RELAY-TO-RELAY DIRECT COMMUNICATION SYSTEM IN AN ELECTRIC POWER SYSTEM

摘要

The system provides communication of information between at least two protective relays (10, 12) serving a power system line (14). The communicati on comprises a series of successive data messages of four characters, each of which includes eight data bits, on eight data channels. The data bits includ e output function status bits from the transmitting relay (10) on user selecte d channels, and virtual terminal data bits on still other user selected channels. A synchronization channel (30) produces information to synchronize the transmission/receiving of the analog data and the virtual terminal data, on the basis of frames of data, each frame containing 18 messages.