On the search for more power efficiency in electric powertrains

June 24, 2015 // By Christoph Hammerschmidt
In a joint R&D efforts, ten carmakers and suppliers intend do improve the overall energy efficiency of all types of electric powertrains, be it for battery electric cars, plug-in hybrids or small transport vehicles. A big focus of the project lies on semiconductors, and that’s perhaps why chipmaker Infineon has the project lead.

Within the next three years, the HV-ModAL project aims at creating a modular system toolbox, which is suitable for a wide range of electric cars from any manufacturer. With the move the partners hope to expand the market position of the German automotive industry in the field of electric vehicles – despite several attempts, the German carmakers have yet failed to gain a market position with their electric vehicles comparable to their conventional cars.

The power bandwidth for the toolbox will initially cover the range from 50 to 250 kW. Today, 125 kW and a range of 150 km are typical values for battery-electric cars.

During the first project stage, the research partners intend to come to an understanding of electric drive platforms to be shared throughout the automotive value chain. Then they will conduct extensive concept and component research to determine the individual components that can be best coordinated with each other for such electric drive platforms.

One of the research topics to be addressed will be the development of IGBT power modules for high-power drives up to 250 kW and high voltages of up to 900 V, modular multi-level DC/DC converters, batteries with integrated DC/DC converters, and system components for batteries with voltages of 600 V and more. To describe and define these components and subsequently matching them to one another the partners are devising a common, flexible system simulation model for different vehicle platforms. To verify the theoretical results, optimized components and architectures will be built as demonstration models and tested. The results will form the basis for the HV-ModAL system designs, and ultimately the modular system toolbox for the broadest possible range of electric drives.

The project brings ten partners together, including carmakers BMW and Daimler, supplier Robert Bosch GmbH, drive system developer AVL, the Fraunhofer Institute for Integrated Systems and Device Technology (IISB) in Erlangen, the university of Hannover, the Universität der Bundeswehr München and