STUDY OF TIME-CRITICAL DIAGNOSTIC METHOD FOR EMERGENCY OPERATION OF NUCLEAR POWER PLANT.

The authors propose a time-critical diagnostic method to secure the safety of the post-accident nuclear power plant, and examine the applicability of both the real-time tracking technique of the plant internal situations using observed singals and the future prediction technique of the important state variables at SBLOCA of PWR plant. In order to back up the operators at the emergency state, the concept of an emergency operation support center is proposed, where the real-time accident tracking simulator and the trend-prediction simulator are installed for the diagnoses. The ability of a real-time accident tracking code, TOKRAC, is examined by the simulations of both TMI-2 accident and 6% coldleg SBLOCA of a Westinghouse-type PWR plant.