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, or they could be unnecessarily conservative in their expression. Therefore, realistic assessment...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-07-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/14/14/4119 |
| _version_ | 1797527250697977856 |
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| author | Sejin Baek Gyunyoung Heo |
| author_facet | Sejin Baek Gyunyoung Heo |
| author_sort | Sejin Baek |
| collection | DOAJ |
| description | 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, or they could be unnecessarily conservative in their expression. Therefore, realistic assessment techniques are needed to adequately capture accident scenarios. In multi-unit probabilistic safety assessment (PSA), fault trees naturally become more complex as the number of units increases. In particular, when considering a shared facility between units of the electric power system (EPS), static fault trees (SFTs) that prioritize a specific unit are limited in implementing interactions between units. However, dynamic fault trees (DFTs) can be available without this limitation by using dynamic gates. Therefore, this study implements SFTs and DFTs for an EPS of two virtual NPPs and compares their results. In addition, to demonstrate the dynamic characteristics of the shared facilities, a station blackout (SBO), which causes the power system to lose its function, is assumed—especially with an inter-unit shared facility, AAC DG (Alternate AC Diesel Generator). To properly model the dynamic characteristics of the shared EPS in DFTs, a modified dynamic gate and algorithm are introduced, and a Monte Carlo simulation is adopted to quantify the DFT models. Through the analysis of the DFT, it is possible to confirm the actual connection priority of AAC DG according to the situation of units in a site. In addition, it is confirmed that some conservative results presented by the SFT can be evaluated from a more realistic perspective by reflecting this. |
| first_indexed | 2024-03-10T09:41:22Z |
| format | Article |
| id | doaj.art-9fa892a497fe465aa4835c1cdfef0681 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-10T09:41:22Z |
| publishDate | 2021-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-9fa892a497fe465aa4835c1cdfef06812023-11-22T03:40:22ZengMDPI AGEnergies1996-10732021-07-011414411910.3390/en14144119Application of Dynamic Fault Tree Analysis to Prioritize Electric Power Systems in Nuclear Power PlantsSejin Baek0Gyunyoung Heo1Department of Nuclear Engineering, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin-si 17104, Gyeonggi-do, KoreaDepartment of Nuclear Engineering, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin-si 17104, Gyeonggi-do, KoreaBecause 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, or they could be unnecessarily conservative in their expression. Therefore, realistic assessment techniques are needed to adequately capture accident scenarios. In multi-unit probabilistic safety assessment (PSA), fault trees naturally become more complex as the number of units increases. In particular, when considering a shared facility between units of the electric power system (EPS), static fault trees (SFTs) that prioritize a specific unit are limited in implementing interactions between units. However, dynamic fault trees (DFTs) can be available without this limitation by using dynamic gates. Therefore, this study implements SFTs and DFTs for an EPS of two virtual NPPs and compares their results. In addition, to demonstrate the dynamic characteristics of the shared facilities, a station blackout (SBO), which causes the power system to lose its function, is assumed—especially with an inter-unit shared facility, AAC DG (Alternate AC Diesel Generator). To properly model the dynamic characteristics of the shared EPS in DFTs, a modified dynamic gate and algorithm are introduced, and a Monte Carlo simulation is adopted to quantify the DFT models. Through the analysis of the DFT, it is possible to confirm the actual connection priority of AAC DG according to the situation of units in a site. In addition, it is confirmed that some conservative results presented by the SFT can be evaluated from a more realistic perspective by reflecting this.https://www.mdpi.com/1996-1073/14/14/4119dynamic fault treestation blackoutAlternate AC Diesel Generatormulti-unit |
| spellingShingle | Sejin Baek Gyunyoung Heo Application of Dynamic Fault Tree Analysis to Prioritize Electric Power Systems in Nuclear Power Plants Energies dynamic fault tree station blackout Alternate AC Diesel Generator multi-unit |
| title | Application of Dynamic Fault Tree Analysis to Prioritize Electric Power Systems in Nuclear Power Plants |
| title_full | Application of Dynamic Fault Tree Analysis to Prioritize Electric Power Systems in Nuclear Power Plants |
| title_fullStr | Application of Dynamic Fault Tree Analysis to Prioritize Electric Power Systems in Nuclear Power Plants |
| title_full_unstemmed | Application of Dynamic Fault Tree Analysis to Prioritize Electric Power Systems in Nuclear Power Plants |
| title_short | Application of Dynamic Fault Tree Analysis to Prioritize Electric Power Systems in Nuclear Power Plants |
| title_sort | application of dynamic fault tree analysis to prioritize electric power systems in nuclear power plants |
| topic | dynamic fault tree station blackout Alternate AC Diesel Generator multi-unit |
| url | https://www.mdpi.com/1996-1073/14/14/4119 |
| work_keys_str_mv | AT sejinbaek applicationofdynamicfaulttreeanalysistoprioritizeelectricpowersystemsinnuclearpowerplants AT gyunyoungheo applicationofdynamicfaulttreeanalysistoprioritizeelectricpowersystemsinnuclearpowerplants |