A New Signal-Based Diagnosis Method for Current Sensor and Open-Circuited Faults of a Nine-Phase Open-End Winding PMSM

The current sensor faults (CSFs) and open-circuited faults (OCFs) are common for multiphase permanent magnet synchronous motor (PMSM) drives with open-end stator winding. Different faults often induce similar current characteristics, which increases the fault diagnosis difficulty. In this article, a new current signal-based fault diagnosis method is proposed to detect all kinds of CSFs and OCFs for multiphase PMSM drives, especially faults with similar current characteristics. First, the influence of the CSFs and OCFs on multiphase current signals is analyzed and compared. Second, a new current-based fault diagnosis method is proposed and the steps of its judgment criterion are illustrated. Furthermore, an adaptive algorithm is proposed, which can quantitatively describe the level of the faults. Finally, experimental results have verified the effectiveness and robustness of the proposed method, which accurately detects and locates all kinds of CSFs and OCFs for multiphase open-end winding PMSM drives.