Optimisation of Operating Envelope and Safety Margin Using PRA Methods

Abstract

A major challenge in the operation of a nuclear power plant is the maintenance of an acceptable level of risk when equipment performance degrades through component failure or system ageing.The special safety systems play a particularly significant role in this regard. They are routinely tested to demonstrate compliance with availability requirements. The minimum allowable performance capability of systems is derived from safety analysis and other simulations of system performance and response to abnormal events. Overall station performance and risk management can be improved by linking the analyzed operating envelope with the operational performance of systems. The purpose of this paper is to report on investigations of the use of PRA methodology to optimize the operating envelope and safety margins using "live" plant data.