High-power unidirectional and bidirectional dc-dc converters with galvanic isolation have been expected to play an important role as an interface with battery charging and energy-storage systems, as well as in integrating them into medium-voltage and/or low-voltage dc grids. Power electronics scientists and engineers are paying more attention to bidirectional isolated dc-dc converters as the SiC-MOSFET/SBD devices available on the market are getting better in performance and lower in cost.

 　This research has designed, built, and tested the 850-V 100-kW 16-kHz bidirectional isolated dc-dc converter using the latest 1.2-kV 400-A SiC-MOSFET/SBD H-bridge modules. The authors have proposed a concept of intermittent operation with continuous-current mode (CCM) for reducing switching losses in partial loads. Experimental results have confirmed that the overall conversion efficiency from the dc input to the dc output was as high as 99.3% at the rated power of 100 kW, and 99.2% at a 10% load of 10 kW.

Experimental circuit system of a bidirectional isolated dc-dc converter.

References

R. Haneda and H. Akagi, "Design and Performance of the 850-V 100-kW 16-kHz Bidirectional Isolated DC-DC Converter Using SiC-MOSFET/SBD H-Bridge Modules," in IEEE Transactions on Power Electronics, vol. 35, no. 10, pp. 10013-10025, Oct. 2020, 10.1109/TPEL.2020.2975256