抄録
Probabilistic safety assessment (PSA) is an important tool to evaluate the safety of the nuclear power plant (NPP). As the start of PSA, the quality of initiating events analysis has significant influence on NPP safety assessment and risk informed PSA application. At second generation NPP or primary design stage of third generation NPP PSA in China, the frequency of break initiating events adopted generic data directly which can not reflect design characteristics of NPP completely. Based on the failure mechanism and operating experience, this article carried out analysis on loss of coolant accident（LOCA）, and developed kind of specific piping and non-piping analysis methods which could reflect design characteristics and domestic operating experience, then, calculated the frequency of LOCA. Through comparison with the results of the latest research achievements abroad, the results in this article were proved reasonable. The specific analysis of break initiating events can reflect design characteristics of NPP veritably, and promote the quality of PSA.
