Application of Dynamic Fault Tree Analysis to Prioritize Electric Power Systems in Nuclear Power Plants

Because the scope of risk assessments at nuclear power plants (NPPs) is being extended both spatially and temporally, conventional, or static fault trees might not be able to express failure mechanisms, they could unnecessarily conservative in their expression. Therefore, realistic assessment techniques are needed adequately capture accident scenarios. In multi-unit probabilistic safety (PSA), naturally become more complex as number units increases. particular, when considering a shared facility between electric system (EPS), (SFTs) that prioritize specific unit limited implementing interactions units. However, dynamic (DFTs) can available without this limitation by using gates. study implements SFTs DFTs for an EPS two virtual NPPs compares results. addition, demonstrate characteristics facilities, station blackout (SBO), which causes lose its function, assumed—especially with inter-unit facility, AAC DG (Alternate AC Diesel Generator). To properly model DFTs, modified gate algorithm introduced, Monte Carlo simulation adopted quantify DFT models. Through analysis DFT, it possible confirm actual connection priority according situation site. confirmed some results presented SFT evaluated from perspective reflecting this.