Single-Stage High-Efficiency 48/1 V Sigma Converter With Integrated Magnetics

A high-efficiency, high-power-density Sigma converter for a 48 V rack architecture in data centers is proposed in this paper. The Sigma converter is a quasi-parallel converter that uses a high-efficiency unregulated converter to deliver the bulk power to the load. A small buck converter is responsible for regulating the output voltage with prescribed dynamic responses. A design guideline for Sigma converter with integrated magnetics is provided in this paper. The unregulated converter is an LLC converter designed with a printed circuit board (PCB) winding matrix transformer, a structure which integrates four elemental transformers into one core. The buck converter is designed with discrete gallium nitride (GaN) devices and a PCB winding inductor. The proposed Sigma converter operates at 48 V input and 1 V-80 A output and can achieve a power density of 420 W/in3 as well as a peak efficiency of 94%.

[1]  Fred C. Lee,et al.  LLC Resonant Converter With Matrix Transformer , 2014 .

[2]  Stefano Saggini,et al.  Isolated resonant full-bridge converter with magnetic integration , 2017, 2017 IEEE Applied Power Electronics Conference and Exposition (APEC).

[3]  F.C. Lee,et al.  Σ/sigma DC/DC conversion for computing and telecom applications , 2008, 2008 IEEE Power Electronics Specialists Conference.

[4]  F. C. Lee,et al.  High frequency bus converter with low loss integrated matrix transformer , 2012, 2012 Twenty-Seventh Annual IEEE Applied Power Electronics Conference and Exposition (APEC).

[5]  Fred C. Lee,et al.  Design and Optimization of a 380–12 V High-Frequency, High-Current LLC Converter With GaN Devices and Planar Matrix Transformers , 2016, IEEE Journal of Emerging and Selected Topics in Power Electronics.

[6]  Fred C. Lee,et al.  Startup and control of high efficiency 48/1V sigma converter , 2017, 2017 IEEE Energy Conversion Congress and Exposition (ECCE).

[7]  Fred C. Lee,et al.  High efficiency two-stage 48V VRM with PCB winding matrix transformer , 2016, 2016 IEEE Energy Conversion Congress and Exposition (ECCE).

[8]  Fred C. Lee,et al.  High-Efficiency High-Power-Density LLC Converter With an Integrated Planar Matrix Transformer for High-Output Current Applications , 2017, IEEE Transactions on Industrial Electronics.

[9]  Khai D. T. Ngo,et al.  Modeling of losses in a sandwiched-winding matrix transformer , 1995 .

[10]  Fred C. Lee,et al.  Two-Stage 48 V-12 V/6 V-1.8 V Voltage Regulator Module With Dynamic Bus Voltage Control for Light-Load Efficiency Improvement , 2017, IEEE Transactions on Power Electronics.

[11]  Xinbo Ruan,et al.  Input-series output-parallel multiple output converter , 2014, 2014 IEEE Applied Power Electronics Conference and Exposition - APEC 2014.

[12]  Debaprasad Kastha,et al.  Quasi-Parallel Voltage Regulator Topology for Powering Laptop Processors , 2017, IEEE Transactions on Power Electronics.

[13]  Maurizio Salato.  Datacenter power architecture: IBA versus FPA , 2011, 2011 IEEE 33rd International Telecommunications Energy Conference (INTELEC).

[14]  Fred C. Lee,et al.  A novel current-tripler DC/DC converter , 2003, IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03..

[15]  Chenhao Nan,et al.  Switched Tank Converters , 2019, IEEE Transactions on Power Electronics.

[16]  J. Strydom,et al.  Understanding the effect of PCB layout on circuit performance in a high frequency gallium nitride based point of load converter , 2013, 2013 Twenty-Eighth Annual IEEE Applied Power Electronics Conference and Exposition (APEC).

[17]  F.C. Lee,et al.  A current-tripler dc/dc converter , 2004, IEEE Transactions on Power Electronics.

[18]  F.C. Lee,et al.  High efficiency quasi-parallel Voltage Regulators , 2008, 2008 Twenty-Third Annual IEEE Applied Power Electronics Conference and Exposition.

[19]  Paolo Mattavelli,et al.  An Isolated Quasi-Resonant Multiphase Single-Stage Topology for 48-V VRM Applications , 2018, IEEE Transactions on Power Electronics.

[20]  Fred C. Lee,et al.  High frequency bus converter with integrated matrix transformers for CPU and telecommunications applications , 2010, 2010 IEEE Energy Conversion Congress and Exposition.

[21]  F.C. Lee,et al.  1-MHz self-driven ZVS full-bridge converter for 48-V power pod and DC/DC brick , 2005, IEEE Transactions on Power Electronics.

[22]  Fred C. Lee,et al.  High-efficiency high-power-density 48/1V sigma converter voltage regulator module , 2017, 2017 IEEE Applied Power Electronics Conference and Exposition (APEC).

[23]  Chenhao Nan,et al.  A high efficiency resonant switched-capacitor converter for data center , 2017, 2017 IEEE Energy Conversion Congress and Exposition (ECCE).

[24]  Fred C. Lee,et al.  48-V Voltage Regulator Module With PCB Winding Matrix Transformer for Future Data Centers , 2017, IEEE Transactions on Industrial Electronics.