Integrated Finite-Time Fault-Tolerance Terminal Sliding Mode Control of Brushless DC Motors (BLDC) Based on Finite-Time Fault Detection and Estimation

Abstract

This study introduces an innovative control framework for enhancing the reliability and performance of Brushless DC Motors through advanced fault-tolerant techniques. The developed method- ology combines terminal sliding mode control with a dual-estimation scheme to achieve simultaneous finite-time convergence of system states, disturbances, and fault signals. Departing from conventional approaches, the proposed solution uniquely decouples and independently estimates fault conditions and external disturbances within guaranteed time bounds while ensuring rapid convergence of motor outputs to reference trajectories. The architecture employs a novel composite observer structure, coupled with a robust adaptive controller that features integral sliding surfaces. This method enables precise state estimation and continuous control action while reducing chattering effects. Key innovations include: 1) unified finite-time convergence of four critical control objectives - disturbance estimation, fault identification, observer stability, and speed regulation; 2) a subsystem decomposition strategy for efficient fault/disturbance identification; and 3) adaptive compensation mechanisms for estimation error mitigation. Numerical validation demonstrates the framework’s effectiveness in maintaining precise speed control under various fault scenarios and model- ing uncertainties. Comparative results show significant improvements in transient response and disturbance rejection over existing methods, particularly in applications demanding high reliability and rapid response times.