---
_id: '29899'
abstract:
- lang: eng
  text: LLC resonant converters are typically unsuitable to be applied for wide voltage-transfer
    ratio applications. With a full-bridge inverter, however, they can be operated
    in a variety of different modulations. Most notably, by permanently turning on
    one MOSFET and turning off the other MOSFET of the same bridge leg, the LLC can
    be operated in half-bridge configuration reducing the gain by a factor of two.
    The resonant capacitor is hereby charged to an average voltage of half the input
    voltage. In this modulation, however, the switch that is permanently turned on
    is stressed by the complete resonant current while exhibiting no switching losses.
    This paper proves that the frequency-doubler modulation can better balance the
    losses among all MOSFETs and should be the preferred mode of operation favored
    over the conventional half-bridge modulation. This paper analyzes the beneficial
    loss distribution, proposes an on-the-fly morphing modulation and discusses potential
    operating strategies to further reduce the junction temperature. Furthermore,
    it is shown that this modulation can also be altered to achieve the asymmetrical
    LLC operation. Experimental measurement results show that the modulation results
    in a substantial decrease of the maximum MOSFET temperature and shows that the
    converter can be smoothly transitioned during operation from full-bridge modulation
    to the frequency-doubler half-bridge operation and back.
author:
- first_name: Philipp
  full_name: Rehlaender, Philipp
  id: '69469'
  last_name: Rehlaender
- first_name: Roland
  full_name: Unruh, Roland
  id: '34289'
  last_name: Unruh
- first_name: Lars
  full_name: Hankeln, Lars
  last_name: Hankeln
- first_name: Frank
  full_name: Schafmeister, Frank
  id: '71291'
  last_name: Schafmeister
- first_name: Joachim
  full_name: Böcker, Joachim
  id: '66'
  last_name: Böcker
  orcid: 0000-0002-8480-7295
citation:
  ama: 'Rehlaender P, Unruh R, Hankeln L, Schafmeister F, Böcker J. Frequency-Doubler
    Modulation for Reduced Junction Temperatures for LLC Resonant Converters Operated
    in Half-Bridge Configuration. In: <i>23rd European Conference on Power Electronics
    and Applications (EPE’21 ECCE Europe)</i>. IEEE; 2021. doi:<a href="https://doi.org/10.23919/EPE21ECCEEurope50061.2021.9570674">10.23919/EPE21ECCEEurope50061.2021.9570674</a>'
  apa: Rehlaender, P., Unruh, R., Hankeln, L., Schafmeister, F., &#38; Böcker, J.
    (2021). Frequency-Doubler Modulation for Reduced Junction Temperatures for LLC
    Resonant Converters Operated in Half-Bridge Configuration. <i>23rd European Conference
    on Power Electronics and Applications (EPE’21 ECCE Europe)</i>. 23rd European
    Conference on Power Electronics and Applications (EPE’21 ECCE Europe), Ghent,
    Belgium. <a href="https://doi.org/10.23919/EPE21ECCEEurope50061.2021.9570674">https://doi.org/10.23919/EPE21ECCEEurope50061.2021.9570674</a>
  bibtex: '@inproceedings{Rehlaender_Unruh_Hankeln_Schafmeister_Böcker_2021, title={Frequency-Doubler
    Modulation for Reduced Junction Temperatures for LLC Resonant Converters Operated
    in Half-Bridge Configuration}, DOI={<a href="https://doi.org/10.23919/EPE21ECCEEurope50061.2021.9570674">10.23919/EPE21ECCEEurope50061.2021.9570674</a>},
    booktitle={23rd European Conference on Power Electronics and Applications (EPE’21
    ECCE Europe)}, publisher={IEEE}, author={Rehlaender, Philipp and Unruh, Roland
    and Hankeln, Lars and Schafmeister, Frank and Böcker, Joachim}, year={2021} }'
  chicago: Rehlaender, Philipp, Roland Unruh, Lars Hankeln, Frank Schafmeister, and
    Joachim Böcker. “Frequency-Doubler Modulation for Reduced Junction Temperatures
    for LLC Resonant Converters Operated in Half-Bridge Configuration.” In <i>23rd
    European Conference on Power Electronics and Applications (EPE’21 ECCE Europe)</i>.
    IEEE, 2021. <a href="https://doi.org/10.23919/EPE21ECCEEurope50061.2021.9570674">https://doi.org/10.23919/EPE21ECCEEurope50061.2021.9570674</a>.
  ieee: 'P. Rehlaender, R. Unruh, L. Hankeln, F. Schafmeister, and J. Böcker, “Frequency-Doubler
    Modulation for Reduced Junction Temperatures for LLC Resonant Converters Operated
    in Half-Bridge Configuration,” presented at the 23rd European Conference on Power
    Electronics and Applications (EPE’21 ECCE Europe), Ghent, Belgium, 2021, doi:
    <a href="https://doi.org/10.23919/EPE21ECCEEurope50061.2021.9570674">10.23919/EPE21ECCEEurope50061.2021.9570674</a>.'
  mla: Rehlaender, Philipp, et al. “Frequency-Doubler Modulation for Reduced Junction
    Temperatures for LLC Resonant Converters Operated in Half-Bridge Configuration.”
    <i>23rd European Conference on Power Electronics and Applications (EPE’21 ECCE
    Europe)</i>, IEEE, 2021, doi:<a href="https://doi.org/10.23919/EPE21ECCEEurope50061.2021.9570674">10.23919/EPE21ECCEEurope50061.2021.9570674</a>.
  short: 'P. Rehlaender, R. Unruh, L. Hankeln, F. Schafmeister, J. Böcker, in: 23rd
    European Conference on Power Electronics and Applications (EPE’21 ECCE Europe),
    IEEE, 2021.'
conference:
  end_date: 2021-09-10
  location: Ghent, Belgium
  name: 23rd European Conference on Power Electronics and Applications (EPE'21 ECCE
    Europe)
  start_date: 2021-09-06
date_created: 2022-02-20T21:29:48Z
date_updated: 2023-02-09T11:01:11Z
department:
- _id: '34'
- _id: '52'
doi: 10.23919/EPE21ECCEEurope50061.2021.9570674
keyword:
- Resonant converter
- High frequency power converter
- Switched-mode power supply
- Converter control
- Control methods for electrical systems
language:
- iso: eng
main_file_link:
- url: https://ieeexplore.ieee.org/abstract/document/9570674
publication: 23rd European Conference on Power Electronics and Applications (EPE'21
  ECCE Europe)
publication_identifier:
  isbn:
  - 978-9-0758-1537-5
publication_status: published
publisher: IEEE
status: public
title: Frequency-Doubler Modulation for Reduced Junction Temperatures for LLC Resonant
  Converters Operated in Half-Bridge Configuration
type: conference
user_id: '34289'
year: '2021'
...