GaN Based High-Density Unregulated 48 V to x V LLC Converters with ≥ 98% Efficiency for Future Data Centers
Konferenz: PCIM Europe 2019 - International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management
07.05.2019 - 09.05.2019 in Nürnberg, Deutschland
Tagungsband: PCIM Europe 2019
Seiten: 8Sprache: EnglischTyp: PDFPersönliche VDE-Mitglieder erhalten auf diesen Artikel 10% Rabatt
Ahmed, Mohamed H.; Lee, Fred C.; Li, Qiang (Center for Power Electronics Systems (CPES), The Bradley Department of Electrical and Computer Engineering, Virginia Tech, USA)
Rooij, Michael de; Reusch, David (Efficient Power Conversion (EPC), USA)
The two-stage 48 V voltage regulator module (VRM) with an unregulated first stage DC/DC converter providing intermediate bus voltage, followed by a multi-phase buck converter, has proven to be a scalable and efficient approach for 48 V rack architecture in data centers. In this work, eGaN(r) based first stage unregulated LLC converters with integrated magnetics are proposed. The converters are designed with fixed transformation ratios of (4:1) and (8:1). They provide a continuous power of 900 W, with maximum efficiencies of 98.4 % and 98.0 % in high-power-densities of 1600 W/in3 (98 KW/liter) and 1200 W/in3 (74 KW/liter), respectively. The bus voltage variation is evaluated to maximize the overall efficiency of the 48 V VRM.