Transnational Federated Testbed: Analyzing Impact of Network Parameters on T&D Co-Simulation

The penetration of distributed energy resources (DERs) into the power system increases the size requirement of the models to induce actual system characteristics, since the simplification of sections of the model as lump load or source may result into misleading conclusions during dynamic and transient conditions. Growing interest on studying of DERs connected grids is enormously risen to investigate present and future systematic issues in dealing with natural and forced outages. This causes a new resource problem for smaller research organizations, utilities and vendors as more expensive, real-time simulators must be purchased to sufficiently simulate large enough models. However, researchers have built communication tools that allow labs to pool their resources by connecting their individual real-time simulators, emulators, and real DER assets together through the internet, allowing them to co-simulate larger/more detailed models that were previously too large for their individual labs. There is a limited focus on the impact of communication delays on federated co-simulation test beds. The main contribution of this work is to analyze the effect of the data rate and latent communication that are used to connect the two labs during the co-simulated transient events. The results are verified by running a co-simulated event on RTDS at Washington State University (WSU) in Pullman, Washington, and the Indian Institute of Technology Kanpur(IITK) in Kanpur, India, by comparing the simulated measurements of the connection between the transmission and distribution systems in both simulations and finding the error between those sets of measurements. Further, it investigates different faults on the distribution system and provides the optimal data rate to achieve the best accuracy of dynamic simulations running at dispersed locations.