Discrete-Time Internal Model Current Regulator With Active Resistance and Repetitive Control for Disturbance Suppression of High-Speed PMSM

The discrete-time internal model current regulator is characterized by simple parameter tuning and excellentd- andq-axis current decoupling performance. It shows promising potential for application to the high-speed permanent magnet synchronous motor (HSPMSM). However, the current control performance of the HSPMSM is deteriorated by various dc and ac disturbances. As a solution for suppressing dc disturbances, active resistance (AR) is typically incorporated into the current feedback control loop. Nevertheless, AR fails to suppress ac disturbances. In fact, it produces the opposite effect, resulting in an increase in the total harmonic distortion (THD) of the current. To address this issue, a discrete-time internal model composite current regulator with AR and repetitive control is proposed. First, AR is introduced into the current feedback control loop to suppress dc disturbances. Then, a repetitive controller is designed to operate in parallel with the AR controller to compensate for ac disturbances. Theoretical analysis of the proposed current regulator is performed in this paper, its stability is proved, and parameter tuning principles are provided. Finally, the effectiveness of the proposed method is verified through experiments in comparison with conventional methods.