A new multiterminal fault location algorithm embedded in line current differential relays

Accurate fault location on transmission lines becomes increasingly beneficial by reducing outage times and allowing faster restoration of scarce power system assets back into service. Having natural access to synchronized remote current data, line current differential protection schemes can incorporate multiterminal fault location algorithms, allowing for more accurate fault location compared with single-ended methods. This paper describes a new algorithm for fault location for two-, three-, and four-terminal lines suitable for integration in a typical line current differential scheme. The paper presents the new algorithm in detail, includes examples of its operation, and presents test results based on simulations as well as some application considerations related to the loss of communications or data synchronization between the 87L scheme relays.