A diagnostic expert system for analyzing multiple-failure transients in nuclear power plants

CATALISP (Computer Aided Transient Analysis coded in Lisp) is a prototype expert system which is the result of a project investigating and implementing event confidence-levels (used by reactor safety experts in reactor transient analysis) in the form of an expert system. Currently, CATALISP is designed to diagnose reactor transients by analyzing simulated sensor and plant thermal hydraulic information from a system simulation. CATALISP uses a knowledge base of existing emergency nuclear plant operating guidelines and detailed thermal-hydraulic calculation results correlated to confidence-levels. CATALISP can diagnose a number of reactor transients (for example, loss-of-coolant accidents, steam-generator-tube ruptures, loss-of-offsite power, etc.). Future work includes the expansion of the knowledge base and improvement of the “deep-knowledge” qualitative models.