Adaptive Nonsingular Finite-Time Terminal Sliding Mode Control for Synchronous Reluctance Motor

Affected by the magnetic saturation effect and unmodeled dynamics, the parameters of the synchronous reluctance motor (SynRM) are highly nonlinear and time-varying. The resulting unreasonable current loop reference command severely restricts the maximum efficiency and high control performance of SynRM. Therefore, an adaptive non-singular terminal sliding mode control scheme for SynRM drive system is proposed to improve the dynamic performance and robustness. Firstly, an analytical model of flux linkage and inductance that satisfies the energy conversion mechanism is proposed to estimate the required parameters of the control system in real time. Secondly, a novel fast finite time adaptive-gain reaching law is proposed to shorten the arrival time while reducing the chatter near the sliding mode surface. Then, a non-linear disturbance observer is designed to estimate the total disturbance of the system. The asymptotic stability of the system is proved by Lyapunov's theorem. The experimental results demonstrate that the system has satisfactory dynamic performance and robustness.