This presentation will provide an update on our current project: designing a cooler for a high power (5 MW) MVDC converter for offshore wind turbines applications. A number of constraints are imposed, mainly related to a limited volume, environmental, safety and health regulations, and of course cooling performance. Indeed, as we presented last year (ATW 2017), the silicon carbide power semiconductors used in this converter should operate at a junction temperature lower than 100 °C for better efficiency.

This article presents the design, the fabrication, and the test of an isolated DC-DC converter for renewable energy applications. The converter is based on the Dual Active Bridge topology and uses silicon carbide power semiconductors and a medium frequency transformer. The design process covers hardware ranging from the semiconductor die to the complete power converter. For the control, a rapid prototyping approach was used. The experimental validation of the 100 kW prototype is presented.

This paper presents a methodology to optimize the sizing of such power converters in order to compare different topologies for a given application. The proposed procedure maximises the efficiency of the converter under a limited volume.

This paper focuses on analytical or semi-analytical calculation techniques to be integrated into a medium frequency transformer optimization process.

In the new electrical grids, series/parallel converters architectures can be considered for medium and high voltage power conversion. Dual Active Bridge (DAB) topology is a serious candidate to be implemented within these converters.