Advancements in Digital Protection of Power Transformers

This paper presents a brief introduction to the emergence of differential protection of power transformers. In this paper, the techniques used in implementing the 2^nd harmonic restraint, the artificial neural network (ANN) and the latest wavelet packet transform-based disturbance detection and classification are reviewed. Moreover, the response of these different protection techniques is simulated for the same conditions. Finally, a comparison between these techniques is made and to identify the technique that offers the optimal power transformer protection. A list of references provide a state-of-the-art survey of significant as well as some incremental contributions in chronological order of appearance over the past 50 years.