A diagnosis procedure in standstill mode for inter turn short circuit faults of PMSMs through modified self-commissioning

In this paper, an comprehensive impedance analysis is proposed to detect inter turn short circuit fault in PMSMs at start-up. This method requires a very small computational load (less than 5% CPU bandwidth) and is easy to implement. The procedure is performed at start-up during standstill mode, and hence agnostic to well-known issues caused by transients, load/speed level or controller coefficient dependency. In order to distinguish the inter turn shorts from the eccentricity fault which exhibits similar behaviors, a classification algorithm is introduced based on stator resistor and inductances. Moreover, the effect of stator iron core saturation on the electric parameters analyzed in depth. Both 2-D FEA simulation and experimental test results are provided to show the efficacy of this method.