An Improved Buck PFC Converter With High Power Factor

• Published in: IEEE transactions on power electronics Vol. 28; no. 5; pp. 2277 - 2284
• Main Authors: Xie, Xiaogao, Zhao, Chen, Zheng, Lingwei, Liu, Shirong
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.05.2013; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: AC-DC; Applied sciences; buck power factor correction (PFC); Circuit properties; class C; Convertors; Diodes; Electric, optical and optoelectronic circuits; Electrical engineering. Electrical power engineering; Electrical machines; Electronic circuits; Electronics; Equivalent circuits; Exact sciences and technology; Harmonic analysis; high efficiency; high power factor (PF); Inductors; Power electronics, power supplies; Power supply; Prototypes; Reactive power; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Signal convertors; Switches; Topology; Voltage control; Performance evaluation; high power factor (PF); Power converter; Prototype; Power system harmonics; Power system stability; Optimal design; Control unit; Power factor regulation; Energy quality; Harmonic distortion; Power factor; Inward current; buck power factor correction (PFC); Alternating current; Class C; Power factor correction; Dead zone; Power electronics; Topology; Standards; Step down convertor; High power; Optimal control; high efficiency; AC-DC; Switching diode; Service quality; Comparative study; Control code
• ISSN: 0885-8993; 1941-0107
• DOI: 10.1109/TPEL.2012.2214060

An improved buck power factor correction (PFC) converter topology is proposed in this paper. By adding an auxiliary switch and two diodes, the dead zones in ac input current of traditional buck PFC converter can be eliminated. An improved constant ON-time control is proposed and utilized in this improved buck PFC converter to force it that operates in critical conduction mode (CRM). With optimal control parameters, nearly unit power factor can be achieved and the input current harmonics can meet the IEC61000-3-2 class C standard within the universal input voltage range. Moreover, the efficiency of the proposed converter is not deteriorated compared to the conventional buck converter. Detailed theoretical analysis and optimal design considerations for the proposed converter are presented and verified by a 100-W lab-made prototype.