Smc And Pi Disturbance Compensation Techniques By Using Nonlinear Speed Control For Pmsm System
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SMC and PI Disturbance Compensation Techniques By using Nonlinear Speed Control for PMSM System
ABSTRACT: In order to optimize the speed-control performance of the permanent-magnet synchronous motor (PMSM) system with different disturbances and uncertainties,. In further improve the disturbance rejection performance of SMC method, extended sliding-mode disturbance observer (ESMDO) is proposed, and the estimated system disturbance is considered as the feed forward compensation part to compensate sliding-mode speed controller. Thus, a composite control method combining an SMC part and a feed forward compensation part based on ESMDO, called SMC+ESMDO method, is developed. First, a sliding-mode control method based on one novel sliding-mode…show more content… In these nonlinear control methods, SMC method is well known for its invariant proper-ties to certain internal parameter variations and external disturbances, which can guarantee perfect tracking performance de-spite parameters or model uncertainties. In a novel exponential reaching law was presented to design the speed- and current-integrated controller. To suppress chattering problem, system variable was used in this reaching law.1-2 However, in the aforementioned reaching laws, the discontinuous gain rapidly decreases because of variation of the functions of the sliding surface, thus reducing the robustness of the controller near the sliding surface and also increasing the reaching time. 3-4In order to solve the aforementioned problems, a novel reaching law, which is based on the choice of an exponential term that adapts to the variations of the sliding-mode surface and system states, is proposed in this paper. This reaching law is able to deal with the chattering/reaching time dilemma. Based on this reaching law, a sliding-mode speed controller of PMSM is developed.
2. LITERATURE REVIEW
During the last decade, permanent magnet synchronous motors have been used widely in the industry to replace DC motors and induction machines. The main characteristics of these motors are the low inertia, the high efficiency, power density and reliability. Due these