Study On Traction Control Of Front And Rear Wheel Independent Drive Type Electric Vehicle

With the increasing serious problems of environmental pollution and energy crisis,pure electric vehicles which is energy saving and environmentally friendly has become the focus of research in recent years,and it has broad prospects for development,and has been attached importance by major automobile manufacturers and governments.Due to the constraints of the battery cost and the driving range,and the low load rate of the traditional single-motor-driven pure electric vehicle,it is difficult to popularize the pure electric vehicle,therefore,research and development of a new type of electric drive system with high efficiency and low cost is one of the key technologies to promote the industrialization of electric vehicles.To solve the above problems,this paper focus on a kind of power transmission system of electric vehicle with front and rear axles wheel independent drive,The several aspects of research content as following:?study on the relationship of dynamic characteristics and dynamic parameters of the vehicle,According to the performance requirements of the vehicle,matching the suitable parameters includes two motors and final drive,On the basis of this,analyze the frequency statistics of vehicle speed,power demand and demand torque by doing statistics of vehicle operating point at rated frequency,when matching parameters of the vehicle,try to make the vehicle working frequency range at high efficiency of the motor,the parameters of each component of the system are preliminarily determined.?The optimized mode and power split plan in any vehicle speed,acceleration and SOC scopes are calculated,respectively,the control strategy is made up,and the boundary of each mode is obtained by projecting the efficiency surfaces of each mode.Detail transmission simulation model is developed by using Simulink,with which the range simulations with a 60-km/h constant speed and NEDC,10-15,and UDDS driving cycles are implemented,verified the correctness of the power transmission system parameters matching and the rationality of the control strategy.?According to the relationship between road adhesion coefficient and drive wheel slip ratio,determined the optimum slip ratio of drive wheel;formulated traction control strategy and the trigger/exit decision logic of traction control system;designed a traction controller to realize above control strategies.?Established an offline simulation model for this vehicle by using Simulink software,simulated and verified those control strategies in complex road conditions.The simulation results show that under complex conditions,traction control strategy can effectively suppress the excessive slip of driving wheels,and make the full use of the current road conditions,ensure the vehicle's speedup performance...