Stability Control System for Four-in-Wheel-Motor Drive Electric Vehicle

A direct yaw-moment control (DYC) method is proposed for the purpose of improving the handling stability of an all in-wheel motor drive electric vehicle (EV). The control system in combination with a fuzzy logic direct yaw-moment controller and an active front steering controller based on sliding mode control. By measurements of vehicle states, the control algorithm determines the level of vehicle stability and intervenes as necessary through individual wheel traction control to provide added stability and handing predictability. Therefore, the stability control system distributes torque and power to each motor to meet the requirements of each wheel. The effectiveness and validation of the proposed control method are evaluated both by Matlab/Simulink based on simulations and experiments. Simulation and experiment results of dynamic responses for sideslip angle and yaw rate of the EV manifest that the DYC system can assist drivers with controlling the stability of the vehicle during adverse driving maneuvers over a variety of road conditions and enhance the handling stability of the EV.