A novel fault classification technique for high speed protective relaying of transmission lines

This paper presents a new algorithm for faulty phase selection in transmission lines. The algorithm is based on a limited soft processing of the 3-phase and the zero-component current phasors. Current phasors are determined by using a pair of short length data window filters giving orthogonal outputs - phasor components. The soft processing means here that, generally, the operations like min and max are used rather than multiplication or summation of two or more arguments.