DEVELOPMENT STRATEGIES OF AN EXPERT SYSTEM FOR MULTIPLE ALARM PROCESSING AND DIAGNOSIS IN NUCLEAR-POWER-PLANTS

This paper describes the development strategies of a prototype expert system, called ESAPD, for multiple alarm processing and diagnosis in nuclear power plants. The main objectives of the system are to assist operators to identify a primary causal alarm among multiple fired alarms and to diagnose the plant malfunction quickly. The overall plant-wide diagnosis is performed at the alarm processing stage which can identify a primary causal alarm and can diagnose possible failure modes and failed systems, and automatic interlock actions. The knowledge base for the alarm processing is represented as object-oriented concepts. The specific root cause diagnosis for the primary causal alarm can be performed at the alarm diagnosis stage. The system can provide operators with the possible causes of the primary causal alarm, emergency actions, and follow-up treatments. The diagnostic method adopted in this system is a ''hypothesize and test'' paradigm.