Generalized Adaptive Disturbance Observer Based Global Terminal Sliding Mode Control for PMSM With Measurement Noise

Improving the robustness and dynamic response of permanent magnet synchronous motor (PMSM) drive systems with measurement noise has become one of the research focuses. Aiming at this issue, a generalized adaptive disturbance observer (GADO) based global terminal sliding mode speed control (GTSMC) scheme is proposed for PMSM. Firstly, a novel terminal sliding surface ensuring that the initial system operates in sliding mode is introduced, and the GTSMC controller is thus derived. Further, a current decoupling controller based on the linear extended state observer (LESO) is designed to realize the accurate dynamic decoupling. Regarding the undesirable chattering of GTSMC, a disturbance attenuation scheme based on generalized adaptive disturbance observer (GADO) is proposed. The uncertain disturbances are estimated by the GADO, and equivalent compensation is introduced. Different from the conventional fixed-gain disturbance observer, the influence of measurement noise is considered and the generalized adaptive gain mechanism is introduced to the GADO. The gain of the GADO can be adaptively adjusted according to the operating state, in which the excellent dynamic response and low sensitivity to measurement noise are guaranteed. Finally, the proposed control scheme for PMSM are tested through simulation, and the results verify its excellent performances in terms of speed tracking, robustness against uncertainties, and sensitivity to measurement noise.