Fault diagnosis of induction motor using wavelets

Abstract

Wavelet analysis is one the prime signal processing and data analysis techniques its ability to locate fault at exact duration is one of its added advantage in comparison to Fast Fourier transform in which time information of signal is lost .In addition to this FFT has another disadvantage that at low loads sidebands converges so it becomes difficult to detect the faults. STFT was proposed as a solution to resolution problem but its limited time-frequency resolution capability, because the uncertainty principle. Low frequencies can be scarcely depicted with short window that’s why wavelet theory is yet the most powerful tool in data analysis of signals. This paper presents a study of fault detection of induction motor like broken rotor bars stator short circuits using wavelets envelope analysis in which a signal is converted into approximate and detail signals thus removing the fundamental current which hides the fault harmonics present during faults