A High-Density 5kW 800V to 48V DC/DC Converter for Vehicle Applications

In this paper, a high density 5 kW LLC resonant converter is proposed to enable a single stage dc to dc conversion from 800V to 48V for vehicle applications. The proposed LLC converter with hybrid winding structure features high efficiency and high power density. The primary winding is implemented by using vertically oriented copper foil embedded in a 3Dprinted bobbin to reduce the AC losses and the parasitic capacitance. The secondary winding, synchronous rectifiers (SR) and output capacitors are integrated in the same printed circuit board. In addition, a direct cooling approach using an additive manufactured (AM) manifold is proposed to further increase the power density of the converter. To validate the effectiveness of the proposed LLC design, a converter prototype has been developed with comprehensive experimental studies undergoing. Preliminary experimental results are presented in this digest. With the AM manifold, the prototype has achieved a power density over 5 kW/L.