Session 3B - Digital twins

Title:	The Potential of FMI for the Development of Digital Twins for Large Modular Multi-Domain Systems
Authors:	Marcus Wiens, Tobias Meyer and Philipp Thomas
Abstract:	Digital twins enable the observation, prediction, and optimization of a physical system and thus allow to realize their full potential. However, their functionality is mainly based on simulation models of the entire system behavior. For modular multi-domain systems, this requires the extensive use of dynamically composed models that are made up of individual component models. The FMI-Standard forms a solid foundation for this problem and is very well known in the automotive engineering fields. However, composed system models using FMI are not widely adapted in renewable energy and wind energy yet. So far, the coupling of simulation models is limited. This paper discusses the strategy of building digital twins from individual FMUs with predefined model interfaces based on an ontology for renewable energy systems. An accelerated development is enabled by the exchange of sub-models in the digital twin without adjustments of interface. An example for the proposed process is given by the composed simulation model of a hydrogen generation process based on wind energy.
Keywords:	Digital Twin, Functional Mockup Unit, Wind Energy, Renewable Energy, Ontology
Paper:	full paper
Bibtex:	@InProceedings{modelica.org:Wiens:2021, title = "{The Potential of FMI for the Development of Digital Twins for Large Modular Multi-Domain Systems}", author = {Marcus Wiens and Tobias Meyer and Philipp Thomas}, pages = {235--240}, doi = {10.3384/ecp21181235}, booktitle = {Proceedings of the 14th International Modelica Conference}, location = {Link\"oping, Sweden}, editor = {Martin Sj\"olund and Lena Buffoni and Adrian Pop and Lennart Ochel}, isbn = {978-91-7929-027-6}, issn = {1650-3740}, month = sep, series = {Link\"oping Electronic Conference Proceedings}, number = {181}, publisher = {Modelica Association and Link\"oping University Electronic Press}, year = {2021} }

Title:	Object-Oriented Models of Parallel Manipulators
Authors:	Paolo Campanini and Gianni Ferretti
Abstract:	In this paper, the development of Digital Twins of parallel manipulator is described, based on components of the Modelica standard library only. At first, the dynamic model of a Delta robot is illustrated and validated with respect to experimental data. Then, the model of a Stewart platform is discussed. Thanks to the symbolic manipulation capabilities of the OpenModelica compiler, the model is then used to automatically generate the inverse dynamics, which is in general is a quite difficult task to be performed manually.
Keywords:	Object-oriented modelling, Simulation, Parallel manipulators, Modelica, DAE systems, Closed chains
Paper:	full paper / library
Bibtex:	@InProceedings{modelica.org:Campanini:2021, title = "{Object-Oriented Models of Parallel Manipulators}", author = {Paolo Campanini and Gianni Ferretti}, pages = {241--248}, doi = {10.3384/ecp21181241}, booktitle = {Proceedings of the 14th International Modelica Conference}, location = {Link\"oping, Sweden}, editor = {Martin Sj\"olund and Lena Buffoni and Adrian Pop and Lennart Ochel}, isbn = {978-91-7929-027-6}, issn = {1650-3740}, month = sep, series = {Link\"oping Electronic Conference Proceedings}, number = {181}, publisher = {Modelica Association and Link\"oping University Electronic Press}, year = {2021} }

Title:	A Modelica Library for Modelling of Electrified Powertrain Digital Twins
Authors:	Nikolaos Fotias, Ran Bao, Hui Niu, Michael Tiller, Paul McGahan and Adam Ingleby
Abstract:	In this paper, a Modelica library of electrified powertrain components is presented and its applications discussed. This library is used to construct digital twins of electrified powertrains during product development. These digital twins provide value by reducing time and cost by up to 30% compared to state-of-the-art approaches. Once products are in-service these same digital twins provide value by improving condition monitoring (state-of-health) by up to 10%. The library includes a multi-fidelity and multi-scale battery and power electronics sub-library, an Electrical Drive Unit (EDU) sub-library modelling different types of electrical machines, and an electrified propulsion system sub-library of template models that leverage the battery, power electronics and EDU components found in the other sub-libraries. Finally, an example of applying the proposed library to electrified vehicle development is presented.
Keywords:	Modelica, Digital Twins, Electrified Powertrain
Paper:	full paper
Bibtex:	@InProceedings{modelica.org:Fotias:2021, title = "{A Modelica Library for Modelling of Electrified Powertrain Digital Twins}", author = {Nikolaos Fotias and Ran Bao and Hui Niu and Michael Tiller and Paul McGahan and Adam Ingleby}, pages = {249--261}, doi = {10.3384/ecp21181249}, booktitle = {Proceedings of the 14th International Modelica Conference}, location = {Link\"oping, Sweden}, editor = {Martin Sj\"olund and Lena Buffoni and Adrian Pop and Lennart Ochel}, isbn = {978-91-7929-027-6}, issn = {1650-3740}, month = sep, series = {Link\"oping Electronic Conference Proceedings}, number = {181}, publisher = {Modelica Association and Link\"oping University Electronic Press}, year = {2021} }

Title:	Development of a real-time test bed for indoor climate simulation in a VR environment using a digital twin
Authors:	Kushagra Mathur, Christoph Nytsch-Geusen and Lucas Westermann
Abstract:	This paper describes the development process of a test bed for an interactive VR (virtual reality) environment for indoor climate simulation of buildings. The basic idea is to reproduce the simulated indoor climate of a thermal room model in a climate chamber with the help of air conditioning devices and thus to make the indoor climate directly physically experienceable for a user in real time. In a first step, the real test bed is mapped with the help of a digital twin and simulated in parallel with the room model. In a second step, the digital twin is replaced by the real test bed and the Modelica room model is included then as an embedded model. In this way, the real test bed can be operated with the control algorithm which has been evaluated and optimized in a previous step. The described approach is demonstrated in a case study using a simple single zone building model.
Keywords:	hardware in the loop simulation, digital twin of a test bed, interactive virtual reality environment
Paper:	full paper
Bibtex:	@InProceedings{modelica.org:Mathur:2021, title = "{Development of a real-time test bed for indoor climate simulation in a VR environment using a digital twin}", author = {Kushagra Mathur and Christoph Nytsch-Geusen and Lucas Westermann}, pages = {263--269}, doi = {10.3384/ecp21181263}, booktitle = {Proceedings of the 14th International Modelica Conference}, location = {Link\"oping, Sweden}, editor = {Martin Sj\"olund and Lena Buffoni and Adrian Pop and Lennart Ochel}, isbn = {978-91-7929-027-6}, issn = {1650-3740}, month = sep, series = {Link\"oping Electronic Conference Proceedings}, number = {181}, publisher = {Modelica Association and Link\"oping University Electronic Press}, year = {2021} }

Title:	A first principles thermal losses model of the TCP-100 parabolic trough collector based on the Modelica Standard Library
Authors:	Julia Pérez, Luis J. Yebra, Francisco M. Márquez and Pedro J. Zufiria
Abstract:	The TCP-100 parabolic trough collectors (PTC) research facility at Plataforma Solar de Almeria (CIEMAT) has been specially designed for the development of research activities in Automatic Control of PTC solar thermal power plants. The development of advanced control techniques for this kind of facilities requires dynamic models that should be successfully used in advanced controllers. An important part of these models is the thermal losses submodel, that traditionally has been considered as an experimental steady state correlation. In this paper, a work in progress about a first principles based model of the losses to the environment of a parabolic trough collector is presented, based on the physical phenomena inside any parabolic trough collector during the operation of the TCP-100 solar field. The implementation of the model in the Modelica language has been done prioritizing the use of the Modelica Standard Library classes. Some simulations results of this model with theoretical parameters values under typical operating conditions of the TCP-100 plant are presented, showing higher losses to the environment when compared with the information provided by the TCP-100 manufacturer.
Keywords:	parabolic trough collector, thermal losses, object oriented modelling, Modelica Standard Library
Paper:	full paper
Bibtex:	@InProceedings{modelica.org:Perez:2021, title = "{A first principles thermal losses model of the TCP-100 parabolic trough collector based on the Modelica Standard Library}", author = {Julia P\'erez and Luis J. Yebra and Francisco M. M\'arquez and Pedro J. Zufiria}, pages = {271--276}, doi = {10.3384/ecp21181271}, booktitle = {Proceedings of the 14th International Modelica Conference}, location = {Link\"oping, Sweden}, editor = {Martin Sj\"olund and Lena Buffoni and Adrian Pop and Lennart Ochel}, isbn = {978-91-7929-027-6}, issn = {1650-3740}, month = sep, series = {Link\"oping Electronic Conference Proceedings}, number = {181}, publisher = {Modelica Association and Link\"oping University Electronic Press}, year = {2021} }