Ac Permanent Magnet Synchronous Motor Torque Ripple Suppression Control Strategy Study

The tendency of modern AC servo systems is high efficiency, high performance and low cost. Permanent magnet synchronous motors are widely used in AC servo system as actuators for the advantage of simple structure, small sizes, high efficiency, reliable operation, wide speed range and good dynamic/static characteristics, etc. However, as the existence of the parasitic torque ripple, there are limitations in some application for the demand of high-precision. Meantime, the torque ripple leads to the speed ripple.The problem of torque ripple of engineering applications is analyzed in this paper, and it is found that these torque ripples vary periodically, and the theoretical analysis is given. The model of permanent magnet synchronous motor control system is established based on vector control theory.The scheme of current study-compensation is proposed and applied for suppression of periodic torque ripple based on iterative learning control theory. Simulation results demonstrate the effectiveness of the proposed control scheme.A fuzzy-PI controller for parameter self-tuning of the speed-loop is designed based on fuzzy logic, in which control parameters can be modified on-line according to expert experience and rules. Simulation results show that the settling time of the system is reduced and the dynamic/static performance of the system is improved obviously, and the demands of high-performance are satisfied via the fuzzy-PI control strategy.