A Below-Resonant-Frequency Phase-Shift Modulation Method for <i>CLLC</i> Converters With Enhanced Light-Load Efficiency
This letter introduces a below-resonant-frequency phase-shift modulation (BRFPSM) method to improve the light-load efficiency of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CLLC</i> converters. Traditional <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CLLC</i> converters using pulse frequency modulation face challenges, such as high nonactive power and turn-<sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> current at light load in a below-resonant-frequency region. In this work, to analyze the BRFPSM, simplified time-domain model is employed to obtain accurate turn-<sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> current and gain–frequency–phase shift relationship. Experimental validation with a 1.5-kW <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CLLC</i> converter demonstrates the effectiveness of the method showing improved efficiency at light loads.
Authors
- Zhiyong Zeng (ORCID: https://orcid.org/0000-0002-4924-241X)
- Xiongfeng Fang (ORCID: https://orcid.org/0000-0001-6544-2721)
- Longteng Jiao
- Cheng Wang (ORCID: https://orcid.org/0000-0003-2230-9386)
- Lei Li (ORCID: https://orcid.org/0000-0001-5593-4458)
Institutions
- Nanjing University of Science and Technology (CN)
Publication Details
- Journal
- IEEE Transactions on Power Electronics
- Published
- 2025-02-05
- DOI
- https://doi.org/10.1109/tpel.2025.3538695
- Primary Topic
- Magnetic Properties and Synthesis of Ferrites
- Type
- article
- Field-Weighted Citation Impact
- 0.00