Complex Cepstrum based Analysis of Power Quality Events and its Comparison with Time-Frequency Analysis Methods

Abstract

Monitoring of events in the power system provides a great deal of insight into the behavior of the system. Power quality of electric power system has become an increasing concern for electric utilities and their customers over the last decade. The goal of monitoring non-stationary signal is to quantify the dynamic nature of these signals and to extract the important features that support the integrated monitoring system that can be used in maintenance scheduling and system operation. This paper documents an alternate method; Inverse Fourier Transform of a logarithmic spectrum called cepstrum has been used to analyze different power system events. Its performance has been compared with other time-frequency analysis methods like spectrogram, wavelet and scalogram. Cepstrum can detect the change in amplitude, frequency and phase accurately.