Optimum traction force distribution for stability improvement of 4WD EV in critical driving condition

This paper is concerned with integrated yaw stability control strategy for 4WD EV driven by in-wheel motors. The strategy consists of double control loops. One is the upper control loop, which uses 2-DOF control method to specify control effectors which are required for keeping EV yaw stability. The other is the lower control loop, which is used to determine control inputs for four driving motors by optimum traction force distribution method. This distribution method is implemented by redundancy control. The simulation results indicate that handling stability of this 4WD EV is improved by proposed strategy, especially when the EV drives in critical conditions