Fault location estimation for transmission lines using voltage sag data

This paper presents a general approach to locate any type of fault on either a single-circuit or a double-circuit transmission line when only voltage sag data are available. The voltage measurements employed can be from one bus, two buses, or more buses, which are not restricted to those of the faulted section. It is assumed that the network data are available and the fault type is known. Quite encouraging results have been obtained based on EMTP simulation studies.