Modeling eccentricity faults with axial asymmetry in three-phase induction motors

Abstract

Squirrel cage induction motors (SCIMs) have gained critical roles in many industries. Most mechanical faults cause eccentricity within the SCIMs, so, it is important to develop reliable eccentricity fault diagnosis systems. Modeling and simulation of the eccentricity faults can help to reach this aim. This paper proposes modeling and simulation of the eccentricity faults with variable degrees along the axial length of the induction motor. Multiple coupled circuits model with 2-D modified winding function theory are used for this purpose. Simulation results show that having the same risk of rubbing the stator by the rotor, the axially asymmetric eccentricity (inclined eccentricity) creates lower fault indices, so, considering the higher occurrence probability as well, it is reasonable to design the fault diagnosis systems based on the inclined eccentricities.