A method for dynamic simulation of air-gap eccentricity in induction machines

In this paper, a method is proposed which enables the simulation of the air-gap eccentricity in induction machines. The method is based on the coupled magnetic circuit approach. The model is derived by means of winding functions, and no symmetry in windings layout is assumed. The parameters of the model are calculated directly from the geometry and winding layout of the machine. The effect of eccentricity is included in calculation of machine inductances. It is shown that by proper modeling of the induction motor it is possible to determine the effect of eccentricity on the machine startup, whether the machine is running off a sinusoidal supply or a converter. Theoretical foundations of the technique, as well as the detailed differential equations describing the machine performance under rotor eccentricity are presented.