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Detection of Static Air-Gap Eccentricity in Three-Phase Squirrel Cage Induction Motor Through Stator Current and Vibration Analysis

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Abstract

Three-phase squirrel cage induction motor being a core component of industrial drives needs fault detection strategies which can detect internal faults in very early stage of its development. This can result in enormous financial saving in industries. Simulation studies with suitable mathematical models helps in identification of fault signatures in the diagnostic signal. The work presented in this paper addresses the issue of detection of incipient static eccentricity faults. Modelling of motor with static eccentricity fault is done and characteristic signatures were identified in frequency spectrum of stator current. These components were also identified in the vibration spectrum, by conducting a practical experimentation in three-phase squirrel cage induction motor with fabricated static eccentricity. The results validates the modelling approach and also demonstrates the suitability of vibration and stator current signal for the diagnosis of incipient static eccentricity faults.

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... It indicated that the voltage spectrum of the neutral point was more sensitive to the air-gap static eccentricity. Bindu and Thomas (2018) proved the applicability of the vibration signal and stator current signal in diagnosing static eccentricity through experiments on three-phase squirrel-cage asynchronous motors with static eccentricity. Ding et al. (2015) studied the influence of different air-gap static eccentricity on magnetic field strength and core loss based on electromagnetic theory and the finite-element method. ...
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