| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress a communication-disabled range of a digital protection relay to the minimum even if abnormality occurs in a transmission path. <P>SOLUTION: A digital protection relay device with a communication function includes a central monitoring system 13 monitoring/controlling an electric amount of a main circuit system becoming a protection object, a HUB 14 connected to the central monitoring system 13 and a plurality of digital protection relays 1a, 1b and 1n connected to the HUB 14. Communication circuits 11a, 12a, 11b, 12b, 11n and 12n of the plurality of digital protection relays 1a, 1b and 1n are connected by the transmission path 15 in a loop form. <P>COPYRIGHT: (C)2010,JPO&INPIT |
