Faulted segment identification in multi-phase distribution systems using sequence component modeling

This article discusses the potential for identifying faulted segment(s) on multi-phase distribution primaries using sequence component modeling and standard three-phase short-circuit solvers. Identifying faulted segments in a timely manner speeds up fault isolation and restoration processes, contributing to greater feeder reliability. The methodology utilizes fundamental frequency current magnitudes from the feeder head in conjunction with an approximate sequence model of the multi-phase feeder including single-phase and double-phase line segments augmented with dummy lines. Under certain fault conditions, multiple faulted segments may be yielded for which a new faulted segment reduction method based on voltage sag data is proposed. The Saskpower network simulated in MATLAB/Simulink (The MathWorks, Natick, Massachusetts, USA) environment was used to evaluate the faulted segment identification and reduction methods. The evaluation studies show quite promising results in uniquely identifying the actual faulted segment with reduced measurement and modeling requirements.