Electric propulsion drive trains – high efficient and robust electric propulsion drives including battery buffering system for working vehicles and cars


The market of electrical powered vehicles and cars will grow in the future rapidly, mainly due to the energy and environmental problems. High efficiency is besides robustness a key criterion for competitiveness of these vehicles and cars, especially for the main energy consuming unit, the electric propulsion drive. To achieve a high efficiency, a sophisticated low-loss power electronic and machine as well as a battery buffering system is necessary. The buffering system avoids high currents in the battery during charging and discharging and thus can improve the efficiency.

To enable this enhanced efficiency, special new power electronic circuits and control methods have to be developed or known ones to be applied and developed further. Base must be a severe knowledge of power electronics and electrical drives.

In Schleswig-Holstein and Southern Denmark there are several companies working on working vehicles and components for electric cars. Working vehicles can be for example forklifts or garbage trucks. The results of the research moreover can also be used for drive trains in other applications as cranes, lifts and so on. Other companies are working on power electronics, where some are delivering components to the automobile industry and others are planning to do it. So there is a good chance to enforce the technical and product competence of these companies by means of the applied research in this project.


Objectives and results:

Based on this background applied research work will be carried out with the objective to optimize the efficiency and the robustness of electrical propulsion drives of electric vehicles and cars. Principally methodologies shall be investigated, analyzed and brought into practical application that can be used in the different applications. The research work will be done at the Christian-Albrechts-University of Kiel in Kiel Germany. There research has been carried out in some of these fields for other applications and other requirements, so the work can start from this point and thus a good scientific and technical environment is guaranteed. The work will be done in cooperation with the companies in the region working on electric vehicles, components for propulsion drives or on drives, planning to deliver for vehicle or car industry. The following main results are to be attained, all in close cooperation with relevant industry:

  1. Determination and analysis of potential efficiency optimization measures in drive trains for electrical powered vehicles and cars. Selection of promising measures for practical research work. Adaption of the research plan to this detailed analysis results.

  2. Deep analytical investigation of the selected measures for efficiency optimization. Stating improvement in efficiency to be reached and necessary additional effort to be spent. Selection of promising measures.
  3. Practical investigation of these measures in test power electronic circuits and test drive trains in the laboratory. Stating improvement in efficiency to be reached and necessary additional effort to be spent. Selection of promising measures.
  4. Setting up design guidelines for the implementation of the promising analyzed measures for efficiency optimization in propulsion drive trains for electric vehicles and cars.
  5. Propagation of the results by means of scientific papers and other media.


Responsible Partner:

Christian-Albrechts-Universität zu Kiel (CAU)
Kaiserstrasse 2, 24143 Kiel

Prof. Dr. Friedrich Wilhelm Fuchs

+49 431 880-6100