Expert system for refueling procedure planning

A station nuclear engineer plans the refueling procedure in preparation for a refueling outage. The refueling procedure consists of a series of fuel movements, such as loading, discharge and relocation to complete the core configuration for the next cycle. The engineer must take into account various constraints on the procedure, and must minimize the total number of fuel movements in the procedure, because the refueling process is in the critical path of the overall outage. We have developed an expert system for refueling planning. The system was applied to the refueling outage of Onagawa-1 (524 MWe BWR) and proved to be effective; the required planning time was reduced from 10 days to 30 minutes, and the number of fuel movements reduced. (author)