Imbalanced Force Suppression Due to Static Eccentricity by Using Triple Three-phase Winding Motor

Abstract

Permanent magnet synchronous machines (PMSMs) are widely used in a variety of applications. The static eccentricity of the rotor is a common fault in the fabrication process. These faults cause imbalanced electromagnetic force and exert unexpected vibration and acoustic noise during the design process. In the worst case, it causes bearing or motor failure. This research investigates the impact of this fault on the temporal and spatial harmonic distribution of gap flux density and electromagnetic force. Moreover, a compensation method has been proposed to suppress imbalanced force due to static eccentricity by using a triple three-phase winding motor. By controlling the three inverters independently, the winding current of each group can be controlled. Therefore, the gap flux density and electromagnetic force in each group can be brought into a desired state. Therefore, the imbalanced electromagnetic force can be restored using this system. In this paper, the effectiveness of the proposed method is verified by Finite Element Analysis (FEA) and experiment.