Various parameters influence on field distribution in eccentric disc-type permanent magnet machine based on analytical method

Abstract

ABSTRACT Eccentricity fault is a common fault in axial flux permanent magnet (PM) machines that can be destructive. The finite element method (FEM) has been already used for modelling eccentricity fault in disc type PM machine. Applying three-dimensional (3D) FEM to this motor is essential. However, 3D-FEM is a very time-consuming technique. Therefore, it is more appropriate to use an analytical technique to investigate the impact of different parameters upon the motor’s performance. The existing analytical methods usually represent a qualitative overview of the faulted machine. In this paper, a precise and quick analytic method is introduced, reflecting the impact of various important parameters, including rotor angle and fault position on the motor’s performance. This method enables the calculation of the induced voltage in a search coil. Comparing the results obtained from the proposed method and FEM, in both the no-load and full-load conditions, confirms the method’s accuracy. Finally, the impact of the search coil’s various parameters on dynamic and static eccentricity faults is examined. In addition, choosing the proper search coil pitch for eccentricity faults detection is discussed.