A Simulation Model for the Frequency and Duration of LOOP

Abstract

The Finnish utility TVO has developed a simulation model that allows realistic estimation both of the frequency and of the duration distribution of the Loss Of Offsite Power (LOOP) on a Nuclear Power Plant (NPP). The model is based on the failure rates and recovery time distributions for failures of the components between the station service bus bars of the unit and the external grid. Communication between the control room personnel and the personnel of the grid company, as well as the tasks performed by personnel of the grid company have been modelled. The model has been used in the detailed design of the modifications of the connections from the NPP to the external grid, but also in configuration control of the 400 kV and 110 kV substations close to the NPP. The results have also been used in training all parties participating the maintenance of the grid and recovery of the connections.