LLC resonant converter based on PFM-Burst hybrid control
Konferenz: MEMAT 2022 - 2nd International Conference on Mechanical Engineering, Intelligent Manufacturing and Automation Technology
07.01.2022 - 09.01.2022 in Guilin, China
Tagungsband: MEMAT 2022
Seiten: 5Sprache: EnglischTyp: PDF
Autoren:
Rao, Gang (Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering, Wuhan University of Science and Technology, Wuhan, Hubei, China & Precision Manufacturing Institute, Wuhan University of Science and Technology, Wuhan, Hubei, China)
Zhang, Ziyuan (Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering, Wuhan University of Science and Technology, Wuhan, Hubei, China)
Inhalt:
Aiming at the problem that LLC resonant converter uses pulse frequency modulation (PFM) to control the output voltage, it is difficult to modulate at very light load and no load, and a hybrid control mode based on pulse frequency-burst control (PFM-Burst) is proposed to realize the regulation of the output voltage of the LLC resonant converter. First, the fundamental wave analysis method is used to analyze the characteristics and shortcomings of LLC resonant converters under PFM modulation. According to the characteristics of Burst control, a PFM-Burst hybrid control strategy is proposed: PFM frequency modulation control is used from full load to light load. And from light load to no load, Burst control is used to adjust the output voltage to improve the efficiency of the converter in the full load range. Finally, a 100W prototype was designed for testing, and it was found that the efficiency of the hybrid control reached 81.6% when the converter was under very light load, which was 10.8% higher than the traditional PFM control. The experiment verifies the effectiveness and feasibility of the control method.