A Study on Fuzzy Sliding Mode Control of PMSM Based on Fractional-Order Extended State Observer

This study addresses the inherent trade-off between reaching speed and chattering in sliding mode control (SMC) of permanent magnet synchronous motors (PMSMs), while enhancing disturbance rejection under varying load conditions. A fuzzy sliding mode control strategy based on a fractional-order extended state observer (FOESO-FSMC) is proposed. First, fuzzy logic is utilized to adaptively adjust the constant-speed sliding mode reaching law, effectively suppressing chattering without compromising dynamic performance. Second, fractionalorder theory is integrated into the conventional extended state observer to construct a FOESO, enabling accurate real-time estimation and compensation of system uncertainties and load disturbances. Simulation results verify that the proposed strategy significantly improves both dynamic response and disturbance rejection capability.