核电厂自适应采样下风险指引的安全评价与优化方法研究  

Study on Risk-informed Safety Evaluation and Optimization under Adaptive Sampling in Nuclear Power Plant

作　　者：李林峰 徐安琪 董晓朦 张桢 杨明 文婷 刘永 Li Linfeng;Xu Anqi;Dong Xiaomeng;Zhang Zhen;Yang Ming;Wen Ting;Liu Yong(Shenzhen Key Laboratory of Nuclear and Radiation Safety,Shenzhen University,Shenzhen,Guangdong,518060,China)

机构地区：[1]深圳市核与辐射安全重点实验室,深圳大学,广东深圳518060

出　　处：《核动力工程》2024年第S2期223-230,共8页Nuclear Power Engineering

基　　金：国家自然科学基金青年科学基金(12405214);广东省基础与应用基础研究基金(2022A1515110420);深圳市优秀科技创新人才项目(RCBS 20221008093227028);中核集团青年英才菁英项目。

摘　　要：为了满足先进反应堆安全性与经济性双重需求,本文将确定论安全分析与概率安全分析相耦合,以“风险指引的系统分析(RISA)”为基础,重点突破高精度要求下的抽样次数海量、计算效率低的难题,提出了一种自适应采样策略下的RISA优化方法,现实评估核电厂安全裕度。采用支持向量机(SVM)、K近邻(KNN)算法训练得到代理模型,替代大量的最佳估算加不确定性分析程序模拟;并且用自适应采样策略识别极限面,降低抽样范围和次数。以小破口失水事故(SBLOCA)为例进行测试验证,结果表明:相比于随机抽样RISA结果,代理模型预测的燃料包壳峰值温度(PCT)结果接近、计算时间减少50%以上。本方法可支撑RISA实际工程应用,为风险指引的设计、运行与管理提供现实精准的决策支持。In order to meet the dual requirements of safety and economy of advanced reactors,the Deterministic Safety Analysis and Probabilistic Safety Analysis are coupled in this study.Based on the Risk-informed System Analysis(RISA),a RISA optimization method under adaptive sampling strategy is proposed to realistically evaluate the safety margin of nuclear power plants.It focuses on solving the problems of massive sampling times and low calculation efficiency under high precision requirements.Support Vector Machine(SVM)and K-Nearest Neighbor(KNN)Algorithm are used to train the surrogate model,which replaces a large number of Best Estimation and Uncertainty Analysis code simulations.The adaptive sampling strategy is used to identify the limit surface and reduce the sampling range and times.Taking the Small Break Loss of Coolant Accident(SBLOCA)as an example,the test results show that,compared with the random sampling RISA results,the peak temperature of fuel cladding predicted by the surrogate model is close,and the calculation time is reduced by more than 50%.Therefore,this method can support the practical engineering application of RISA in the future,and provide realistic and accurate decision support for the risk-informed design,operation and management.

关 键 词：核安全分析 自适应采样 代理模型 风险指引的系统分析(RISA) 风险指引的安全裕度特性分析(RISMC) 

分 类 号：TL364[核科学技术—核技术及应用]