Research On High-Performance Motion Conrtol Of Electric Vehicle

With the increasing amount of vehicles, the problem of automobile accident is getting worse. Safety control problem of electric vehicle or other vehicle based on the model of four-wheel vehicles is becoming a new focus of the application research of control theory. In this paper, the problem of steer motion stabilization is researched, and a high-performance motion control scheme of electric vehicles proposed.This paper is divided into two parts. In the first part, the vehicle model of three degrees of freedom and the relationship between the slip ratio of a tire and the friction coefficient of the road surface is analyzed. A state observer to estimate the lateral angle of vehicle is designed. An anti-skid control method based on a back EMF observer and model following controller is designed. Then, a steer motion control scheme for electric vehicle with distribution of driving or braking force is designed based on disturbance observer and feed-forward compensator. Simulation results show that this control method improve the vehicle stability largely.The second part introduced the sensorless control method of BLDC motor used in electric vehicles drive system. By detecting the zero-cross point of Back-EMF, and a position estimation method, the starting of zero speed and non-zero speed is realized in experiments. A small power controller prototype is completed, and the test results show its reliability in most situations.