Toward an accurate and fast hybrid multi-simulation with the FMI-CS standard

Multi-simulation in the context of future smart electrical grids consists in associating components modeling different physical domains, but also their local or global control. Our DACCOSIM multi-simulation environment is based on the version 2.0 of the FMI-CS (Functional Mock-up Interface for Co-Simulation) standard maintained by the Modelica Association. It has been specifically designed to run large-scale and complex systems on a single PC or a cluster of multicore nodes. But it is quite challenging to accurately simulate FMUs-composed systems involving predictable and unpredictable events while preserving the system overall performance. This paper presents some additions to the FMI-CS standard aiming to improve the accuracy and the performance of distributed multi-simulations involving a mix of both time steps and various kinds of events. The proposed FMI-CS primitives are explained, as well as the Master Algorithm strategies to exploit them efficiently.