An Accurate Fault Location Estimator for Transmission Lines

A fault location methodby dynamic system parameter estimation is presented for a double-end fed transmission line using a 1/4 to 1 cycle window of data at one local end only. The system differential equations are based on a lumped parameter line model, Thevenin equivalents for transients at both ends of the line and an unknown fault resistance. Simplification of the equations is obtained by using instantaneous symmetrical components. The estimation algorithm does not require filtering of d.c. offset and high-frequency components from the recorded signals and its accuracy is illustrated in digital simulation studies.