Impact of the Stator Short-circuit, Rotor Broken Bar and Eccentricity Faults on Rotor Force for Loaded and No-load Induction Motors Operation

Based on finite element analysis in time domain of a squirrel cage induction motor this paper studies the influence of the three faults - stator short-circuit, broken rotor bar and static eccentricity on the mean values and harmonics of the rotor unbalanced force. Results for loaded motor operation and for no-load motor operation are compared. The healthy state of motor operation and seven faulty cases, with single, double and triple faults, are considered. All faulty cases are characterized by important increase of the rotor force compared with the healthy case.