to obtain the second vibration suppression torque signal; the amplitude gain of the second vibration suppression torque signal at the resonance frequency is 0 dB.

18. The motor controller according to any one of claims 13 to 17, characterized in that: The resonance suppression processing unit is specifically used for: The target gain coefficient is searched in a negative gain relationship table based on the vehicle speed signal; the gain coefficient in the negative gain relationship table is less than zero.

19. The motor controller according to claim 18, characterized in that: The gain coefficient in the negative gain relationship table increases as the vehicle speed increases.

20. The motor controller according to any one of claims 13 to 17, characterized in that: The resonance suppression processing unit is specifically used for: Searching for a negative gain coefficient in a negative gain relationship table based on the vehicle speed signal; the gain coefficient in the negative gain relationship table is less than zero; Searching for a positive gain coefficient in a positive gain relationship table based on the vehicle speed signal; The gain coefficient in the positive gain relationship table is greater than zero; The target gain coefficient is calculated based on the negative gain coefficient and the positive gain coefficient.

21. The motor controller according to claim 20, characterized in that: The gain coefficient in the negative gain relationship table increases as the vehicle speed increases, and the gain coefficient in the positive gain relationship table decreases as the vehicle speed increases.

22. The motor controller according to any one of claims 12 to 21, characterized in that: The target sensor is also used to detect a steering wheel angle signal of the vehicle; The first torque signal is determined based on a torque signal from a target sensor, comprising: The first torque signal includes a signal obtained by one or more of the following processes based on the torque signal from the target sensor, the vehicle speed signal and the steering wheel angle signal: basic power assist control processing, high frequency gain processing, phase compensation and damping control processing.

23. A motor controller, characterized in that: The motor controller is applied to the steering system of a vehicle, and the motor controller includes a processor, a communication interface and a memory, wherein the communication interface is used to realize the reception and transmission of data, the memory is used to store computer programs or computer instructions, and the processor is used to execute the computer programs or computer instructions stored in the memory, so that the motor controller executes the method described in any one of claims 1-11.

24. A steering system, characterized in that: The steering system comprises a motor controller as claimed in any one of claims 12 to 22; or, The steering system includes the motor controller of claim 23.

25. A vehicle, characterized in that: Comprising a steering system as claimed in claim 24.

26. A chip, characterized in that: The chip is applied to a steering system of a vehicle, and the chip includes a processor, a communication interface and a memory, wherein the communication interface is used to realize the reception and transmission of data, the memory is used to store computer programs or computer instructions, and the processor is used to execute the computer programs or computer instructions stored in the memory, so that the chip executes the method described in any one of claims 1-11.

27. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program or computer instructions, and the computer program or computer instructions are executed by a processor to implement the method according to any one of claims 1 to 11.

28. A computer program product, characterized in that When the computer program product is executed by a processor, the method described in any one of claims 1 to 11 will be implemented.

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