A Formal Language Approach in Fault Location on Distribution Power Systems

This paper presents a Clarke-Concordia transformation approach, combined with formal language theory, within fault diagnosis for distribution power lines. The alpha, beta, 0 components of line currents, resulting from the Clarke-Concordia transformation, are used to detect and classify all types of fault. The formal language approach is used to map the non-linear relationship existing in fault location equations. The proposed approach is able to identify and to locate all different types of faults (single line to ground, double line to ground, line-to-line and three-phase short-circuit). This approach is subdivided into several main steps: first is the data acquisition of the corresponding current signals; then the mathematical computation of the Clarke-Concordia components; the fault identification is then performed by the analysis of fault and pre-fault data; finally the fault location estimation using a formal language theory based algorithm. Results are presented to reveal the effectiveness of the proposed algorithm for a correct fault location on distribution power lines.