To provide a transfer cutoff type transformer protective relay system having a new configuration, the relay system suppressing a delay in accident elimination as much as possible.
The transformer protective relay system includes primary and secondary photocurrent sensor groups 6a and 6b which detect primary and secondary phase currents from a transmission 4 disposed in an incoming substation 2 supplied with power from a transmission substation 1 via a transmission line 3, primary and secondary optical fiber transmission paths 7a and 7b through which output from the photocurrent sensor groups 6a and 6b is optically transmitted to the transmission substation, primary and secondary photoelectric converters 8a and 8b which are disposed in the transmission substation and receive optical signals from the optical fiber transmission paths 7a and 7b to convert the optical signals into voltage signals, and a transformer protective ratio differential relay device 9 which opens a breaker 5 placed on a system supplying power to the incoming substation, based on output voltages from both photoelectric converters 8a and 8b.
KUROSAWA KIYOSHI
OSAKO YUJI
YAMADA TOSHIHARU
ITAKURA EIJI
KANSAI ELECTRIC POWER CO
TAKAOKA ELECTRIC MFG CO LTD