An application of relay-to-relay logic communications for single pole tripping

This paper describes the application of a permissive overreaching transfer trip (POTT) system to protect a double circuit transmission line for which single pole tripping and reclosing was required to ensure power system stability. Application of the advanced relay-to-relay logic communications (a.k.a. mirrored bit logic) in the numerical relays provide a solution to the cross-country fault problem. This new technology also reduces the overall complexity and equipment costs.