A DWT based differential relaying scheme of SVC compensated line

This paper discusses the fault classification and detection applying Discrete Wavelet transform (DWT) approach of differential relaying based SVC (Static Var Compensator) compensated transmission line. The SVC is located at middle part of transmission line. Fast detection of faults and fault classification helps restoration of supply, which enhances the economy and reliability of the power supply. SVC integrated line helps to improve reactive power compensation in transmission line. The current signals are retrieved from both end of the transmission line synchronously through CT's and processed with the help of DWT approach to compute Spectral Energy (SE) of each phase from both sending and receiving end of the transmission line. Then the Differential Spectral Energy(DSE) of each phase current signals are computed by subtracting the SE current signals obtained at sending end and the SE current signals obtained at receiving end of the transmission line. The evaluated DSE value of each phase current signifies the fault pattern identification and detection.