Motor Current Signature Analysis for Identification Induction Motor Defects

The paper considers the application of the method of motor current signature analysis (MCSA) for the most common faults in induction motors: interturn short circuit in the stator winding, shaft eccentricity, disalignment of coupling between the motor shaft and the load, bearing races wear, rolling bearing cage damage, inner ring damage of the rolling bearing, outer ring damage of the rolling bearing, rolling elements damage. Such defects introduce changes in the harmonic composition at pre-calculated frequencies, which are determined by the supply network frequency, rotor speed, and fault coefficients. The method involves the study of the spectral dependence of the motor stator current in the presence of faults compared to a efficient one. Decryption the results of the spectral analysis of the measured current will make it possible to determine the type of fault with a high probability, and with further improvement of the approach, to predict its potential occurrence. An algorithm for determining characteristic frequencies of faults using the MCSA tool is developed. Digital modeling results confirming the approach's effectiveness are presented.