D24.1 - A Light-Load Efficiency-Optimized Modulation for Integrated Buck-Boost-LLC Converter Under Wide Input-Voltage Range

Thursday, March 26, 2026

12:00 PM - 1:45 PM CT

Location: Hemisfair Ballroom

Technical Dialogue Presenter(s)

Yang Zhang (he/him/his)

China-EU Institute for Clean and Renewable Energy, Huazhong University of Science and Technology

Presentation

Co-Author(s)

CL

Caifeng Liu

China Electric Power Planning and Engineering Institute
WH

Wei Huang (she/her/hers)

School of Electrical and Electronic Engineering, Huazhong University of Science and Technology
XZ

Xudong Zou

Power Electronics and Energy Management Key Laboratory, Ministry of Education of China
YK

Yong Kang

School of Electrical and Electronic Engineering, Huazhong University of Science and Technology

Integrated buck-boost-LLC (IBBLLC) converter is suitable for wide voltage range and high frequency applications. However, conventional modulation strategies face challenges including soft-switching failure and significant transformer core loss proportion under light-load conditions, resulting in efficiency degradation over wide input-voltage range. Therefore, this paper proposes a dual PWM plus phase-shift (DPPS) modulation, which introduces the shared-bridge duty cycle as an additional control degree of freedom to address the light-load issues. Experimental results from a 300 W prototype demonstrate the superiority of the proposed scheme.