Control strategies for four in-wheel driven electric vehicles when motor drive systems fail

This paper focuses on the design of control strategy in four-wheel independent drive (4WID) electric vehicles when motor drive systems fail. We proposed a control strategy to maintain the performance and stability for the 4WID electric vehicles with motor drive systems failure. Firstly, failure modes of motor drive systems are classified and analyzed as Failure-Driving mode and Failure-Stopping mode. Secondly, a twolayer-control-model (upper layer and lower layer) is presented to maintain the performance and stability of the vehicle by controlling the normal motor drive systems for Failure-Driving mode; In the upper layer, fuzzy logic direct yaw-moment control (DYC) is proposed. In the lower layer, a control algorithm is designed to distribute torque to motor drive systems without failure. The effectiveness of the control strategies have been examined using a driving simulator system.