EMERGENCY POWER SUPPLY SYSTEM AND EMERGENCY INDEPENDENT POWER SUPPLY, FOR NUCLEAR POWER PLANT

PROBLEM TO BE SOLVED: To feed power to significant apparatuses in terms of safety of a nuclear power plant at abnormal time of a normal power supply system.SOLUTION: An emergency power supply system for a nuclear power plant includes: first level emergency power supply for supplying power in a level 1 state; and a second level emergency power supply 10 for supplying the power in a level 2 state. The second level emergency power supply 10 includes: a first rotary electric machine 16a electrically and directly connected to at least one of normal power supply and the first level emergency power supply; a second rotary electric machine 16b not being electrically connected and being mechanically connected to the first rotary electric machine 16a; a second level emergency bus bar 14 being electrically connected to the second rotary electric machine 16b via a circuit breaker 17a and feeding the power to an emergency load; and a backup generator 15 starting up in the level 2 and supplying emergency power to the second level emergency bus bar 14. 【課題】常用電源系統の異常時に、原子力発電所の安全上重要な機器に給電する。【解決手段】実施形態によれば、原子力発電所用非常電源システムは、レベル１の状態のときに電力を供給する第１レベル非常用電源と、レベル２の状態のときに電力を供給する第２レベル非常用電源１０とを有する。第２レベル非常用電源１０は、常用電源および第１レベル非常用電源の少なくとも一方と電気的に直接接続された第１の回転電機１６ａと、第１の回転電機１６ａと電気的には接続されておらず機械的には接続されている第２の回転電機１６ｂと、第２の回転電機１６ｂと遮断器１７ａを介して電気的に接続し非常時負荷に給電する第２レベル非常用母線１４と、レベル２の状態のときに起動して第２レベル非常用母線１４に非常時電力を供給するバックアップ発電機１５とを有する。【選択図】図２