CN-121990049-A - Dual-motor road feel feedback system suitable for steer-by-wire vehicle and control method thereof

CN121990049ACN 121990049 ACN121990049 ACN 121990049ACN-121990049-A

Abstract

The invention provides a double-motor road feel feedback system suitable for a steer-by-wire vehicle and a control method thereof, and belongs to the field of steer-by-wire. The system aims to solve the problems that an existing worm and gear type road feel feedback system is complex in structure and low in stability and control precision, the road feel feedback system is invalid due to single motor faults to influence the safety of a driver in operating a vehicle, and decoupling design advantages and safety redundancy of a steering wheel and a steering gear of a steer-by-wire system are not fully exerted. According to the invention, through the parameter identification of the road feel feedback system, each dynamic characteristic parameter and system design parameter of the road feel feedback system are obtained, the permanent magnet synchronous motor is adopted as a road feel feedback execution motor aiming at the interference of an ideal feedback moment output signal, a robust controller based on active disturbance rejection control is designed, the anti-disturbance performance of the system is improved, the ideal feedback moment signal can be tracked in real time, the tracking error precision is high, and the driving safety and the control experience of a driver are greatly improved through the design of the double motors.

Inventors

WANG JIANFENG
YU YANG
LIU HAOJIE
CHEN RUOXIN
LU ZIYU
LI XINGCHEN
Guo Mengteng

Assignees

哈尔滨工业大学（威海）

Dates

Publication Date: 20260508
Application Date: 20260324

Claims (7)

1. A dual-motor road feel feedback system suitable for a steer-by-wire vehicle is characterized by comprising a dual-motor road feel feedback execution module, a road feel feedback system parameter identification module and a road feel motor moment tracking control module, The double-motor road sense feedback module comprises a steering wheel (1), a steering wheel transmission gear mechanism (2), a steering wheel corner sensor transmission gear mechanism (3), a steering wheel corner sensor (4), a dynamic torque sensor (6), a dynamic torque sensor transmission gear mechanism (7), an M1 road sense motor transmission gear mechanism (9), an M2 road sense motor transmission gear mechanism (10), an M1 road sense motor (12) and an M2 road sense motor (13); The steering wheel (1) is connected with a steering wheel transmission gear mechanism (2), the steering wheel transmission gear mechanism (2) is connected with a steering wheel corner sensor transmission gear mechanism (3), the steering wheel corner sensor (4) is connected with the steering wheel corner sensor transmission gear mechanism (3), the steering wheel corner sensor (4) is used for collecting a corner signal input by a driver into the steering wheel (1) and sending the collected signal to a whole vehicle controller, the steering wheel transmission gear mechanism (2) is sequentially connected with a dynamic torque sensor (6), a dynamic torque sensor transmission gear mechanism (7), an M1-way motor transmission gear mechanism (9) and an M1-way motor (12), the M2-way motor transmission gear mechanism (10) is connected with the M1-way motor transmission gear mechanism (9), and the M2-way motor transmission gear mechanism (10) is connected with the M2-way motor (13) and sends the moment signal output by the double-motor to the whole vehicle controller; The road feel feedback system parameter identification module receives steering wheel rotation angle and double-motor output torque signals from the whole vehicle controller based on sweep frequency experimental design, and calculates each dynamic characteristic parameter and system design parameter of the road feel feedback system through test and data processing by comparing the steering wheel rotation angle and double-motor output torque signals with angle and torque output values measured by built-in sensors in an M1 road feel motor (12) and an M2 road feel motor (13); The road sensing motor moment tracking control module receives ideal feedback moment calculated by an upper road sensing feedback algorithm in the whole vehicle controller, carries out tracking feedback on the feedback moment through active disturbance rejection control, and calculates the optimal control rate of the double motors, namely the output torque of the double motors.
2. The dual-motor road feel feedback system suitable for the steer-by-wire vehicle according to claim 1, wherein the dynamic torque sensor (6) is arranged on a dynamic torque sensor mounting and fixing bracket (5), the M1 road feel motor (12) and the M2 road feel motor (13) are both arranged on a road feel motor mounting and fixing bracket (11), and the dynamic torque sensor mounting and fixing bracket (5) is fixedly connected with the road feel motor mounting and fixing bracket (11).
3. A dual motor road feel feedback system suitable for steer-by-wire vehicles as claimed in claim 2, wherein the dynamic torque sensor transmission gear mechanism (7), the M1 road feel motor transmission gear mechanism (9) and the M2 road feel motor transmission gear mechanism (10) are externally provided with a gear box protection cover (8).
4. A control method of a two-motor road feel feedback system for a steer-by-wire vehicle according to any one of claims 1 to 3, characterized by comprising the steps of: s100, establishing a vehicle double-motor road feel feedback system and a dynamics model thereof; s200, completing parameter identification of the system based on the test of the vehicle double-motor road feel feedback system established in the step S100, and determining each dynamic characteristic parameter and system design parameter of the road feel feedback system; s300, designing a moment tracking controller based on active disturbance rejection control on the basis of selecting a permanent magnet synchronous motor according to the ideal feedback moment calculated by an upper layer road feel feedback algorithm, the dynamic model of the vehicle double-motor road feel feedback system established in the step S100 and the parameters obtained in the step S200.
5. A control method of a two-motor road feel feedback system adapted to a steer-by-wire vehicle according to claim 4, characterized in that in step S100, The driver inputs steering torque, overcomes friction, inertia and damping of the steering wheel (1) and the steering wheel transmission gear mechanism (2) and the dynamic torque sensor, and then makes the dynamic torque sensor twist: (1) In the formula, Steering torque input for the driver; The equivalent moment of inertia of the steering wheel (1), the steering wheel transmission gear mechanism (2) and the dynamic torque sensor; equivalent damping coefficients of the steering wheel (1), the steering wheel transmission gear mechanism (2) and the dynamic torque sensor are obtained; is the turning angle of the steering wheel (1); is equivalent friction torque between the steering wheel (1) and the steering wheel transmission gear mechanism (2) and between the dynamic torque sensor; A planetary gear reduction ratio is built in the road sensing motor; the motor is a road sensing motor corner; Torsional stiffness for the dynamic torque sensor (6); After the electromagnetic torque of the road sensing motor overcomes friction, inertia and damping of the road sensing motor and a transmission gear, the dynamic torque sensor (6) is driven to twist: (2) in the formula, Electromagnetic torque of the left and right side road induction motors is respectively; The equivalent friction torque between the road sensing motor and the transmission gear is obtained; Damping coefficients of the left and right side road induction motors respectively; is divided into moment of inertia of the left and right side road induction motors, and is also provided with , ; And (3) combining the formula (1) and the formula (2) to obtain an equivalent kinetic equation of the double-motor road feel feedback system, wherein the equivalent kinetic equation is as follows: (3) (4) in the formula, Inputting a steering angle for a steering wheel (1) the road sensing motor outputs a rotation angle difference value, Is equivalent friction torque between the road sensing motor and the steering wheel (1); equivalent moment of inertia between the road sensing motor and the steering wheel (1); equivalent damping coefficient between the road sensing motor and the steering wheel (1); is equivalent torsional rigidity between the road sensing motor and the steering wheel (1).
6. The method for controlling a dual motor road feel feedback system for a steer-by-wire vehicle of claim 5, wherein in step S200, The static loading measurement is designed aiming at equivalent torsional rigidity and equivalent friction torque, namely, a steering wheel (1) is fixed, an M1-path induction motor (12) and an M2-path induction motor (13) are used as standard power sources, the torque is slowly and gradually increased, a steering wheel angle sensor (4) and a dynamic torque sensor (6) respectively collect the actual angle of the steering wheel (1) and the torque actually obtained by the steering wheel (1), and the actual output angle and the actual output torque of the M1-path induction motor (12) and the M2-path induction motor (13) which are measured by the built-in sensors of the path induction motor are subjected to difference to obtain a torque difference and an angle difference; The response of the system under different frequencies is collected through sweep test, wherein an M1-path induction motor (12) and an M2-path induction motor (13) are set to be in a torque control mode, approximate sine moments are output according to gradually increasing frequencies, the steering wheel (1) is empty, the actual rotation angle of the steering wheel (1) and the moment actually obtained by the steering wheel (1) are collected through a steering wheel rotation angle sensor (4) and a dynamic torque sensor (6), moment data output by the M1-path induction motor (12) and the M2-path induction motor (13) are collected through a path induction motor built-in sensor, a sweep test target signal is gradually increased to 3Hz from 0.2Hz, the target moment amplitude is 0.5N.m, the obtained moment difference is the damping, inertia and friction moment consumed by each part in the rotation process of the path induction feedback system, the determined equivalent friction moment and the elastic deformation moment obtained by the equivalent torsional rigidity are compensated, and the system equivalent damping coefficient and inertia coefficient moment difference are obtained through adjustment and zero.
7. The method for controlling a dual motor road feel feedback system for a steer-by-wire vehicle of claim 6, wherein in step S300, The M1-path induction motor (12) and the M2-path induction motor (13) are permanent magnet synchronous motors and ideal motors, and a PMSM voltage equation is established under a synchronous rotation coordinate system of an excitation shaft and a torque shaft: (5) (6) The electromagnetic torque of the surface-mounted permanent magnet synchronous motor is as follows: (7) in the formula, Exciting shaft voltage and torque shaft voltage respectively; Is a stator resistor; Exciting shaft current and torque shaft current respectively; The excitation shaft inductance and the torque shaft inductance are respectively; is the number of magnetic pole pairs; the motor rotation speed; Is a rotor permanent magnet flux linkage; Introducing active disturbance rejection control, taking coupling items of a torque shaft and an excitation shaft as system disturbance respectively, and estimating total disturbance including the coupling items from input and output of a motor control system by using an extended state observer; set total interference of excitation shaft And total torque axis disturbance The method comprises the following steps: (8) (9) The control input of the exciting shaft current loop is set as exciting shaft voltage The torque shaft current loop control input is the torque shaft voltage The state space equations for the excitation and torque axes are: (10) (11) in the formula, Are all the state parameters of the current loop, ; Designing an extended state observer to estimate total excitation axis interference And total torque axis disturbance For a torque shaft, its extended state observer is: (12) (13) in the formula, Respectively is output to And total interference to the torque axis Is a function of the estimated value of (2); respectively differentiating the estimated values; Gain coefficients of the state observer respectively; the concept of bandwidth is adopted, and the bandwidth of a current loop is taken as And (2) and The characteristic polynomial of the current loop expansion state observer is Where s represents the complex variable of the Laplace transform, making the extended state observer take the form of an ideal characteristic equation Observer gain factor ; And compensating the estimated interference by adopting a linear state error feedback control strategy to obtain excitation shaft current and torque shaft current control law, wherein the obtained excitation shaft current and torque shaft current control law is as follows: (15) (16) in the formula, Obtaining excitation shaft and torque shaft voltages for linear error feedback respectively; Target currents of the excitation shaft and the torque shaft are respectively; the method comprises the steps of outputting an estimated value of current and an estimated value of total interference for an exciting shaft current loop expansion state observer; The current loops for the excitation and torque axes control the gain, respectively.

Description

Dual-motor road feel feedback system suitable for steer-by-wire vehicle and control method thereof Technical Field The invention relates to the technical field of steer-by-wire, in particular to a dual-motor road feel feedback system suitable for a steer-by-wire vehicle and a control method thereof. Background With the rapid development of automobile intelligent chassis technology, the wire control technology is increasingly widely applied to the field of automobile chassis. The linear steering technology is the basis for realizing a sliding plate type chassis and a wheel angle module. The steer-by-wire system replaces the traditional mechanical connection by the electronic signal, and the direct mechanical linkage between the steering wheel and the steering wheel is canceled, so that more flexible steering control, higher energy efficiency and better driving experience can be realized. However, steer-by-wire systems also face a number of technical challenges, where road feel feedback is an important way for the driver to perceive the driving state of the vehicle, directly affecting the driving safety and steering experience, and how to provide a driver with a real, reliable road feel feedback in the absence of a mechanical connection is one of the key issues. For the road feel feedback system, the existing research is mostly focused on the calculation of ideal feedback moment matched with the road surface condition, and the design and control of the mechanism of the road feel feedback system, especially the design method of the double-motor road feel feedback system, are less disclosed. Meanwhile, most of the road feel feedback execution motors in the existing researches adopt simple permanent magnet brushless direct current motors, and although the road feel feedback system has low cost and simple control, the road feel feedback system needs the motor to output a continuous, smooth and fast-response moment signal to simulate various resistances felt by a steering wheel, and the inherent magnetic circuit and counter electromotive force waveform characteristics of the permanent magnet brushless direct current motors also cause the inherent shortages of torque control smoothness and linearity, so that the road feel 'rough' and 'step feel' can be caused, and continuous smooth force feel transmitted by a real steering wheel or a road surface can not be simulated. The existing road sense feedback mechanism is designed to imitate the traditional C-EPS system, and a motor, a worm gear reducer or a ball screw and a torsion bar are adopted to drive the steering wheel. The worm gear or the ball screw also can cause the friction force of the whole system to be increased, has nonlinear characteristics, influences the control precision of the system, does not fully exert the advantages of decoupling a steering wheel and a steering gear of the steer-by-wire system and being capable of being independently designed. Disclosure of Invention The invention aims to solve the technical problems that: The system aims to solve the problems that the existing worm and gear type road feel feedback system is high in number of design parts, complex in system structure and low in system stability and control precision, meanwhile, the road feel feedback system is directly caused to fail due to single motor faults, the safety of a driver operating a vehicle is affected, and the decoupling design advantages and safety redundancy of a steering wheel and a steering gear of the drive-by-wire steering system are not fully exerted. The invention adopts the technical scheme for solving the technical problems: The invention provides a double-motor road feel feedback system suitable for a steer-by-wire vehicle, which comprises a double-motor road feel feedback execution module, a road feel feedback system parameter identification module and a road feel motor moment tracking control module, The double-motor road sense feedback module comprises a steering wheel, a steering wheel transmission gear mechanism, a steering wheel corner sensor, a dynamic torque sensor transmission gear mechanism, an M1 road sense motor transmission gear mechanism, an M2 road sense motor transmission gear mechanism, an M1 road sense motor and an M2 road sense motor; The steering wheel is connected with a steering wheel transmission gear mechanism, the steering wheel transmission gear mechanism is connected with a steering wheel corner sensor transmission gear mechanism, the steering wheel corner sensor is connected with the steering wheel corner sensor transmission gear mechanism, the steering wheel corner sensor is used for collecting a steering wheel corner signal input by a driver and transmitting the collected signal to the whole vehicle controller, the steering wheel transmission gear mechanism is sequentially connected with a dynamic torque sensor, a dynamic torque sensor transmission gear mechanism, an M1-way induction motor transmission gear mechanism and an M1-w