Utilities across the world are using traveling-wave-based (TW-based) devices to locate faults with an accuracy of one to two tower spans. This paper briefly discusses capabilities of line protective relays that include TW-based functions such as fault locating, line monitoring, and a line current differential scheme (TW87). The paper includes a tutorial on Vaisala’s National Lightning Detection Network and lightning detection sensors. The paper shows how the time stamp reported from a lightning-detection system correlates to the TW arrival time reported by the line protective relay for lightning events.
The paper discusses two lightning strikes captured in the field: one that hits only the shield wire and another that hits both the shield and phase conductors, creating a temporary fault. The paper discusses how the correlation of data from the lightning-detection network and the relays helps the patrol crew to locate the disturbance. PPL Electric Utilities Corporation uses this correlation to confirm the root cause of the disturbance and to verify performance of the lightning mitigation devices in the network.
In addition to fault locating and line monitoring, TWs are used for line protection applications, and this paper presents the performance of the TW-based line protection functions for these lightning events.