Research On Multi-motor Control Based On Steer By Wire Of 4wid/s Electric Vehicle

Four-wheel independent drive/steering(4WID/S)electric vehicle is free of the shackles of mechanical connections,which chassis adopt fully-wire control technology,and the independent control of each actuators improves the vehicle's handling mobility and stability.Meanwhile the control is also more complicated,which has attracted extensive attention and research.In this paper,the multi-motor control of 4WID/S electric vehicle steer-by-wire are studied.The main research contents are as follows:Firstly,the research status of steer-by-wire technology in domestic and overseas is investigated,particularly in the aspects of steer-by-wire motor control.The research significance and content of the subject are put forward.The 4WID/S electric vehicle dynamics model is established by CarSim,and the steer-by-wire mathematical model and steering motor control model are constructed by combining Matlab,which lays a foundation for the research of the subject.Secondly,aiming to provide the driving sense of absence,the permanent magnet synchronous motor(PMSM)is used as the road-sensing motor.The current loop controller of PMSM is designed based on the first-order linear active disturbance rejection control,and the parameters of the controller are self-tuning and iterative optimization by the differential evolution algorithm to avoid the low efficiency and inconvenience of manual adjustment and improve the control performance of the current loop of the road sense motor.The driver can be supplied the smoother hand feel and real-time road-sensing;Thirdly,pointing at improving the mobility and stability in vehicles steering,the four-wheel active steering controller based on the second-order linear active disturbance rejection control is designed.The unmodeled and unknown disturbances are observed and compensated,and each wheel angles are corrected in real time to improve the vehicle handling stability and anti-disturbance ability.The two-phase hybrid stepping motor is used as the steering executive motor,and the control method of steering executive multi-motor is researched,and the parabola acceleration and deceleration operation curve is designed to improve the torque of the executive motor when steering.Finally,the 4WID/S electric vehicle experiment platform is built,and the DSP TMS320F28335 is used as the central processing unit.The hierarchical control structure based on CAN bus is adopted to design the hardware,software and host computer in the platform,and the proposed active steering control and steering execution multi-motor control algorithm are verified.The verification for the proposed road-sensing motor control algorithm is carried out in combination with Labview RT\CarSim.The correctness and effectiveness of the control algorithm are proved via two parts of verification results.