Application Of Reliability Analysis Based On Multilevel Flow Models In Nuclear Power Plant

Nuclear power plant is a complex system with complex human-machine interface, complex operation information, complex dynamic characteristics and inferior operation environment. The safe and reliable operation of nuclear power plant is greatly influenced by the prompt and proper operating procedures. In order to reduce the possibilities of human errors, in this thesis the operating procedure evaluation technology for the nuclear power plant based on system reliability analysis is studied and discussed.Firstly, in this thesis, the influences of human errors to the safety of nuclear power plant are summarized, and then, the conceptional design of the emergency operating procedure navigation system is discussed. Secondly, according to the disadvantages of the existing reliability analysis methods, such as Fault Tree Analysis (FTA) and Go methodology, a novel reliability analysis method based on Multilevel Flow Models (MFMRA) is proposed. By using a study case, the differences between MFMRA and Go methodology are also presented. In addition, the Multilevel Flow Models of the primary coolant system, safety shutdown system, safety power cutback system and main steam system, etc are constructed. Finally, the data structures and the algorithms of MFMRA as well as the emergency operating procedure evaluation are also presented and their performances are verified by a simulation case of Steam Generator Tube Rupture (SGTR) accident.This thesis can be a fundamental work for the researches on the reliability analysis based on Multilevel Flow Models, and will be useful to the developments of the emergency operating procedure evaluation system and computerized symptom-oriented emergency operating procedure providing system in the future.