Comparative Analysis of Static Eccentricity Faults of Double Stator Single Rotor Axial Flux Permanent Magnet Motors

This paper studies the impact of static eccentricity faults on a double stator single rotor (DSSR) axial flux interior permanent motors (AFIPMs) by using 3-D finite element (FE) analysis. Eccentricity in DSSR motors can lead to mechanical faults and vibrations. However, eccentricity fault detection method for DSSR AFIPMs have not been studied before. In this paper, three types of static eccentricity named angle, space and combination of angle and space eccentricity have been modeled in a DSSR AFIPM by using 3-D FE analysis. After that, the motor was simulated for different degrees of static eccentricity. Different performance parameters such as torque, air gap flux density and back electromotive force (BEMF) of the coils for all three types of static eccentricities have been analyzed for different eccentricity levels. This study indicates that the lower order harmonics of BEMF can be effectively used to identify and compare the types of static eccentricity present in the DSSR type AFIPMs.