Capacitively Coupled Active Resonant Damper for HSPMSM equipped with LCL filter

This paper proposes a capacitively coupled active resonant damper to suppress the resonance of the LCL-equipped HSPMSM drives. The active resonant damper is connected to the system through the capacitor of the LCL filter. The power device of the proposed damper is a high-frequency low-power SiC-MOSFET tube. The proposed method does not require any additional sensors or a high-bandwidth current controller, only motor current feedback is needed to control the active damper. The design method of the feedback controller is given in detail.By applying the proposed active resonant damper, the limitations of the crossover frequency of the LCL filter and the Nyquist frequency of the driver are weakened. For example, the crossover frequency can even be designed to be greater than the Nyquist frequency. Thanks to this, the size of the filter can be greatly reduced and the design of the motor controller is more flexible. The experimental results of a 3kW-12kr/min(1000Hz) test motor verify the effectiveness of the proposed method.