A robust control scheme for a permanent magnet synchronous motor with speed loop sample delay

This paper proposes a robust control scheme for a permanent magnet synchronous motor(PMSM) with speed loop sample delay. Due to the sample interval of speed loop is always longer than that of current loop in a PMSM drive system, some pulsation is introduced into d-q currents and the decoupling of d-q currents is imperfect. Furthermore, other problems such as unknown loads and changes in parameters make the PMSM system difficult to control. To compensate the speed loop sample delay, a speed prediction algorithm with an extended states observer has been developed. To enhance the robustness of the driver system, the active disturbance rejection control (ADRC) has been adopted. The simulation results have proved the usefulness and validity of the proposed control method.