Current differential relaying coping with communications channel asymmetry
Gustavo Brunello, Bill Premerlani, Ilia Voloh · 2004
This paper describes a GPS based mechanism to guarantee reliable operation of current differential relays under channel asymmetry conditions. Topics discussed in the paper include: 1) types of digital communication used for line differential relays: direct optic fiber, multiplexers and Sonet/SDH communications systems, 2) relay clock synchronization when the communication channel is symmetrical, 3) the use of GPS time signal for sample synchronization during asymmetrical communication conditions , 4) fallback strategies for line differential relays under GPS/ communications contingencies.