Field experience using double-ended traveling-wave fault locating without relay-to-relay communications

This paper discusses how Red Eléctrica de España, the transmission system operator in Spain, successfully applied double-ended traveling-wave-based fault locating (DETWFL) on a pilot project where relay-to-relay communications were unavailable. When relay-to-relay communications are unavailable, an offline DETWFL methodology may be used, in which traveling-wave (TW) arrival time information is manually collected from time-synchronized relays at both ends of the line after an internal fault occurs and the fault location is computed. The paper describes the offline DETWFL method and includes an analysis of a B-phase-to-ground fault on a transmission line to illustrate the performance of this method. It provides a summary of results from five faults that occurred on this line while relay-to-relay communications were unavailable.