The Development and Application of Real-Time Risk Monitor System Based on Level 2 PSA for NPP

Abstract

The method of real-time risk monitor system (RM) development based on Level 2 probability safety analysis (PSA) is established and a real-time risk model for a nuclear power plant (NPP) in China is developed in this paper. The risk monitor system can calculate not only the core damage frequency (CDF) but also the large early release frequency (LERF) with different plant configurations. In this paper, the application of risk monitor system will be discussed in two aspects: Configuration risk management and risk-informed technical specification (TS) optimization. Configuration risk management method based on risk monitor system is studied and case analysis is carried out for the NPP, which will improve the plant risk management ability and safety. Risk-informed technical specification optimization approach based on RM is studied and case analysis is performed for the TS, which can prolong the completion time for a single equipment/system failure in TS to improve the operation economy of NPP. In addition, the evaluation of completion time for multiple equipment failures is the supplement to the traditional TS. The Level 2 PSA risk monitor system development is a good engineering practice of Level 2 PSA in NPP, and is of great significance for improving both the safety and economy of the plant.