Study on Quantitatively Evaluate Situation Assessment Reliability in Digital NPPs Based on Fuzzy Logic Approach

Situation awareness (SA) is a crucial factor impacting operators’ decision-making and performance in nuclear power plants (NPPs). Situation assessment reliability results can be used to support human reliability analysis. To evaluate situation assessment reliability, first, it needs to determine the main influencing factors of SA, and the SA model is constructed based on the factor analysis result of influencing factors. Second, the membership degree of influencing factors under different fuzzy set levels is calculated based on the fuzzy membership function and the probability distribution of intermediate variables are determined on the basis of the constructed SA model, and a quantitative evaluation method of situation assessment reliability is established. Final, a case is used to illustrate the application of the quantitative assessment method of situation assessment reliability. The results show that the proposed quantitative evaluation approach of situation assessment reliability can provide accurate data. These results can provide support for human reliability analysis in digital NPPs.