A permanent magnet synchronous motor speed control system based on fuzzy adaptive integral non-singular terminal sliding mode control

Abstract

To address the challenge of balancing vibration suppression and robustness in traditional integral non-singular terminal sliding mode control (I-NFTSMC) for permanent magnet synchronous motor (PMSM) speed regulation systems—where fixed gains often compromise these objectives—this paper proposes a fuzzy adaptive integral non-singular terminal sliding mode control (FA-I-NFTSMC) strategy. First, a mathematical model of the PMSM is established in the d-q synchronous rotating coordinate system. An improved I-NFTSMC controller is designed, employing a dual-gain saturation approach and incorporating a tracking error derivative term in the sliding mode surface to enhance dynamic response. Furthermore, a fuzzy adaptive mechanism based on absolute value normalization and an offline pre-generated lookup table is introduced to enable simultaneous dynamic adjustment of both sliding mode gains k1 and k2. Simulation results demonstrate that, compared to conventional I-NFTSMC, the proposed method achieves a 23.5% reduction in maximum speed drop under load disturbances, a 31.2% decrease in regulation time, and a 42.7% reduction in the ITAE composite performance metric—all while maintaining rapid response capabilities, thus markedly enhancing the system’s dynamic characteristics and anti-disturbance capability.