Operator action log based monitoring and control and its verification of nuclear power plants

•we proposed a monitoring and controller display method for each operation mode based on log analyses of operator actions.•This method minimizes existing information navigation by providing the means to monitor and control that is necessary for the operator to perform a specific operation mode on one or two display pages. The digital based nuclear plant monitoring system of Korea has problems in that there is a large amount of information to be displayed in a limited display space and the capacity of the operator to process the visual information is also limited. Thus, we propose a monitoring and controller display method for each operation mode based on log analyses of operator actions. This method minimizes the navigation of existing information by providing the means of monitoring and control that is necessary for operators to perform a specific operation mode on one or two display pages. The method provides operators with the monitoring and controller information for each operation mode of an NPP based on an understanding of the work domains. Moreover, through analysis of operation action logs obtained during plant operation, this method complements the monitoring information and the means of control for each operation mode, thus improving the efficiency of the display for each operation mode. This method reduces the time spent searching for information and the transition between display pages. This method has been verified in terms of its function, performance, and operability by prototyping and testing of the prototype, as well as via a consideration of the cyber security and software quality.