Electronic stability control for direct-drive Electric Vehicle

This paper presents system analysis, modeling and simulation of an Electric Vehicle (EV) with two independent rear wheel drives. An electronic stability control strategy is proposed to guarantee the EV dynamics and stability in this case of no traditional mechanical differential. The dynamic model of the vehicle system is initially developed and simulated using MATLAB with the proposed control algorithm. The control system combine the merit of different types of control schemes: Slip ratio control (SRC) system and direct yaw moment control. This control structure ensures that the vehicle can maintain two driven motor at a synchronous speed by estimating tire traction force when moving straightly. When the vehicle is cornering, the proposed control is applied to distribute the torque of the dual motors appropriately so that the cornering behavior of vehicle becomes more stable and comfortable. The strategy that the wheels speed and yaw rate of vehicle was not use as feedback control variables, thus this reduce the risk for the driver losing control of the vehicle, especially during bad road condition. The preliminary result shows that the proposed control approach operates satisfactorily and is suitable for implementation.