Sources and characteristics of unbalanced magnetic pull in 3-phase cage induction motors with axial-varying rotor eccentricity

Abstract

This paper puts forward a model for assessing UMP due to rotor eccentricity in cage induction motors that takes into account axial variation in the eccentricity. It is tested using 10-pole and 4-pole machines with some experimental results validate the model. The paper assesses the effect of bar number and variable-frequency operation on the UMP and highlights key points for generation of UMP in cage induction motors. Both dynamic and static eccentricities are studied.