A method for identifying instrument faults in nuclear power plants possibly leading to wrong situation assessment

In this paper, we propose a method for identifying instrument faults that could potentially affect an operators’ situation assessment capability in nuclear power plants (NPPs), an issue which has received a lot of attention recently. In the proposed method, patterns of selected plant parameter trends in selected plant states and NPP operators’ patterns of selected plant parameter trends in selected plant states are analyzed, and a comparison between the two kinds of patterns is performed to identify instrument faults which could potentially affect a NPP operators’ capability to correctly assess a plant's conditions. An example application is presented to demonstrate how the proposed method can be used to identify the possibilities of operators’ developing a wrong situation assessment because of instrument faults and to identify the corresponding safety concerns. We conclude that in order to get more accurate results, an analysis with a full-scope NPP simulator and interviews with NPP operators will be necessary.