Design Methodology of High-Power Density Converter with Wide Input Voltage Range

High-power density and high efficiency have always been the pursuit of power supplies. In the industry, the two-stage converter is widely employed in various applications for its inherent advantages, such as high reliability and simple control. In this article, the design methodology of high-power-density converters is given and presented for the two-stage converters systematically, including topology comparison, magnetic integration, and circuit parameters design. First, this article evaluates and compares three different topologies and the Boost-DCX configuration with low-component stress factors is selected. Then, to shrink the magnetic size, a matrix core is proposed to integrate two coupled inductors and one transformer. In comparison with the traditional magnetic design method using two E-I cores, the footprint of proposed core is reduced by around 30%. Finally, the proposed methodology is employed in a two-stage isolated converter for datacenter applications. A 1-kW prototype, from 38–72-V input to 53.5-V output, demonstrates a peak efficiency of 95.6% and a power density of 126W/in³.