All Electric Wheel Vehicle Stability Control Strategy Research

With the deepening of the energy crisis and more serious environmental pollution, the electric vehicles are being paid more and more attention to. An electric vehicle with all motorized wheels has simple structure, high transmission efficiency, independent driving wheel and big potential to improve vehicle stability. In order to improve vehicle driving stability, torque distribution strategy of motorized wheels is studied in this thesis.Firstly, dynamics model with14degrees of freedom (DOF) for all-motorized-wheels vehicle is established in this thesis, which contains6-DOF of body movements,4-DOF of suspension movements and4-DOF of wheel rotations. The vehicle dynamics simulation model is established by using MATLAB/Simulink software, whose accuracy is verified by CarSim software.Secondly, vehicle sideslip angle is estimated raced on extended Kalman filter. Considering the complexity of the tire model, the longitudinal force and the lateral force of tire are estimated.Then, the two kinds of torque distribution strategy of electric vehicle when steering are mainly put forward in this thesis, which are based on loads of tire and yaw moment.Finally, the simulation of the control system is conducted. The simulation results show that the torque distribuiion strategy of motorized wheels designed in this thesis solved the torque coordination problems at steering and improved the driving stability of vehicle.The motorized wheels distribution strategy is designed to improve vehicle driving stability, and the control effect is ideal. It can provide reference to the research on the technology of motorized wheels.