PSA INSIGHTS OF THE NEW NUCLEAR POWER PLANTS

摘要

Four designs of generation III+ pressurized water reactors were analyzed in the framework of the project entitled "Safety characteristics of potential reactors for JEK 2". The project was done at the Reactor Engineering Division of the Jozef Stefan Institute for the Slovenian utility. The analyzed designs selected as potential designs for construction of the second unit at the Krsko Nuclear Power Plant are: Westinghouse AP1000, AREVA EPR, Mitsubishi APWR and ATMEA1 from AREVA and Mitsubishi. The goal of the project was identification and description of the safety characteristics of analyzed reactor designs. The identification of safety characteristics was based on description of the structures, systems, components and their integral performance given in the design documentation of the vendors. The identification was supported by the review of the safety analyses including the Probabilistic Safety Assessment (PSA) organized according to the classifications of the U.S. Nuclear Regulatory Commission. The paper presents results of the review of the PSA section of the Final Safety Analysis Report of the corresponding designs. The obtained results include identification and description of the usage of PSA in design phase for the decrease of the risk measures and elimination of the significant risk contributors. The obtained results for the risk indices, namely the core damage frequency and large release frequency are identified and compared against each other and against requirements of the regulator. The comparison with the currently operating nuclear power plants is done and the major contributors to the decrease of the risk indices are identified.