Highly Variable System Test Bench for Hybrid Electric Drives



Timm Fahrbach

Research Associate


+49 241 80-24221



Hybrid drives can be a useful step towards reducing greenhouse gas emissions. Combining the advantages of combustion engines with those of electric machines, they can be driven with low emissions and low fuel consumption. Adverse factors are an increasing complexity and thereby increasing system costs, which frequently are decisive for the purchase of smaller vehicles in particular.

At the MMP of RWTH Aachen University, a hybrid drive is being developed based on the interconnection of a combustion engine and an electric machine via a planetary gearbox with passive switching elements. This enables the implementation of a highly efficient and cost-effective hybrid drive with outstanding drivability.

In the already granted project "HELDA", this drive is being researched in an all-terrain vehicle with partly tailor-made and partly market-available components. The initial results are promising, but it has also proved that a detailed knowledge of the individual components and their mutual interaction is necessary for a well-founded system design. Furthermore, the use of commercially available components represents a severe limitation regarding installation space and function.

Within the scope of the research project "VISBED", individual components of the powertrain will be measured in different sizes with the aid of a test bench. This is a necessary step in order to be able to simulate their behavior and interaction with the system. For this purpose, simulation models must be developed and validated that accurately reproduce the operating point and temperature-dependent efficiency. Based on these findings, a framework for system design will be set up in order to be able to design the drive with customized components for different performance classes in a well-founded manner. To ensure the test bench can be operated cost-efficiently in the future, operation without complex and expensive conversion measures and simple handling has to be implemented.



Ministerium für Wirtschaft, Innovation, Digitalisierung und Energie des Landes Nordrhein-Westfalen