Plant-Level Scenario-Based Risk Analysis for Enhanced Resilient PWR – SBO and LBLOCA

Abstract

This report documents the activities performed by Idaho National Laboratory (INL) during the fiscal year (FY) 2018 for the DOE Light Water Reactor Sustainability (LWRS) Program, Risk-Informed System Analysis (RISA) Pathway, Enhanced Resilient Plant (ERP) Systems research. The purpose of the RISA Pathway research and development is to support plant owner-operator decisions with the aim to improve the economics, reliability, and maintain the high levels of safety of current nuclear power plants over periods of extended plant operations. The concept of ERP refers to the combinations of Accident Tolerant Fuel (ATF), optimal use of Diverse and Flexible Coping Strategy (FLEX), enhancements to plant components and systems, and the incorporation of augmented or new passive cooling systems, as well as improved fuel cycle efficiency. The objective of the ERP research effort is to use the RISA methods and toolkit in industry applications, including methods development and early demonstration of technologies, in order to enhance existing reactors safety features (both active and passive) and to substantially reduce operating costs through risk-informed approaches to plant design modifications to the plant and their characterization.

Risk-Informed Safety Analysis for Accident Tolerant Fuels

“…This indicates the need in future work to perform high-fidelity calculations using, e.g., a coupled code system like RELAP5-3D and INL's BISON thermomechanical code. 74 Finally, recent activities that have been performed at INL to assess the performance of near-term ATFs for other DBA cases 28,75 produced a broader picture of the benefits derived from their introduction into a PWR. Results from these activities have also confirmed Outcomes 1 and 2, reported before.…”

Predicting power system reliability and outage duration including emergency response

“…Эти события восстановления можно рассматривать как «нормальные» или Тип 1 с β ~ 0,22 без дополнительных значительных повреждений или трудностей, например, при незначительных ледяных штормах, локальных пожарах и городских сбоях (отключение электроэнергии в Куинсе в штате Нью-Йорк [4,15]). Кроме того, «вероятность отказа рабочего места оператора при восстановлении мощности переменного тока» с использованием аварийных батарей и дизельных генераторов (ДГ) P(АС) ДГ после обесточивания АЭС была рассчитана в [21] для «представительного» большого блока питания. Наиболее приближенная к 9 точкам [21, Таблица 4-13] в) сильное землетрясение в северо-восточной части Японии и цунами вызвали обесточивание и потерю внешнего энергоснабжения на долгий период времени у 9 ядерных реакторов на Фукусиме [22,23].…”

“…4 также показаны результаты расчета более высокой (λ АС = 0,001) или низкой (λ АС = 0,01) частоты отказов аварийной или резервной систем. Для сравнения показаны результаты отключения АЭС с Типом 1 «нормальный» в виде короткой временной шкалы (β = 0,22) с использованием частоты отказов аварийных систем λ ~ 0,091, которая была получена из опубликованной статьи с расчетами отключения АЭС [21].…”

Risk-Informed Analysis for an Enhanced Resilient PWR with ATF, FLEX, and Passive Cooling

“…This section presents a risk-informed analysis on ATF with the same generic PWR plant SAPHIRE PRA model and the same INL Generic PWR (IGPWR) RELAP5-3D model used in FY 2018 activities (Ma & al., 2018). Loss of feedwater (LOFW) and SGTR accident scenarios are developed by reviewing the PRA model and then analyzed by RELAP5-3D code for near-term ATF designs, FeCrAl, and Cr-coated cladding.…”

“…The other was to investigate various approaches to accomplish the ERP research objective, i.e., use RISA methods and toolkit to enhance existing reactors safety features and reduce plant operating costs. The FY 2018 ERP report (Ma & al., 2018) also describes the ERP analysis process, ERP analysis tools, and various analysis approaches.…”