리스크정보를 활용한 비상디젤발전기 허용정지시간 연장시 안전성평가

Safety Assessment for Emergency Diesel Generator(EDG) Allowed Outage Time(AOT) Extension using Risk-informed

  • Lim, Hyuk-Soon (Reliability Engineering Team, Nuc1ear Engineering & Technology Institute) ;
  • Kim, Doo-Hyun (Department of Safety Engineering, Chungbuk National University)
  • 투고 : 2010.01.04
  • 심사 : 2010.06.18
  • 발행 : 2010.06.30

초록

원자력발전소의 운전 유연성 증대, 안전성 및 경제성 향상, 정비 부담을 완화하기 위해 비상디젤발전기의 허용정지시간 연장이 요구된다. 확률론적안전성평가(probabilistic safety assessment) 기법으로 현재의 비상디젤발전기의 허용정지 시간을 3일에서 7일, 10일, 14일로 연장시 안전성 영향을 평가하였다. 종합적으로 평가결과, 비상디젤발전기의 허용정지시간 연장시 EDG 점검 또는 정비기간 중 인적실수으로 인한 발전소 불시정지 예방 및 안전성을 향상 시키는 것으로 분석되었다.

In order to provide the necessary operation flexibility during the Nuclear power operation, the extension of existing allowed outage time(AOT) is needed. The extension of AOT affects the Nuclear power plant safety. The validity of changed technical specification requirements should be proved by the safety assessments. In this paper, we evaluated the extension of emergency diesel generator AOT for a single inoperable emergency diesel generator(EDG) from 3days to 7days, 10days and 14days. Finally, the AOT extension contributes the NPP performances through decreasing the unexpected plant trips, reinforcing maintenance and avoiding risks due to unnecessary operation mode changes when the NPP is under the surveillance tests or maintenance.

키워드

참고문헌

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  5. USNRC, An Approach for Plant-Specific, RiskInformed Decision-making Technical Specifications, Regulatory Guide 1.177, 1998.