Hybrid test bench

Studying the future of automotive engineering

HAW Hamburg has a new hybrid test bench. Students can use it to investigate new types of automotive drive systems and become even better prepared for the challenges of the job market. Prof. Dr.-Ing. Hanno Ihme-Schramm and Prof. Dr.-Ing. Thomas Netzel explain what the hybrid test bench is and the opportunities and changes it brings with it.

Prof. Hanno Ihme-Schramm (l.) und Prof. Thomas Netzel (r.) stehen vor einem Auto mit Hybridantrieb.

Prof. Hanno Ihme-Schramm (l.) and Prof. Thomas Netzel (r.) can use the new test bench to expand the course offerings.

'For us, the hybrid test bench is an initial milestone. It took three years to implement it. We have learned a great deal and are now happy that we can familiarise the students with the new drive systems, theoretically and practically,' says Dr. Hanno Ihme-Schramm, professor of combustion engines and thermodynamics. The new test bench means the students are now able, for the first time, to investigate not only a purely combustion engine or an electric drive system, but also a so-called hybrid drive system. This is a combination of a classic combustion engine and an electric drive system.

The drive systems study specialisation is changing

The changes in the sector are also reflected in the courses on the topic: 'We started integrating relevant electrical engineering content into the lectures for the drive systems specialisation five years ago. This means that the material on the combustion engine can't be handled as extensively as before in all areas,' says Ihme-Schramm. The Department of Automotive and Aeronautical Engineering also coordinates with industry on an ongoing basis.

One example of this is the model-based motor application. Prof. Dr.-Ing. Thomas Netzel, professor of measurement and control engineering, explains what this means: 'We create a virtual model of a motor, which is used, for example, to help reduce a vehicle's energy consumption. The necessary methodological knowledge and experience in applying it to optimise such complex systems are taught in our department. In this way we've established a good reputation and strong demand in the automotive industry.'

Acquiring drive-systems know-how under real operating conditions

The new test bench is modular, like its digital twin, which simulates the system. The students can acquire up-to-date drive-systems know-how under virtually real operating conditions in a protected lab environment. At the same time, the test bench's system architecture is designed in such a way that current and future topics related to modern drive systems can also be studied.

Additionally, the test bench can be used to illustrate the path from the creation of energy (fuel or electricity) to its transport and its consumption. This so-called efficiency chain shows how much CO2 each type of drive system emits into the atmosphere.

Here the total CO2 balance is considered – that is, how much CO2 is actually generated from the energy production phase (e.g. from wind energy) to the consumption phase (vehicle). The specialist term for this process is 'well-to-wheel'. 'From our perspective, this knowledge is the foundation that drive systems engineers must have for the future. This is the only way the topic of low-CO2 mobility can be advanced sustainably,' says Ihme-Schramm.

Holistic thinking about complex technical systems

Another important element in training future engineers is the promotion of holistic thinking about complex technical systems, says Netzel. The modular design of the test bench is well-suited for this.

The subsystems of the test bench, what they do and how they are applied – from the battery to the drive system, and from the measurement to the evaluation of data – are taught in advance in the lectures. These subsystems work together in the overall test bench system. 'It is important for students to have an overview and, especially, to understand how the subsystems and their functions are interrelated,' explains the professor of measurement and control engineering.

The test bench measurements generate large amounts of data. The students prepare the data, identify the patterns that emerge, and analyse them with a view to relevant results and their causes. These findings are obtained using data science methods. Overall, the integration of the test bench in the degree course and the teaching is designed so that students divide the work among teams and work cooperatively. 'We want to strengthen students' interdisciplinary and soft skills, such as interpersonal, social and methodological competence. These are important prerequisites for future engineers in the automotive industry, as well as in other sectors,' adds Netzel.

Electric cars offer significant benefits in the city, but they have to be accepted and purchased by consumers.

Prof. Dr. Hanno Ihme-Schramm, Department of Automotive and Aeronautical Engineering

What does the future of drive systems engineering look like?

'If we look at the future development of drive systems engineering, I'm convinced that a great deal still needs to happen in the coming years in order to significantly reduce CO2 emissions from cars and meet the limits,' says Ihme-Schramm.

The test bench also offers HAW Hamburg students the opportunity to do research in this area. 'Students have the chance to work within interdisciplinary projects,' says Netzel. Through the department's active exchange with the auto industry, current issues can be taken up and addressed in student projects and final theses. 'This makes the areas of studies and teaching as well as research and transfer more attractive,' explains Netzel.

Ihme-Schramm is convinced: Consumers use cars in different ways – for example, as city cars or for longer trips. This is why the combustion engine will still continue to be needed, though its CO2 footprint could be improved through the use of e-fuels and hydrogen. 'In the city, electric cars offer great advantages, but they also need to accepted and purchased by consumers. In this regard, only renewable energies and the expansion of the charging infrastructure will provide additional assistance. This will certainly be interesting in the coming years.'

Text: Ted Koob



Department of Automotive and Aeronautical Engineering

Prof. Dr. Hanno Ihme-Schramm
Professor of Combustion Engines and Thermodynamics
T +49 40 428 75-7905
hanno.ihme-schramm (@) haw-hamburg.de

Prof. Dr. Thomas Netzel
Professor of Measurement and Control Engineering
T +49 40 428 75-7890
thomas.netzel (@) haw-hamburg.de