Evaluation Method of Reliability Indicator of Reactor Protection System

The performance level of reactor protection system is of a great effect on nuclear power plant safety, economy and reliable operation. However, the industry has not formed a consistent methodology on how to correctly evaluate the reliability index of the reactor protection system in practice. In this paper, the applicabilities of fault tree analysis on the probability of failure on demand and Markov method on the malfunction rate were mainly discussed based on a simplified typical reactor protection system. The evaluation methods applicable respectively for the following two indicators, namely the probability of failure on demand and the malfunction rate of the typical system were estimated, and the reliability indicators of the sample system were quantitatively calculated. This research has clarified methodologically problem in the analysis on the reliability evaluations of reactor protection system in China and is of significant value as a reference.