There are a variety of different simulation tools to catch the static or dynamic behavior of power systems by running its virtual model on different scenarios. Regarding large‐scale power grid such as national systems, a simulation tool should be able to execute large‐scale models with a lot of new components (e.g. new controllers for DFIGs) and actors in different levels (e.g. MV and LV distributed generations) with interoperability with other infrastructures (e.g. gas network) or layers (e.g. communication layer). High performance computing systems (HPC) as well as Hardware in‐the‐loop setups
is needed to be coupled with the core simulation tool; and execution of models should be controlled in such a way that the dynamic behavior of the real‐world system would be emulated as much as possible.
Moreover, interactions of electricity grids in different voltage levels (i.e. transmission vs. distribution) and different regions with independent control and regulatory systems (e.g. interactions among different DMS‐SCADA together and/or with EMS‐SCADA) imply a multiresolution modelling and simulation of power systems.

Performing “real‐time simulation” seems inevitable to meet all above mentioned simulation requirements:

  • it reproduces the behavior of the real‐world system at the same rate as the wall‐clock time, enabling real‐time human/software/hardware interventions;
  • it provides a distributed parallel computation facility by which different parts of a decoupled large system could be simulated and studied with different input/outputs;
  • it can efficiently regenerate the dynamics of fast events, closed‐loop control and protection actions, and all “what‐if” analysis related to system transients.

Multi‐site real‐time co‐simulation is a cost effective and technically feasible way to connect geographically distributed real‐time simulators via standard communication protocols to mainly improve simulation performance and capability. However, the advantages of such “multi‐site co‐simulation” are beyond enhancing the computation capability through sharing calculation
software and hardware facilities:

  1. Utilization of available software and hardware resources in other laboratories in case they are not available locally;
  2. Soft‐sharing of expertise in a large collaboration consortium for different use cases and studies without physical exchange of researchers and visitors;
  3. Keeping susceptible national data confidential, while running a co‐simulation which integrates such data. As multi‐site co‐simulation mimics real‐world interconnected networks, only boundary data of the interconnection points are shared, and the national or continental system data could be kept confidential.

Test, validation, and/or exploitation of new control algorithms or management strategies without sharing disclosing the models due to IP rights. Experts in a lab where a new algorithm is developed can test and verify it using the co‐simulation platform without sharing it.

Other examples of real-time co-simulations:

Practical implementation of a federation of laboratories located in different European member states, enabling a cost‐effective sharing of hardware and
software facilities with special focus on real‐time simulation.

Example of geographically distributed real‐time
co‐simulation, aimed to conceptually and technically prove feasibility of
multi‐site co‐simulation across the Atlantic Ocean, and demonstrate potential and advantages of a holistic research approach enabled by a “laboratory in a network” through interconnecting EU‐US laboratories.