Research And Development On Active Wheel Electric Vehicle

Environmental protection and energy saving are the great theme of the 21 century world,by that,China has given a policy of building economical society including a sub policy of develop small vehicles.An approach to make that true is to develop electric vehicles.Though there is a history of R&D on EV the industrialization has never come by the limit of battery,motor and control strategy.The actuality and trends of active wheel electric vehicles home and abroad are reviewed.Analyze the keystone and the challenge in the current development period of active wheel electric vehicles and point out the key technology and technical direction to be researched.This paper focused on the analysis of four-wheel-drive system motor control and four wheels' velocity coordination,introduced Delft's semi-empirical magic tire model,and attached slip rate feedback control based on the speed control.Control strategy is given in detail.For brushless DC motor for electric wheel motors for EV, make a car traveling on a straight line,angle-step,single-shift line and double-shift line move with two degrees freedom model and simulate.Applying MATLAB/SIMULINK software simulate and analyze the system,we can see that the body mass centre side slip angle,wheel side slip angle and the rate of wheel slide from the new coordinate control algorithm are better than that from the traditional mechanical differential.Therefore to ensure better control of vehicle performance and response characteristics is possible.In addition,each wheel attachment coefficient is high,so vehicle can get an ability of greater acceleration or deceleration.