Differential Protection of Power Transformer using Wavelet Transform

Abstract

 Abstract: This paper presents wavelet transform method for the analysis of differential currents of power transformer which can act as an accurate classifier between magnetizing inrush current and internal faults to avoid the needless tripping of circuit breaker. The differential protection scheme occasionally maloperate whenever magnetizing inrush occurs in power transformer. The aim is to reduce the rate and time duration of undesired outages of power transformer. This includes the necessities of reliability with zero maloperation of differential relay. The result shows higher operating speed with less fault clearing time. Wavelet Transform is employed for the analysis of transient signals under various conditions, which extracts data from signals in time and frequency domain simultaneously. The simulation is done in MATLAB environment.

New Method for Transient Signal Analysis using the Continuous Wavelet Transform

“…The effectiveness of WT in transient analysis has led to its combination with other techniques to enhance the reliability of detection schemes [18]. Furthermore, WT has been used successfully to extract important information from transient signals in both the time and frequency domains, aiding in fault diagnosis and condition detection [19,20].…”