LLC Converter with Integrated Magnetics Application for 48V Rack Architecture in Future Data Centers

In this paper, magnetic integration methods are proposed for regulated and unregulated LLC converters. The proposed magnetic structures besides the soft switching capabilities of the LLC converters and outstanding performance of wide band gap devices (WBG) help to operate at high switching frequency while achieving high-efficiency and high-power-density. The proposed magnetic structure is utilized for designing various point of load (POL) converters solutions in the 48V rack architecture for future datacenters. First, an unregulated LLC converter is designed for two-stage 48V POL solution, the designed converters can maintain a high efficiency above 98% with power density exceeding the 1200 W/in
³
. Second, a regulated LLC converter is utilized in a quasi-parallel single-stage 48V POL that can achieve a high-efficiency of 95% with power density of 700W/in
³
. Experimental prototypes have been built and performance comparison between the two solutions is provided.