多机组核电厂总体风险的一级PSA方法研究

福岛核事故发生后，多机组核电厂的总体风险受到越来越多的关注，但国内外缺乏评价多机组核电厂总体风险的方法或导则。本文结合有关法规对核电厂的总体安全要求，探索将单机组的一级概率安全评价（PSA）方法拓展为多机组的风险评价方法。以双机组核电厂为例，讨论了多机组厂址PSA定量化的一些问题，提出了机组间相关性的一些见解，并阐明了数学原理。本文讨论的方法对研究多机组厂址PSA方法具有重要价值。

Study on Level-1 PSA Approach of Integrated Risk of Multi-unit NPP

After the Fukushima nuclear accident, more and more attentions were paid to the integrated risk of multi-unit nuclear power plant (NPP), while there is no any methodology or guideline, at home or abroad on assessing the integrated risk of multi-unit NPP sites. According to the general requirements for NPP sites by relevant regulations, an exploration was developed to assess the integrated risk of the multi-unit site by extending the methodology of level-1 probabilistic safety assessment (PSA) of the single-unit site. A two-unit site was employed as a demonstration to discuss some quantification issues of multi-unit sites, with some insights on dependencies among the units and mathematical mechanisms. The approach discussed in this paper is of important value for the research on PSA methods of multi-unit NPPs.