Co-simulation is an important tool to capture the complexity of cyber-physical energy systems. The past decade lead us from command-line simulation orchestration to higher readiness-levels in terms of applicability. The configuration and time-domain initialisation of generic co-simulation setups, however, entail a lot of manual activities, especially when simulation components are tightly coupled. This paper provides a qualitative overview on what initialisation challenges crop up and how tools like mosaik can tackle these. This is illustrated with a multi-domain co-simulation example, in which the same time loop concept is applied to resolve cyclic dependencies between simulators during initialisation. The paper provides conclusions about the applicability of same time loops for initialisation purposes and will provide directions for further research on this topic. ... Read more

This chapter provides a brief overview of modelling and simulation approaches for smart grid systems. A special focus is put onto the coupling of simulation environments; i.e., the co-simulation of power systems and its components. Furthermore, selected implementations of standardized interfaces for domain simulators covering the domains of power systems and ICT are presented. ... Read more

This paper presents an approach to extend the capabilities of smart grid laboratories through the concept of Power Hardware-in-The-Loop (PHiL) testing by re-purposing existing grid-forming converters. A simple and cost-effective power interface, paired with a remotely located Digital Real-Time Simulator (DRTS), facilitates Geographically Distributed Power Hardware Loop (GD-PHiL) in a quasi-static operating regime. In this study, a DRTS simulator was interfaced via the public internet with a grid-forming ship-To-shore converter located in a smart-grid testing laboratory, approximately 40 km away from the simulator. A case study based on the IEEE 13-bus distribution network, an on-load-Tap-changer (OLTC) controller and a controllable load in the laboratory demonstrated the feasibility of such a setup. A simple compensation method applicable to this multi-rate setup is proposed and evaluated. Experimental results indicate that this compensation method significantly enhances the voltage response, whereas the conservation of energy at the coupling point still poses a challenge. Findings also show that, due to inherent limitations of the converter s Modbus interface, a separate measurement setup is preferable. This can help achieve higher measurement fidelity, while simultaneously increasing the loop rate of the PHiL setup. ... Read more