Adaptive Fault-Tolerant Control Strategy for Drive Actuators in Four-Wheel Independent Drive Electric Vehicles

An adaptive nonsingular fast integral terminal sliding mode fault-tolerant control (ANFITSMFTC) strategy is proposed to guarantee the handling and stability of the four-wheel independent drive electric vehicles (4WID-EVs) in the presence of unknown faults in in-wheel motors. Aiming at the loss-of-effectiveness faults of the in-wheel motors, the ANFITSMFTC method is proposed to constrain the additional lateral force and the yaw moment, so as to track the ideal side slip angle and the yaw rate during 4WID-EV driving to ensure its stability. Subsequently, the derived constraint conditions are optimized to calculate the braking torque increments of each wheel, which are applied to 4WID-EV to achieve fault tolerance. The stability of the control scheme is proved by the application of Lyapunov stability theory and Barbalat’s lemma. Finally, commercial softwares CarSim and MATLAB/Simulink are used for joint simulation to verify the effectiveness of the proposed control algorithm, which lays a foundation for improving the safety of the electric vehicles.