Dual-motor Independent Drive Electric Vehicle Stability Control And Test Vehicle Design,

The stability augmentation systems are classified as the indirect stability system and the direct stability system according to their control targets in this thesis. The former one aims to optimize the motion of wheels and the latter one is to directly control the motion of vehicle.This paper proposes an anti-skid traction control system by using velocity information of the free wheel for a two-motor driven EV. Theoretical investigation on the dynamics of cornering process is carried out, and based on Ackermann- Jeantand model the conditions that the driving-torques should fulfill for optimal cornering are obtained. In the light of the analyses above, a double-mode electronic differential strategy is suggested.The producing of direct yaw-moment is reviewed and a feedforward direct yaw-moment controller (DYC) is designed to limit the sideslip of vehicle. Computer simulations show that the control is able to improve vehicle handling and stability to a certain extent, but that is severely influenced by nonlinearity of the plant. Using implicit model following method, a state feedback DYC is designed to stabilize the vehicle motion. Simulation results verify that the controller can provide extremely low sideslip and stable yaw rate response with little hysteresis, further, it shows robustness on various road conditions. The influence of FWD or RWD configuration on DYC's performance is discussed. The control's robustness against varying of vehicle parameters also is verified.An experimental vehicle with 2 permanent magnet synchronous motors is designed and built for future testing of the control methods mentioned above. In primary test-driving it shows good performance whether in cornering or straight accelerating.