Failure analysis of the standby liquid control system for a boiling water reactor with fuzzy cognitive maps

A fuzzy cognitive maps (FCM) application is proposed as a simple method to determine failure modes and effects of the standby liquid control system (SLC) during anticipated transient without scram (ATWS) in a boiling water reactor (BWR). The SLC has an important contribution to the total core damage frequency in a BWR. This is the first step in the development of an expert system that could involve many emergency systems of a BWR to simulate accident sequences, through the knowledge representation and reasoning with FCM designs in order to automate the decision making process. A simplified model of the SLC is analyzed with the fault tree analysis technique in order to compare this results with those obtained with the FCM and show consistency with the results, in order to see that both techniques show similar results even if the approaches are different.

► FCMs are proposed in order to determine failure modes in systems and equipment in BWRs.
► A simplified model is compared with the fault tree analysis technique.
► Five case scenarios are studied in order to test the performance of the method.
► The proposed method shows consistency with the traditional fault tree technique.