Equipping output filters can effectively reduce the stator current harmonic content and output voltage rate of change (du/dt) of high-speed permanent magnet motor drives. However

under high-power and low carrier ratio conditions

traditional L

LC

and LCL filters are larger in size. This paper applies LLCL filters to high-speed permanent magnet synchronous motors to reduce the volume

and proposes a resonance suppression method suitable for LLCL filters. The proposed controller is implemented by state feedback of the inverter output voltage and motor current

without additional sensors. Parametric design is realized based on the discrete domain model

and a detailed coefficient selection method is given to quickly and effectively complete the design of the resonance suppression controller. Theoretical analysis and experimental results show that compared with the LCL filter

the LLCL filter effectively reduces the output filter volume as well as weight. The proposed resonance suppression method can effectively suppress the resonance of the LLCL filter without additional sensors

and has good parameter robustness.