The electrification of road transport, as an essential and fundamental step towards climate neutrality, poses new challenges not only on the vehicle side, but also on the infrastructure side. Electrification affects not only passenger cars, as might be expected at first glance, but also the small, medium and heavy-duty vehicles needed for freight transport, as well as long-distance and local buses. In particular, the high power requirements for rapid charging of these heavy vehicles pose new challenges, including for the power electronic converters that are the focus of this work. High efficiency at low cost are the key criteria. In this thesis, DC-DC converters are investigated and optimized with respect to these criteria using an exemplary future charging park. After a brief introduction to current charging technology and an outlook on future charging technology, different scenarios for charging parks at highway service areas are examined, in particular with regard to the distribution grid and the power electronic converters. The resulting constraints, such as voltage and power levels, then form the basis for following design and optimization of the DC-DC converters for the chargers. Four different isolated DC-DC converter topologies suitable for this high power application are investigated in this work: Phase Shift Full Bridge (PSFB) converter, LLC converter, Dual Active Bridge (DAB) converter and the converter referred to here as the Two-Stage Converter (TSC, isolation and power flow control are implemented separately). These are presented and examined in detail so that a script-based design can be carried out for the individual components and ultimately for the overall system. This type of design makes it possible to identify all valid solutions for a wide range of input parameters. In a second step, these solutions are evaluated against the efficiency and cost criteria mentioned above. Through this multi-objective optimization, a solution can be found that represents a global optimum. The thesis concludes with the investigation, design and implementation of a modified PSFB converter topology in which the switching between parallel and series connection of two secondary sides is realized by means of semiconductor switches. This allows a more flexible coverage of different battery types and a higher efficiency than with mechanical switches through suitable control.     «

The electrification of road transport, as an essential and fundamental step towards climate neutrality, poses new challenges not only on the vehicle side, but also on the infrastructure side. Electrification affects not only passenger cars, as might be expected at first glance, but also the small, medium and heavy-duty vehicles needed for freight transport, as well as long-distance and local buses. In particular, the high power requirements for rapid charging of these heavy vehicles pose new cha...     »