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

Abstract

In this paper a method is proposed which enables the detection of the air-gap eccentricity in induction machines at an early stage. It is shown that by proper modeling of the induction motor it is possible to detect the effect of eccentricity on the machine line currents, whether the machine is running off a sinusoidal supply or a converter. The effect of eccentricity on the machine current signature is discussed. Theoretical foundations of the technique, as well as the detailed differential equations describing the machine performance under rotor eccentricity are presented.