| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable a standard communication system by enabling the reduction of the transmission speed of the sampled data of each terminal transmitted between counter terminals. <P>SOLUTION: A current differential protective relay device is installed in each terminal of a power system constiuted by linking a plurality of terminals by a transmission line, and performs protective operation by transmitting the data created by sampling each phase of currents of each terminal in fixed cycles, based on a sampling synchronization signal, and converting them into digital between each terminal and the next. The relay device possesses an orthogonal quantity operation part 9 which gets two mutually orthogonal quantities expressing the current vectors of each phase from a plurality of current data sampled in fixed cycles, a transmission part 8 which transmits and receives the two orthogonal quantities obtained by the orthogonal quantity operation part 9 between counter electrodes, an operation part 6 which determines the existence of the occurrence of the trouble of the transmission line by differential operation from the two orthogonal quantities transmitted from its own end and the counter end obtained by the orthogonal quantity operation part 9, and an output part 7 which sends out a specified output, based on the determination results of the operation part. <P>COPYRIGHT: (C)2004,JPO |
