| 摘要 |
PROBLEM TO BE SOLVED: To improve a protective function for a power system by surely operating a distance relay of an accident phase in the case of an accident.SOLUTION: A protective relay device comprises: an accident detection circuit for detecting a phase, among a plurality of phases, including a transmission line in which an accident occurs; and a plurality of distance relays which are provided for each of the phases and to which a standard setting value is preset for breaking a cable way of the transmission line by assuming an accident to occur in the transmission line. The distance relay of a phase that is judged as an accident phase by the accident detection circuit is switched from the standard setting value to an extension setting value for which arc resistance to occur at an accident point is taken into account and which is greater than the standard setting value.SELECTED DRAWING: Figure 1 |
