Overview

The Functional Mock-up Interface (FMI) is a free standard for exchanging or coupling simulation models created with different simulation tools. This is often the case when the models are provided by different suppliers or domain-specific simulation tools are used to simulate the different aspects of a machine or plant (e.g. thermal simulation, control engineering simulation).

A simulation tool that supports FMI allows a model to be exported or imported as a Functional Mock-up Unit (FMU). This can be done as a model exchange or co-simulation. In the case of the former, the pure simulation model is exported. In the latter case, the associated solvers are also exported, so that the calculations of the model in the "target simulation tool" happen analogously to the initial tool.

When exporting an FMU, some simulation tools offer the choice of encapsulating the behavior of the model in a DLL or / and exporting the behavior of the model as source code. The latter option is mandatory for an FMU to be imported into TwinCAT. Thus, only FMUs whose behavior is available in the FMU as source code can be imported.