Overview on Transformer Protection Technology

Abstract: In this article, an attempt is made to put together developments in digital relays for protection of power transformer after 2000 year. Efforts have been made to include all the techniques and philosophies used to that end. The article includes the most recent techniques, like transformer saturation detection, harmonic usage, waveform processing and analysis techniques, various conversion methods, adding a series of electrical quantities to the differential current, and artificial neural network (ANN) and fuzzy logic concepts, as well as other conventional methods used for transformer protection. This article presents a set of references of all concerned papers and provides a brief summary of the work presented in them.