Wavelet Power Based Transformer Internal Fault Protection Algorithm

This paper presents a novel wavelet power based algorithm for protection of transformers during an internal fault. The proposed protection algorithm was first announced for protection of stator windings of a three-phase synchronous generator. It is based on the calculation of wavelet powers of primary voltage and current samples. Wavelet powers of each phase are calculated by using detail coefficients of the analyzed signals. A three phase-two winding transformer is used for laboratory experiments. The results validate the efficiency of the proposed algorithm.