skip to main content

Explore Research Products in the NSF-PAR

  • NSF Public Access
  • Search Results
  • A Regulated 48V-to-1V/100A 90.9%-Efficient Hybrid Converter for POL Applications in Data Centers and Telecommunication Systems
Title: A Regulated 48V-to-1V/100A 90.9%-Efficient Hybrid Converter for POL Applications in Data Centers and Telecommunication Systems
This paper describes the topology, fundamental operations, and key characteristics of a Dual-Phase Multi-Inductor Hybrid (DP-MIH) Converter for Point of Load (POL) telecommunication and data center applications. The circuit topology employs a unique configuration of switched-inductor and capacitor pairs to achieve complete soft charging and native voltage balancing of flying capacitors regardless of mismatches and variations in capacitor and inductor values. The converter topology and its operation are verified by a five-level DP-MIH converter prototype capable of delivering maximum load of 100A at 1V-5V regulated output voltages from a 48V input supply. It achieves 90.9% peak efficiency and 440 w/in3 power density for 48V-to-1V conversion and 95.3% and 2200W/in3 for a 48V-to-5V conversion.  more » « less
Award ID(s):
1810470
NSF-PAR ID:
10094095
Author(s) / Creator(s):
;
Date Published:
Journal Name:
2019 IEEE Applied Power Electronics Conference and Exposition (APEC)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ( , 2019 IEEE Applied Power Electronics Conference and Exposition (APEC))
    This paper presents a new Multi-Phase Multi-Inductor Hybrid (MP-MIH) converter that features high efficiency at large conversion ratios, while operating the switches with duty cycles larger than state-of-the-art hybrid topologies. In this converter, the capacitors are soft-charged and soft- discharged through three inductors operated in three interleaving phases. An experimental six-level three-phase converter prototype achieves 94.6% peak efficiency and 425 W/in3 power density for conversions from 48V to 1V-2V at loads of up to 40A. This multi-phase multi-inductor hybrid converter architecture can be extended to any number of switched-capacitor network levels to support wide range of input and output voltages and load currents in data centers, telecommunication and other high- performance digital systems. 
    more » « less
  2. ; ; ( , IEEE Journal of Emerging and Selected Topics in Power Electronics)
    This paper presents a dual-inductor hybrid (DIH) converter that is capable of efficient non-isolated DC-DC con- versions with extremely large voltage conversion ratios. The converter topology combines a switched-capacitor network and two interleaved inductors, that supports simple duty-cycle control for output regulation. In order to achieve complete soft charging for all flying capacitors, a method to optimally size the capacitors has been proposed and verified. A detailed analysis on the two inductor currents revealing a new and simple method to modulate them and its impacts on output regulation and efficiency are also provided and demonstrated in experiments. Employing the converter topology and design methods, a DIH converter prototype is implemented and measured for a wide range of operating voltages, providing a 1V-2V output from a 48-V input and a 1V-5V output from a 150V input with output currents up to 20A. The converter achieves 94.3% peak efficiency at 48V- to-2V/7A conversion and 93.7% at 150V-to-5V/18A conversion. 
    more » « less
  3. ; ; ; ; ( , 2019 IEEE Applied Power Electronics Conference and Exposition (APEC))
    This paper presents a new Multiphase Dual Inductor Hybrid (MP-DIH) Converter for application in data center and telecommunication systems. The converter is based on addition of two output filter inductors to a Dickson switched-capacitor converter. The inductors are operated in multiple phases that are non-overlapped and evenly distributed over one switching cycle, completely soft-charging all flying capacitors even in the presence of practical capacitor mismatches and voltage ripples. In this converter operation, each branch of the switched-capacitor network is activated individually in one charging phase, and two interleaved inductors are employed to softly charge and discharge the capacitors to achieve high efficiency without any complex capacitor sizing or split phase operation. To verify the topology and its soft-charging advantages, a 48V-to-1.8V 20W experimental converter prototype is constructed. The converter achieves 92.4% peak efficiency for 40V-to-1.8V conversion and 92.1% peak efficiency for 48V-to-1.8V conversion at 4A load, and with 20% capacitance variations. 
    more » « less
  4. ; ( , IEEE International Solid- State Circuits Conference (ISSCC))
    null (Ed.)
    Efficient high-conversion-ratio power delivery is needed for many portable computing applications which require sub-volt supply rails but operate from batteries or USB power sources. In such applications, the power management unit should have a small volume, area, and height while providing fast transient response. Past work has shown favorable performance of hybrid switched-capacitor (SC) converters to reduce the size of needed inductor(s), which can soft-charge high-density SC networks while supporting efficient voltage regulation [1-5]. However, the hybrid approach has its own challenges including balancing the voltage of the flying capacitor and achieving safe but fast startup. Rapid supply transients, including startup, can cause voltage stress on power switches if flying capacitors are not quickly regulated. Past approaches such as precharge networks [3] or fast balancing control [5] have startup times that are on the order of milliseconds. This paper presents a two-stage cascaded hybrid SC converter that features a fast transient response with automatic flying capacitor balancing for low-voltage applications (i.e., 5V:0.4 to 1.2V from a USB interface). The converter is nearly standalone and all gate drive supplies are generated internally. Measured results show a peak efficiency of 96.9%, <; 36mV under/overshoot for 1A/μs load transients, and self-startup time on the order of 10μs (over 100× faster than previous works). 
    more » « less
  5. ; ; ; ; ; ( , 2019 20th Workshop on Control and Modeling for Power Electronics (COMPEL))
    This paper presents a modeling method to accurately predict DC and ripple values of flying capacitor voltages and inductor currents in hybrid converters by recognizing a key relationship between median and average values of these state variables. The method is demonstrated for the Dual-Phase Multi-Inductor Hybrid (DP-MIH) converter and 3-Level Buck converter. Analytical details and intuitive explanations are presented for the well-known balancing problem of flying capacitor voltages and inductor current fluctuations in hybrid converters. Simulation results for the converters at different operating conditions are provided to verify the method and analytical results. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email