Detection and Classification of Bearing and Single Phasing Faults of a Squirrel-Cage Induction Motor using Wavelet Transform

Abstract

This paper describes a protection scheme for a 3phase induction motor to detect and classifingthe bearing faults and single phasing faults. The loyalty of an Asynchronous induction motor is of predominant importance in various applications like industrial, commercial, aerospace and military.. Rotating mechanical part bearings played an important role in the reliability and performance of all motor systems. In this paper the 3phase stator current signals are captured in P.C using DIP8000 that is having a sample frequency of 5.3KHZ. These signals are analyzed with Bior5.5 wavelet and decomposed up to 5th level. The values of d2 coefficient is above the predefined value of Threshold1 (th1) then the motor is under fault. In case of bearing faults all these values are above the predefined threshold otherwise it is healthy. The phase which is above Th1 represents the single phasing fault on that phase.
Keywords: bearing fault, sampling frequency, Threshold and Wavelet Transform.