Modelica conference special issue

Modelica Association Newsletter, issued on 15 September 2023

Modelica Conference logo

Table of contents

Letter from the Board

Dear Modelica, FMI, SSP, DCP, eFMI interested,

The International Modelica Conference 2023 will take place Mo. Oct. 9 - Wed. Oct. 11, 2023, in Aachen, Germany, as a face-to-face conference.

This Newsletter is a special edition for this conference. You get here an overview of the most important topics. More details are given in the articles and on the conference web page.

Scientific papers available

The scientific papers of the conference are already available for everyone: Clicking on sessions and then on a particular session, will show the abstracts together with the pdf-documents of the session papers. Scientific papers are presented on Tue. Oct. 10 and Wed. Oct. 11.

Two keynotes

There are keynotes about Dealing with complex models and how to use the idealization of physics to our advantage from Dr. Dirk Zimmer (DLR-SR) on Tue. and about Relevance of Dynamic Simulation of complex systems in Building Technology - review and outlook from Dr. Bruno Lüdemann (ROM Technik) on Wed.

8 Tutorials

On Mo., Oct. 9, 13:30 - 16:30, there are eight, free tutorials for various topics. Click on sessions, select Monday and then the respective tutorial. This shows an abstract and pre-requisits for the tutorial (e.g. software that you should download before the tutorial, and/or expected knowledge). Please, mark during registration the tutorial that you plan to visit to help with the organization of the tutorial (if you already registered, you will get soon an email how to provide this information).
More information to some tutorials are given in the articles below.

Vendor presentations

On Mo., Oct. 9, 17:00 - 19:15, there are various vendor presentations. Click on sessions, select Monday and then the respective vendor session. This shows the vendor and an abstract. More information to some vendor presentations are given in the articles below.


There is a permanent exhibition during the conference. You can see the list of the exhibitors in the left column of the Conference web page. Exhibitor LTX is also the backoffice of the Modelica Association (MA) and will provide MA material.

FMI user meeting

On Tue., Oct 10, 13:45 - 15:00, there is an FMI User Meeting.

Modelica Association meeting

The day after the conference, on Thur. Oct. 12, there are various meetings from the Modelica Association and other organizations at RWTH Aachen, close to the conference location. An initial schedule is given on the Conference web page. The meetings are open to guests and provide an opportunity to get in contact with the Modelica Association and associated projects and publicly discuss ideas, feedback, requirements and new use cases. If you plan to participate please write to the provided email addresses to help with the organization.

I hope to see you at the conference and especially at the welcome reception on Mo. Oct. 9, 19:15 - 21:00.

Martin Otter on Sept. 14, 2023

Chairperson of the Modelica Association

This article was provided by Martin Otter Modelica

Invitation from local organizers

Conference Logo

We, the local organizers of this year’s Modelica conference are looking forward welcoming you in Aachen. We managed to book Das Liebig as conference venue, a former industrial building, which was recently renovated and is now one of the most modern conference sites in Aachen. With valuable input by the Modelica community, we did compile a diverse Conference Program, which includes interactive Tutorials, Vendor Presentations, as well as scientific posters and sessions.

We are a total of three instutes organizing this conference.

Institute for Energy Efficient Buildings and Indoor Climate

With more than sixty scientists, employees in technology and administration, and other student workers, the Institute for Energy Efficient Buildings and Indoor Climate has its research focus on the reduction of energy demand to create thermally comfortable interiors.

In addition to the main consideration of buildings, vehicle interiors are also investigated. The coupling of measures on the building exterior and system technology to increase the energy efficiency of buildings lies within the context of energetic district approaches with the linkage of thermal and electrical networks. For the development of decentralized energy supply concepts with integration of renewable energy sources, concepts of generation-, load-, and storage-management with intelligent communication between all components are devised. The work of the institute is based on comprehensive test equipment and advanced simulation methods, as well as the coupling of simulation and real hardware using hardware-in-the-loop and FMI. The institute developed and maintains the open-source Modelica libraries AixLib and BESMod, and uses Modelica as the central simulation method.

Institute for Automation of Complex Power Systems

The goal of ACS is to implement a multidisciplinary research approach able to capture the most recent advances in ICT to support the solution of the most advanced problems in the area of grid dynamics and automation.

In order to achieve this vision the research in ACS is organized around three main pillars:

  • Grid operations
  • ICT for Energy
  • Control and Automation Thanks to a multidisciplinary team that works at the intersection of traditional power systems with advanced control and automation concepts and modern ICT solutions, the research at ACS can cover, in a unique way, the following scientific areas:
  • Joint analysis and design of power grid and communication infrastructure in future grids
  • Modern control architectures and protection techniques
  • Electrical distribution and usage in home, neighborhood and urban energy systems
  • Distributed measurements and monitoring
  • Data driven solutions for energy systems
  • Future Internet for energy systems
  • Advanced computing for simulation applications
  • Real time simulation and Hardware-in-the-Loop testing
  • System software and computer architectures for parallel co-simulation of power and communication systems

ACS constantly develops and expands an advanced testing facility, a research topic in itself, installed in the ACS laboratory with unique custom solutions for

  • real-time simulation of power grids,
  • hardware in the loop testing,
  • power hardware in the loop testing,
  • mixed power, control and communication simulation.

Institute of Energy and Climate Research (IEK) - Energy Systems Engineering (IEK-10)

IEK-10 develops models and algorithms for the simulation, optimization and control of energy systems, which are characterized by a high spatial and temporal variability of energy supply and demand, an increasing degree of intersectoral dependencies as well as an increasing digitalization. The focus is on multi-physical energy grids, industrial energy systems, and buildings and districts. A major goal of the research is to provide scalable and faster-than-real-time capable methods and tools that enable energy-optimal, cost-efficient and safe design and operation of these future energy systems. For this purpose, physical-technical system descriptions are combined with machine learning methods and customized simulation and optimization methods are developed especially for multicore, cluster and high-performance computers, which enable the handling of large-scale problems. With the help of the Reallabor “Living Lab Energy Campus” as well as a “Hardware-in-the-loop” laboratory, these innovative solution approaches for future energy systems are tested and validated under almost realistic conditions.

This article is provided by Fabian Wuellhorst and Dominik Hering (RWTH Aachen

Conferences and user meetings

eFMI® Tutorial

eFMI® Tutorial

Time: Monday, 09/Oct/2023, 1:30pm–4:30pm (including 30min coffee break)

We are happy to announce that there will be an extensive tutorial on current eFMI® tooling at the conference. The tutorial will demonstrate the current state-of-the-art of available eFMI tooling. Participants will get a very high-level overview of the eFMI worklflow and a hands-on experience of it for selected Modelica example models. They will configure a tooling workflow from acausal physics models in Modelica down to embedded target code and have a chance to investigate the generated eFMUs and their various intermediate model representations. Besides setting up and experiencing the eFMI workflow, we will also focus on the non-functional quality criteria satisfied by the generated solutions, like traceability within eFMUs, MISRA C:2012 conformance of generated production code and other code quality criteria like static memory allocation and error handling.

Requirements: To conduct the tutorial, participants have to bring their own computer with Windows 10 or 11, 64-Bit, x86. All required software – except operating system – will be provided to participants via a password protected download, available two days ahead; please write an e-mail to (MAP eFMI project leader) that you like to participate to get timely access. It would be very kind when you download the provided software ahead of time to reduce your preparation time and risk of technical issues at the tutorial. Thank you!

If you have any general questions regarding the tutorial, you can contact our public mailing list, (no Google account required).

This article is provided by Christoff Bürger (Dassault Systèmes)

MAP eFMI® Forum

Time: Thursday, 12/Oct/2023, 9:30am–12:00am (noon).

We are happy to announce that there will be an open discussion panel providing an opportunity to get in contact with MAP eFMI® and publicly discuss ideas, feedback, requirements and new use cases; or simply clarify any questions you have about eFMI. The forum is an unique chance to get in contact with eFMI experienced tool developers and users and more deeply discuss any ideas you got from the tutorial on Monday.

If you are interested to join, please write an e-mail to:

  • (public mailing list; no Google account required)
  • (private e-mail address of MAP eFMI project leader, if you do not want your mail in public space)

This article is provided by Christoff Bürger (Dassault Systèmes)

IBPSA Modelica Working Group

IBPSA Modelica Group Logo

The IBPSA Modelica Working Group will held its first expert meeting on October 12, 2023, at RWTH Aachen. At the Expert Meeting, the development of the IBPSA Modelica Library will be coordinated. The Modelica IBPSA Library is a free open-source library with around 1000 models that are used as the core of the Modelica AixLib, Buildings, BuildingSystems and IDEAS libraries.

For the agenda, visit our Github wiki.

Registration is open until 30th of September via the conference web site.

Who should attend?

Attendees are expected to have contributed to the IBPSA Modelica Working Group, or plan to make contributions to the group. These expert meetings are used to coordinate the work. Therefore, participation by people who work on the IBPSA Modelica Working Group is important.

If you are interested in learning more about the Modelica IBPSA Library, consider attending the Modelica IBPSA Tutorial.

This article is provided by Michael Wetter (Berkeley Lab)

Modelica IBPSA Tutorial

IBPSA Modelica Image

This workshop will teach fundamentals for HVAC and control modeling using the Modelica IBPSA Library and OpenModelica’s OMEdit environment.

In this workshop, developers of the AixLib, Buildings, BuildingSystems and IDEAS Libraries and of the OpenModelica environment will give an introduction to OMEdit and present best practices for modeling HVAC and control systems with Modelica. The workshop is targeted to new users. Participants will conduct hands-on exercises using OMEdit and the Modelica IBPSA Library. The workshop will close with an overview of the four libraries that use the Modelica IBPSA Library as their core.

About the Modelica IBPSA Library

The Modelica IBPSA Library is a free open-source library that is used as the core of the Modelica AixLib, Buildings, BuildingSystems and IDEAS libraries. The Modelica IBPSA Library has been developed over the past decade, from 2012-17 as part of IEA EBC Annex 60, from 2017-22 as part of IBPSA Project 1 and since 2022 as part of the IBPSA Modelica Working Group.

Agenda and Registration

For workshop agenda, visit our github wiki.

Registration for the workshop is done through the conference registration.

This article is provided by Michael Wetter (Berkeley Lab)

FMI at the Modelica Conference


FMI is one of the hot topics at the coming Modelica Conference!

FMI Beginners’ Tutorial

There will an FMI beginners’ tutorial on Oct 9 presented by the FMI project on the first day of the conference. You can find more information here, where also the material and installation instructions will be provided.

Talk on Layerd Standards to FMI

Members of the FMI project will present the concept of layered standards to the FMI standard.

The FMI standard - just like any other standard - faces the challenge of balancing generality with enabling specific use cases. Including every domain or use case specific extension in the core standard would significantly increase its length, making it difficult to read and implement. To allow for extensions of the core standard for specific use cases, the Modelica Association adopted the concept of layered standards, first in the SSP standard and later in FMI.

Layered standards to the FMI Standard can be defined by any organization, not just the FMI project. The FMI project is currently working on the following layered standards.

  • FMI-LS-XCP - XCP support of FMUs
  • FMI-LS-BUS - simulation of network communication with FMI
  • FMI-LS-STRUCT - representation of regular maps with FMI 3.0 arrays and the structuring of parameters

FMI User Meeting

The FMI user meeting will take place on Oct 10 as a separate session. The FMI Project and other related Modelica Association Projects SSP and eFMI will present their status and outlook. Additionally there will be two “industrial user presentations” and a Q&A.

FMI Design Meeting on Oct 12th open to the public (on the day after the conference)

If you are interested in a deeper exchange with the FMI project you are welcomce to join the FMI design meeting on Oct 12 (the day after the conference) as a guest. The meeting is scheduled 9:30 - 12:30 h, optionally discussions can continue after lunch until 15:00 h. There you can get in touch with the FMI Project members, discuss ideas, provide feedback, requirements, and new use cases for the FMI. If you plan to participate please write to

This article is provided by MAP FMI

Vendor news


Modelon is proud to be a silver sponsor of the upcoming International Modelica Conference. This year’s conference is an in-person event taking place in Aachen, Germany on October 9-11, 2023. The Modelica Conference brings together users, library developers, tool vendors, and language designers to discuss the latest findings and trends related to the family of Modelica standards. As contributions to the conference program, Modelon will host a tutorial session, a vendor presentation, present a couple of papers, and be available for your questions and to talk shop at our booth. And last but not least: we are hiring! Looking for a job? Come talk to us at our booth!

Tutorial Session: Techno-economical assessment of industrial infrastructure – optimal design and control to reach net-zero

Dynamic optimization based on CasADi has been around for a number of years and the advantages of this dynamic trajectory-based optimization approach are well understood. However, it has always been quite inaccessible and hard to integrate into engineering design workflows. With Modelon Impact, we are introducing a fully integrated solution to enable this exciting and powerful technology.
In this tutorial, we will showcase advanced workflows of Modelon Impact – Modelon’s cloud-based system simulation platform and enables the linking of Modelica with CasADi. Modelon Impact is an easy-to-use tool that provides the ability to not only find the optimal design of your system infrastructure but also deliver the optimal control of the individual components for minimal carbon emissions and cost. Participants will only require a laptop that has either Google Chrome or Microsoft Edge built on Chromium.

Vendor Session: Meet Modelon Impact – a cloud platform for virtually designing, simulating, and analyzing industrial systems.

What happens when you combine the power of cloud technology with powerful system modeling and simulation? The emergence of cutting-edge MBSE application possibilities for commercial utilization. In this session, we’ll walk through real-world examples of how Modelon Impact goes beyond the traditional use of Modelica-based system simulation tools. We’ll also discuss the most recent updates to Modelon’s Modelica libraries, Modelon Impact, as well as what users can expect from the platform and its libraries in the near future.

Paper presentations by authors from Modelon:

Session: Automotive Applications 1,

Time: 11/Oct/2023: 2:00pm-3:15pm · Location: Charles Mass Conservation in Vapor Compression Cycles: A Method for Ensuring Consistency with Redundant Dynamic States Daniel Andersson2, John Batteh1, Matthis Thorade3, Lixiang Li1

Session: Industrial User Presentations,

Tuesday, 10/Oct/2023: 3:30pm - 5:10pm Linking Design Requirements to FMUs to create LOTAR compliant mBSE models Clément Coïc1, Mark Williams2, Juan Carlos Mendo3, Jose Maria Alvarez-Rodriguez4, Marcus Karel Richardson3

Session: Poster Presentations

Time: 10/Oct/2023: 3:00pm-3:30pm · Location: Room Gold Calibration Workflow for Mechanical and Thermal Applications Tim Willert1, Peter Sundström2

To register for this conference, please visit the International Modelica Conference website

This article is provided by Swati Tyagi (Modelon)


At the International Modelica Conference 2023, JuliaHub will be discussing their next-generation modeling and simulation platform, JuliaSim. Vice President of Modeling and Simulation, Chris Rackauckas, and Senior Director of Product Management for JuliaSim, Michael Tiller, will be on hand to discuss the latest features in our new JuliaSim tool as well as the platform it is built on, JuliaHub.

In particular, we’ll be discussing ModelingToolkit, an open source Julia package for building high-performance symbolic-numeric equation based models. We will also be discussing our new HVAC and Battery libraries built on top of ModelingToolkit which will be available in our forthcoming web-based modeling environment, JuliaSim. Finally, we’ll be discussing how our new Digital Echo methdology allows customers to transform their existing, physics-based models (including FMUs) into surrogate models which are accurate to within a few percentage points but run significantly faster. The performance of these tools is described in the following paper which shows how an HVAC model, running in the JuliaSim environment and leveraging our Digital Echo surrogate technology, demonstrated a 590x speed-up over previous models.

We will be happy to answer questions about these technologies or any of our other technologies like our model calibration and optimization tools or our control system design and analysis capabilities. We are looking forward to seeing you all at the International Modelica Conference 2023, in Aachen.

JuliaSim Architecture

This article is provided by Michael Tiller (JuliaHub)

Maplesoft’s MapleSim 2023

MapleSim image

Visit the vendor presentation from our conference sponsor Maplesoft to hear how the Modelica-based commercial tool MapleSim has been updated for 2023 with new capabilities to support system-level modeling and simulation alongside powerful analytic capabilities.

MapleSim provides engineers with an easy to use tool for design exploration and simulation, and offer options to connect the model to other product development tools across an existing toolchain. This session will be an overview of some of the unique features of MapleSim, as well as an update on the latest software enhancements.

This article is provided by Thomas Richard Maplesoft

XRG Contributions to the International Modelica Conference 2023

XRG Logo

On the Modelica Conference 2023 XRG will be present with a booth, informative vendor session and three scientific talks about machine learning, zero-mass flow analysis and complex energy system modelling. If you haven’t registered yet: Do it now!

Our Booth

Annika Kuhlmann and Stefan Wischhusen are looking forward to meeting you at our booth in the exhibition area. Sneak around for an eye-2-eye conversation at any time.

Our Vendor Presentation: Welcome to the world of XRG!

In this presentation given in Room Silver, we will introduce you to our latest advancements and special features in Modelica libraries and tools, showcasing the extremely enhanced capabilities of our HumanComfort Library, HVAC Library, ClaRaPlus Library and our very efficient Score Excel AddIn enabling simulations for everyone.

Discover how these multi simulation platform solutions empower you to efficiently simulate and model diverse scenarios, optimize thermal behavior, analyze HVAC systems, simulate power plants, and remotely control FMUs or Dymola from the familiar Excel interface.

Our Talks

Not less than 3 XRG talks have made it to the program:

  • Julius Aka et al.:“Efficient Global Multi Parameter Calibration for Complex System Models Using Machine-Learning Surrogates”, Room Oxygen, Tue. 10:35 AM (Link to seesion and to Paper)
  • Robert Flesch et al.:“Understanding and Improving Model Performance at Small Mass Flow Rates in Fluid System Models”, Room Silver, Tue. 01:45 PM (Link to seesion and to Paper)
  • Ales Vojacek, Johannes Brunnemann et al.:“Status of the ClaRa Library: Detailed Transient Simulation of Complex Energy Systems”, Room Silver, Wed. 02:00 PM (Link to seesion and to Paper

The colleagues will be happy to answer your questions during the discussion.

This article is provided by Stefan Wischhusen XRG Simulation GmbH

TLK Energy at the Modelica Conference 2023

TLK Energy Logo

This year TLK Energy GmbH is Silver Sponsor of the Modelica Conference in Aachen.
Yann Pellny will give a presentation on “Balance of Plant Simulation for Electrolyzers”. He will present TLK’s work in collaboration with Neuman & Esser on the highly topical issue of hydrogen production. In general, the efficiency and power density of Proton Exchange Membrane (PEM) electrolyzers depend on several factors, such as the membrane itself, the liquid distribution, its design and the resulting heat and mass transfer.

To ensure safe and efficient operation under transient conditions, various parameters such as stack temperature and membrane moisture must be controlled. This is referred to as “Balance of Plant”. Here, simulation offers an excellent tool to analyze the overall system and find the right control strategy.

Yann will present a simulation model, that uses two simulation libraries:

  1. PSL - Process Systems Library
  2. TIL Suite with the Add-On Hydrogen Systems

When? October 10, 2023, approx. 3:45pm - 4:15pm
Where? Room Carbon

Visit us at the conference for a face-to-face meeting. We look forward to discussing your use cases and demonstrating our tools.

This article is provided by Lina Rosenthal (TLK Energy GmbH)

Upcoming: System Modeler 14

Visit our booth and vendor session at the Modelica conference to get a peak preview of System Modeler 14

Alt text

The upcoming version will come with features that will accelerate your model development workflows. Some of the key features are:

  • Analyze Models using Uncertainties: Attach uncertainties to parameters, initial values or inputs and observe their effect on the system.
  • Automatic Unit Validation & Inference: Create robust and user-friendly models, with validation of unit consistency and automatic inference of units through equations and connections.
  • Distribute Libraries: Ensure smooth installation of your libraries including handling of licenses, assets and dependencies.

This article is provided by Ankit Naik Wolfram


Attend vendor session at the Modelica conference to learn about the next-generation scientific computing and system modeling simulation platform MWORKS

After 15 years of development, MWORKS has evolved from a simple Modelica modeling and simulation environment into a next-generation scientific computing and system modeling simulation platform. Based on Modelica, MWORKS.Sysplorer offers a multi-paradigm integrated modeling and simulation environment including physical modeling, block diagram modeling, and state machines. Built on Julia, MWORKS.Syslab provides an integrated scientific computing development environment. Syslab seamlessly integrates with Sysplorer. Additionally, MWORKS offers cloud versions of Sysplorer and Syslab, known as MoHub.

This article is provided by Fanli ZhouSuzhou Tongyuan Software & Control Technology Co., Ltd.

LTX at the Modelica Conference 2023

LTX Logo

LTX is sponsoring the conference in Aachen as a platinum sponsor. The main motivation is to give back some of the funds we charge for operating Modelica Association Backoffice.

We are looking forward to talk to you at our booth, if you are are interested in

If you would like to arrange a personal meeting, please contact

This article is provided by Leo Gall (LTX Simulation GmbH)

Dassault Systèmes Vendor Session

You will discover the latest news and perspectives regarding Dymola and underlying technologies, as well as the portfolio of libraries. Also included: latest standards support and examples of workflows involving native and web clients of the Dassault Systèmes offer.

This article is provided by Dag Brück