A Fault-Tolerant Control Strategy for Distributed Drive Electric Vehicles Based on Model Reference Adaptive Control

Abstract

This study addresses the issue of compromised performance and stability in distributed drive electric vehicles during high-speed operation in the event of motor failure. A fault-tolerant control strategy for distributed drive electric vehicles is proposed, based on model reference adaptive control (MRAC). First, a seven-degree-of-freedom vehicle dynamics reference model is established, from which the output torque of each wheel during stable operation is determined. Secondly, based on the compensation principle that maintains constant longitudinal speed and total torque before and after the fault, the output torque of the remaining wheels is determined to ensure normal vehicle operation in the event of a single motor failure. To improve torque distribution accuracy, an MRAC controller that takes into account the output hysteresis of the motor is designed. The transfer functions of both the reference model and the actual model are derived. Using Lyapunov’s second method, the adaptation rate of the MRAC system is formulated, ensuring that the state of the actual model converges to that of the reference model, thereby achieving adaptive regulation of system parameters and global stability. Finally, simulation experiments are conducted under high-speed dual-lane conditions. The results indicate that, in the case of a single motor failure with constant vehicle speed, the yaw rate and lateral displacement of the vehicle’s center of mass decrease, thereby validating the effectiveness of the proposed fault-tolerant control strategy.