Capacitor–Voltage–Sensorless Resonance Damping and Harmonic Suppression Control for LCL-Equipped HSPMSM Drives With Capacitively Coupled Active Damper

This article proposes a resonance damping and harmonic suppression control method without capacitor voltage sampling for inductive-capacitive-inductive third-order (LCL) filter-equipped high-speed permanent magnet synchronous motor (HSPMSM) drives with a capacitively coupled active damper. The proposed method only needs to sample the motor current, and the resonance damping and harmonic suppression are achieved through the state feedback of the motor current. The proposed method can effectively suppress the resonance of the LCL filter and reduce the harmonics of the motor current, which not only saves the sensors but also has a better harmonic suppression effect compared with the method based on capacitor voltage sampling. The proposed method has been experimentally demonstrated to reduce the motor current harmonics by more than 30%.