Emergency Diesel Generator System Testing Interval Optimization and Uncertain Reliability Parameters Updating

摘要

The object of the considered work was to investigate the possibility to change and optimize the testing intervals of Emergency Diesel Generators System (EDGS) at. Ignalina Nuclear Power Plant (NPP) in such a way, that the safety level of Ignalina NPP would not be decreased. The investigation of EDGS is performed applying the measures related to system reliability. In order to estimate and update the uncertain reliability parameters the Bayesian updating approach is also investigated. As the considered measure and failure data are mainly related to unavailability of EDGS, the system unavailability model is developed and used for the testing interval optimization. The considered approach, models, and received results can be used in the framework of the living probabilistic safety analysis and reliability data updating in order to minimize data uncertainty. The analysis results showed that the interval of testing EDGS at the Ignalina NPP could be increased up to two month. Due to change of testing interval from one month up to two month the average unavailability is changing insignificantly and doesn't exceed the acceptable limit of unavailability.