A Dual-Bridge LLC Resonant Converter with Fixed-Frequency PWM Control for Wide Input Applications

Sun Xiaofeng, Xiaohua Li, Yanfeng Shen, Baocheng Wang, Xiaoqiang Guo

Research output: Contribution to journalJournal articleResearchpeer-review

138 Citations (Scopus)


This paper proposes a dual-bridge (DB) LLC resonant converter for wide input applications. The topology is an integration of a half-bridge (HB) LLC circuit and a full-bridge (FB) LLC circuit. The fixed-frequency PWM control is employed and a range of twice the minimum input voltage can be covered. Compared with the traditional pulse frequency modulation (PFM) controlled HB/FB LLC resonant converter, the voltage gain range is independent of the quality factor and the magnetizing inductor has little influence on the voltage gain, which can simplify the parameter selection process and benefit the design of magnetic components as well. Over the full load range, zero voltage switching (ZVS) and zero current switching (ZCS) can be achieved for primary switches and secondary rectifier diodes, respectively. Detailed analysis on the modulation schedule and operating principle of the proposed converter is presented along with the converter performance. Finally, all theoretical analysis and characteristics are verified by experimental results from a 120V-240V input 24V/20A output converter prototype.
Original languageEnglish
JournalI E E E Transactions on Power Electronics
Issue number1
Pages (from-to)69 - 80
Number of pages12
Publication statusPublished - Jan 2017


  • LLC
  • Dual-bridge
  • Fixed-frequency
  • Wide input voltage range


Dive into the research topics of 'A Dual-Bridge LLC Resonant Converter with Fixed-Frequency PWM Control for Wide Input Applications'. Together they form a unique fingerprint.

Cite this