Optimized Fast Terminal Sliding Mode Control for Permanent Magnet Synchronous Motor Drives Speed Regulation

Permanent Magnet Synchronous Motors (PMSMs) are widely used in precision drive systems due to their high efficiency and compactness; however, nonlinear dynamics and external disturbances pose challenges for accurate speed regulation. This paper proposes a Particle Swarm Optimized Fast Terminal Sliding Mode Control (PSO-FTSMC) scheme for PMSM speed regulation. The Fast Terminal Sliding Mode (FTSM) structure ensures finite-time convergence and robustness against uncertainties and disturbances, while Particle Swarm Optimization (PSO) is employed offline to automatically tune the controller parameters by minimizing a composite integral performance index. A comparative evaluation is conducted against conventional Terminal Sliding Mode Control (TSMC) under identical PMSM parameters and load disturbance conditions. Simulation results demonstrate that the proposed PSO-FTSMC achieves faster convergence, lower overshoot, and reduced chattering, with a smoother control effort, compared to TSMC.