支持系统始发事件建模方法研究

支持系统始发事件（SSIE）是核电厂概率安全分析（PSA）中需考虑的一类特殊始发事件，建模时需要解决的重要技术问题包括:与PSA模型的联接和定量化方式、备用列/设备的任务时间、共因失效、重要度和不确定性分析结果。目前国内各单位在开展PSA工作时对这些问题的处理方式差异很大，可能影响PSA风险见解的合理性。本文结合PSA技术标准要求，通过实例分析和对比，提出以下建议:①SSIE故障树应与PSA整体模型联接并开展定量化分析；②目前2种常见方法——乘数法（Multiplier）和显式法（Explicit）均可使用，但应了解2种方法在重要度分析和不确定性分析中分别存在的局限性并避免造成明显偏差。 

Research of Modeling Methodology for Supporting System Initiating Events

Support system initiating event (SSIE) is a special type of initiating event and should be treated appropriately in the probability safety assessment (PSA). The important technique issues to be addressed in modeling include: PSA modeling linking and quantification methodology, mission time for the standby trains or components, common cause failure (CCF), importance and uncertainty analysis results. The treatments method of these issues was revealed inconsistent for different analyzers and influenced the risk insights of PSA significantly at the present time. Based on the requirements of technical standards, this paper put forward the following suggestions through case analysis and comparison: a. SSIE fault trees should be linked with PSA overall model and quantified; b. Currently two common methods-Multiplier and Explicit are both available. However, the limitations of the two methods in the analysis of importance and uncertainty should be understood, and obvious deviations should be avoided.