Vibration Suppression for Dual Three-Phase PMSM With Open-Circuit Fault

The dual three-phase permanent magnet synchronous motor (PMSM) is featured with intrinsic fault-tolerant capability. However, the vibration performance under the fault condition has rarely been investigated. The unbalanced armature magnetomotive force under the open-circuit fault condition results in the deteriorated vibration performance, inevitably. In this paper, the vibration performance under the open-circuit fault condition is analyzed. The theoretical analysis demonstrates that the vibration occurs at the even multiple of the fundamental frequency. In order to suppress the vibration due to the open-circuit fault, the same armature magnetomotive force as the healthy condition should be achieved. The two parts of phase current reference can be determined by the principle of invariant magnetomotive force, respectively. Only the current reference in harmonic subspace need to be changed to suppress the vibration under the open-circuit fault condition. The proposed strategy is easy to be implemented in practice. A series of experimental results are given to confirm the effectiveness of the proposed method.