Hybrid Resonant Converter-Based 8:1 Bus Converter With 3.5 kWin³ and 98.6-Efficient for 48 V Data-Center Power Systems

A hybrid resonant converter with a 1:1 turn-ratio autotransformer and two 2:1 turn-ratio transformers is proposed to achieve an 8:1 bus converter for 48V data-center power systems. Compared with conventional resonant converters, the turns and losses of the transformer windings of the proposed hybrid resonant converter are reduced. A matrix transformer with PCB windings is proposed to integrate the autotransformer and two transformers into one magnetic core. As a result, both the volume and losses of the magnetic core are reduced. A 40-60 V input, 5 V-7.5 V/200A output prototype is designed and tested. 3.5 kW/in(3) power-density and 98.6% efficiency are achieved with the proposed solutions.