Fixed-time fault-tolerant control of electric multiple unit based on fuzzy adaptive

A fault-tolerant controller is designed using a fuzzy control strategy for scenarios in which there are external disturbances and partial failures of traction/braking actuators during the operation of Electric Multiple Unit (EMU). Firstly, the kinematic equations are listed in the force analysis. The single-mass model of the EMU under the fault is established by considering the external perturbation and the partial failures of the actuators. Secondly, within the framework of the backstepping method, a fuzzy logic system is used to approximate the uncertainty terms in the single-mass mode and an adaptive strategy is used to estimate in real time the uncertainty values present in the system function. Finally, the fault-tolerant controller design process is closely integrated with the finite-time Lyapunov stable theory, which ensures that the closed-loop system consisting of the single-mass model and the controller is stable. The tracking error can converge to a small neighbourhood near the origin at a fixed time, and the convergence time is independent of the initial state of the system. The simulation results show that the CRH3 EMU can effectively track the desired position and speed curves, and the precision stopping error meets the requirement within ±30cm.