Enabling Python Driven Co-Simulation Models with PythonFMU

Abstract

This paper introduces PythonFMU, an easy to use framework for exporting Python 3.x code as cosimulation compatible models compliant with version 2.0 of the Functional Mock-up Interface (FMI). The framework consists of a set of helper classes and a command line utility for transforming compliant python source into ready to use cross-platform FMUs. PythonFMU seamlessly takes care of a number of lowlevel FMI functions such as getting and setting variable values, and state handling, including serialization and deserialization. Furthermore it provides pre-built binaries for Windows and Linux 64-bits, generates the required modelDescription.xml containing meta-data about the model and packages all related files into a Functional Mock-up Unit (FMU) - ready to be imported into any FMI compatible simulation tool. The framework can be effortlessly installed using de-facto standard Python package managers pip and conda. While PythonFMU is more geared towards ease of use and enabling Python driven co-simulation models, it is shown to have adequate performance compared to much more low-level alternatives targeting other programming languages.