Harmonic Current Regulation of SMPMSM by Discrete-Time Current Controller Design

A discrete-time domain design of a harmonic current controller based on multi-reference-frame-control (MSRF) is proposed for the suppression of the torque ripple of surface mounted permanent magnet synchronous motor (SMPMSM). The design criteria for the open-loop transfer function are established by modeling the motor plant and proposed controller in the discrete-time domain, and the controller gains that satisfy these criteria are obtained using matrix calculations. The proposed controller's effectiveness is confirmed through experimental validation. The phase margin and bandwidth of the controller designed in the discrete-time domain have been noticeably enhanced compared to that designed in the analog domain.