Research Of In-wheel Motor Design And Driving Control Strategy For Electric Vehicle

The number of domestic and foreign vehicles are growing,which make the increasingly serious energy and environmental problems.In order to reduce the use of fossil energy,electric vehicles are gradually becoming the focus of research,of which four wheel drive wheel electric vehicle with unique structure and control advantages,and have got attention of the universities and research organizations.In order to study the four wheel electric vehicle’s drive force distribution and the stability,it is necessary to determine the parameters of the vehicle body,which is the basis of the following simulation research work.In this paper a model was chosen.The weight of vehicle and tire model parameters were determined by analysis.According to the dynamic performance of the vehicle,the parameters of the drive system were designed.Also the structure of in-wheel motor was designed,to lay the foundation for the construction of follow-up test prototype.According to the designed parameters,the dynamic model of the vehicle was established,including the dynamic model of the vehicle body,the driving wheel rotation model,and the corresponding simulink simulation model was built.On the basis of analysis of the vehicle dynamics model,with the purpose of maintaining the stability of lateral velocity and yaw rate,lateral velocity controller and yaw rate controller were designed,the two controllers adopted the fuzzy PID algorithm,the controllers’ output values were the additional lateral force and additional yaw moment,but these two values cannot be directly used on the four wheel.In this paper,a linear constraint distribution method was proposed,which took the output value of the two controllers and the driving force of maintaining the speed as the constraint conditions to calculate the driving force of the four wheels.At last,the independent Simulink model,and Simulink/Carsim co-simulation model were built,which were used to validate the proposed method.The Simulink and Simulink/Carsim simulation shows that,the fuzzy PID controllers used in this paper and linear constraint distribution method of driving force can make lateral velocity and yaw rate tracking the change of the expected value,maintaining the vehicle’s driving stability effectively.