Co-Simulation of a Nuclear Power Plant for Grid Interaction Studies

As a contribution, this paper presents a further development of a previously proposed cosimulation strategy, where thermomechanical and electrical dynamics are simulated using separate domain-specific software in a coordinated manner. The strategy is implemented at a nuclear power plant to demonstrate industrial applicability and enable realistic and practical results based on detailed plant models. A small test model, derived from the plant process, is developed to verify the co-simulation strategy for interaction studies, with a particular focus on the impact of simulation step size. The simulation results show that large step size differences between the coupled software introduce a pronounced time shift, while smaller time steps improve amplitude accuracy. Step size selection is therefore critical and depends on the frequency content of the phenomena under study. The presented co-simulation framework is a tool to be used in the field of interaction studies involving large-scale, multi-domain systems in an evolving power system.