Hardware in the Loop Tests for thermal systems
Testing on test benches take up a lot of resources, are tedious and expensive. We enable tests with virtual prototypes of heat pumps, refrigerators or energy technology plants. This increases your test coverage, improves the quality of your control software and avoids errors in the field.
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Test bench vs. hardware-in-the-loop testing
Modelling thermal systems such as refrigeration cycles in heat pumps is complex. This is why control systems are often tested as they were 40 years ago: in elaborate experiments on test benches in the laboratory.
In contrast, hardware-in-the-loop (HiL) tests have long been established in the development of controllers for mechanical and electronic systems. Here, the controlled system is mapped virtually as a simulation model. In this way, the control unit can be tested in a closed control loop, even without a real prototype of the plant.
Tests on the test bench
Test benches always fully booked
Time pressure
Is everything really tested?
Long iteration loops
Limited reproducibility
Software problems only discovered by the customer
Risk of callbacks due to increasingly complex functions
Another compressor destroyed...
Hardware-in-the-loop tests
Parallel development of hardware and software
100% test coverage
Perfect reproducibility
Protection during software updates
Fewer complaints
Automation
Shorter development cycles
Closed loop tests from the beginning
Would you like to see if HiL is a good fit for your system?
Book an initial meetingYOUR ADVANTAGES WITH HIL
Test better, increase quality, develop faster
Easy testing even under extreme conditions
Faults often occur under extreme conditions. On the test bench in the laboratory, extreme conditions are associated with a great deal of effort.
In hardware-in-the-loop tests, extreme conditions can be simulated very easily. No matter whether 20 °C or -60 °C. That way you can find errors already during tests and not only in the field.
Test at any time, even without a test bench
Via HiL, you can test the current software status in a closed control loop at any time. Also automated over night.
Image source: speedgoat.com
Regression tests possible with software updates
Measurements on the test bench always contain uncertainties. Tests with simulation models are 100 % reproducible. This means that errors can be avoided in future software updates through regression tests.
Increase quality of control software, reduce complaint rate
HiL tests with a virtual prototype enable early and systematic testing. This allows you to detect problems and errors early in the development process. Not just on the test bench in the laboratory or in the field at the customer.
Reach the market faster
With the simulation models as virtual prototypes, control algorithms can be tested from the first idea to the final version, allowing software and engineering teams to work in parallel. This saves time and enables shorter development cycles.
References
Heat pump modeling for HiL tests
In their development process of heat pump controllers Vaillant has established a comprehensive testing strategy. Before they connect developed controllers to real heat pumps in their lab, they are connected to virtual heat pumps running on special real time simulation hardware and software from dSPACE. Crucial ingredients for this so-called Hardware-in-the-Loop (HiL) tests are simulation models of the heat pumps, that are accurate, fast and robust. We developed these models for Vaillant using our Modelica library TIL Suite and set up a reliable tool chain to export these models to dSPACE platform. The models include a full dynamic physical model of the refrigeration cycle. It can handle switching of refrigerant flow direction caused by different modes for defrost, heating and cooling. Vaillant is now able to detect issues in control code much earlier and saves with this virtual testing a considerable amount of expensive lab experiments.
Manuel Gräber et al.: Physical Modeling of Heat Pumps for Hardware-in-the-Loop Testing. 13th International Modelica Conference, 2019
HiL testing for flexible chemical processes
In the HyControl research project, TLK Energy develops dynamic simulation models for process engineering plants that can be used in Hardware-in-the-Loop (HiL) tests. The models represent, among other things, electrolyzers and downstream processes such as methanol synthesis and are optimized for real-time operation.
For HiL testing, the virtual plant models are coupled with real automation hardware. This allows control and automation systems to be tested under realistic, dynamic process conditions before they are used on a real plant. In this way, control strategies can be evaluated at an early stage and the development of flexible chemical plants powered by renewable energy can be accelerated.
Learn more about the HyControl project and the use of HiL testing for flexible chemical processes in our blog article.
Supermarket refrigeration CO2 cycle concepts
Emerson develops components and systems for supermarket refrigeration. Due to its environmental benefits CO2 as refrigerant is becoming more and more important in this sector. But compared to traditional refrigerants the thermodynamic properties of CO2 are totally different (high pressures and low critical temperature). Designing efficient CO2 cycles is challenging and there are many different cycle concepts proposed. Together with Emerson experts we have developed simulation models for a number of different concepts and run a simulation study to compare the seasonal efficiency of these cycles.
Eric Winandy et al.: Assessment of the seasonal efficiency of different CO2 booster architectures for different climates. DKV Jahrestagung, 2018
OUR OFFER
Hardware in the Loop Tests for Thermal Systems with TLK
TIL Suite - The library for thermodynamic systems
- Create real-time models
- Fast material data calculation
- Models exportable as C code (FMI)
- Robust even with flow reversal and zero mass flow
Support in setting up your internal processes
- Selection of suitable HiL software and hardware
- Development of a modelling process and training of your team
- Analysis and solution of numerical problems
- Sharing of experience and best practices
Creation of real-time capable and robust system models
- Complete model creation
- Evaluation of measurement data and data sheets of individual components
- Parameter identification
Tested tool chains with established HiL solutions
- dSPACE, Mathworks/Speedgoat
- Frequent compatibility tests for software updates
- Close contact to the technical developers
WHY TLK ENERGY
Fast and robust models for thermodynamic systems
TIL Suite: Our special library for thermodynamic systems
We have co-developed the TIL Suite together with our partner company TLK Thermo over the last 15 years and established it worldwide. With the latest methods, we can also robustly calculate zero mass flow and flow reversal.
Expertise in thermodynamics and numerics
In HiL tests, Euler solvers with a fixed step size are standard. For thermodynamic systems, this quickly reaches its limits. We use numerical differential equation solvers with variable step size. This way we can achieve 100 % robustness.
FMI interface: Use the software of your choice
Thanks to the FMI interface, our models are compatible with HiL software from various suppliers such as dSPACE or Mathworks/Speedgoat. You can easily integrate our models into your existing in-house solutions.
Our experts in Hardware in the Loop Testing
Dr.-Ing.
Manuel Gräber
Expert for dynamic system simulation, control engineering & HiL
Dr. rer. nat.
Raphael Hornung
Specialized in simulation, HiL & thermophysical property calculations
M.Sc.
Felix Brandl
Focused on Sim.TLK, FMU integration, co-simulation & HiL
How we start working with our customers
Initial Meeting
In a brief conversation, we get to know your needs, goals and general requirements. No preparation is required.
2
Technical Analysis
In a follow-up meeting with one of our experts, we take a closer look at your specific questions, existing tools and possible solution approaches.
Agile Pilot Project
We develop tailored simulation models for HiL testing and support the HiL setup. Results and next steps are regularly aligned with you.
Let's talk about your project
Your point of contact
Hanna Leder (Account Manager) is your point of contact for the initial consultation. She will discuss the next steps with you and connect you with the right expert.
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