An accurate algorithm for fault distance estimation of two-parallel transmission line based on one-terminal sampling

An accurate numerical algorithm of fault location estimation for triple line-ground fault involving different phases from each of two-parallel lines is presented in this paper. It is based on one-terminal voltage and current data. The loop and node equations comparing faulted phase to nonfaulted phase of two-parallel lines are introduced in the fault location estimation modal, in which source impedance of remote end is not involved. The effect of load flow and fault resistance are effectively eliminated on the accuracy of fault location, therefore an accurate algorithm of locating a fault is derived. The algorithm is demonstrated by digital computer simulations.