Optimal Fault Location Algorithm for Series-Compensated Transmission Lines Based on PMU Data

A new synchrophasor-based fault location algorithm for series-compensated transmission lines is presented in this paper. Both prefault and fault voltage and current phasors associated with either ends of a given line accessible through the phasor measurement units (PMUs) are taken as input data. The proposed algorithm initially estimates the line parameters using prefault data; thereafter, these parameters are used for estimating the fault location. This method is based on the positive-sequence equivalent p models of transmission lines, and since PMU can measure prefault and fault positive-sequence data in both symmetrical and unsymmetrical conditions, the method is applicable to all types of faults. The nonlinear weighted least square error (NWLSE) as a powerful method for tackling nonlinear estimation problem is used for the estimation process. Numerical case studies using MATLAB program demonstrate effectiveness of the new method.