2025-09-09 –, Audi-Midi
This paper presents the CDL-PLC translator, a tool to convert control sequences for building heating, ventilation, and air conditioning (HVAC) systems expressed in a subset of Modelica called Control Description Language (CDL) which is undergoing standardization via the voluntary ASHRAE Standard 231P into the IEC 61131-10 XML format. Such a translation is a step in a model-based design workflow and contributes to digitalizing the control delivery process in the building sector. The translation into the IEC 61131-10 XML is the last step in the implementation of control logic developed in CDL on programmable logic controllers (PLCs) standardized in IEC 61131. The paper presents the details of the translator, an example for the validation of a CDL block vs. the corresponding IEC block, and a practical application example for the translation of a control sequence for a hybrid heat pump plant from a case study neighborhood in Belgium. Practical applications, use cases, and future developments are discussed in the context of building industry processes.
Michael Wetter is a Senior Scientist at the Lawrence Berkeley National Laboratory.
His research includes integrating building performance simulation tools into the research process, as well as their use for design and operation. He is leading the development of the Modelica Buildings Library, of OpenBuildingControl, and of Platform Based Design for energy systems.
He was the co-operating agent of IBPSA Project 1 and of IEA EBC Annex 60 and he now leads the IBPSA Modelica Working Group, three multi-national projects that led to the Modelica IBPSA Library that is now used as the core of the Buildings, the AixLib, the IDEAS, and the BuildingSystems libraries.
He is a recipient of the bi-annual Outstanding Young Contributor Award of IBPSA, and of the bi-annual Distinguished Achievements in Building Simulation Award of IBPSA-USA. He is the Chair of the College of Fellows of IBPSA, an IBPSA Fellow, and a member of the Board of the Modelica North America Users’ Group. He was Treasurer of IBPSA and President of IBPSA-USA.
Karl Walther’s research focuses on control of building and district energy systems, model-based building and HVAC design in Building Performance Simulation, and digitalized design-build-operate workflows. He holds a PhD from the University of Wuppertal, Germany, and is currently a postdoctoral researcher in the Thermal Systems Simulation team at KU Leuven, Belgium.
