Fault Analysis of 3-Phase Cage Induction Motor Based on Winding Function Theory

This paper studies on the fault analysis of 3-phase squirrel-cage induction motor with the rotor static eccentricity, the broken rotor bars, and the mixed fault at steady state. A mathematical fault model is presented by the coupled magnetic circuit approach. The Calculation of winding inductances is derived by means of a winding function theory. The concentrated winding type and the uniformly distributed winding type are used to taken into account the stator slot width effect. It is known that the calculation results of inductances of the concentrated type and the uniformly distributed type are almost similar. From the simulation results it is shown that there is its own peculiar frequency component obtained by the spectrum analysis of the stator current in the case of a single fault. But in the case of mixed fault, there is a mutual effect between two faults. From the comparison with FEM results, it is shown that the proposed approach can be simulated to diagnose faults in 3-phase squirrel-cage induction motor.