IDENTIFICATION OF LOW FREQUENCY MODES USING WAVELET ANALYSIS

Abstract

In this report, low frequency modes of power system are identified by means of wavelet analysis. Major concern of this work is on identification of inter area modes on inter-tie line of power system. Continuous wavelet transform based technique has been used to determine the properties of a mode of power signal, which can be given by determination of modal frequency and damping of the given inter tie power signal. For this technique Complex Morlet wavelet is used as a type of wavelet. It is necessary to select a proper value of the bandwidth parameter, center frequency parameter, translation parameter and scale parameter to get accurate results. For this parameter selection purpose several guidelines have been discussed in the report. The proposed technique has been applied on two mode synthetic test signal and Modified Two area Four machine power system to find out inter area modes on inter tie lines. In Five area 16 machine power system, local mode and inter area modes both the modes have been identified using the proposed technique. Performance of the proposed technique has been checked by using eigen value analysis.