Abstract:This paper proposes a novel hybrid control strategy of full bridge LLC resonant converter. The control strategy integrates the advantages of both variable frequency control and fixed frequency control. It can be easily implemented by using only one IC. Under this control strategy, full bridge LLC resonant converter can operate under both variable frequency mode and phase shift mode. All the switches can realize zero-voltage switching from nearly zero to full load without any auxiliary circuit, and the rectified diodes can achieve zero-current switching, so the voltage stress across them is only the output voltage. Moreover, the switching frequency range is relatively narrow, so the converter is very suitable for wide-input-voltage-range applications. The detail operation principles and characteristics of the converter are analyzed, and the implementation of the proposed hybrid control strategy is given and discussed. A prototype of 250-500V input, 3kW output is built to verify the effectiveness of the strategy.
李菊, 阮新波. 全桥LLC谐振变换器的混合式控制策略[J]. 电工技术学报, 2013, 28(4): 72-79.
Li Ju, Ruan Xinbo. Hybrid Control Strategy of Full Bridge LLC Converters. Transactions of China Electrotechnical Society, 2013, 28(4): 72-79.
[1] Jiang Z H. Power management of hybrid photovoltaic-fuel cell power systems[C]. Proceedings of IEEE Power Engineering Society General Meeting, 2006: 1-6. [2] Sathyan A, Anthony K, Al Hallaj S. Hybrid wind/PV/fuel cell generation system[C]. Proceedings of IEEE Vehicle Power and Propulsion Conference, 2005: 495-500. [3] Ruan X, Chen Z, Chen W. Zero-voltage-switching PWM hybrid full-bridge three-level converter[J]. IEEE Transactions on Power Electronics, 2005, 20(2): 395-404. [4] Ruan X, Li B. Zero-voltage and zero-current- switching PWM hybrid full-bridge three-level converter[J]. IEEE Transactions on Industrial Electronics, 2005, 52(1): 213-220. [5] Yang B. Topology investigation for front end DC/DC power conversion for distributed power system[D]. Blacksburg, Virgina Polytechnic Institute and State University, 2003. [6] Lu B. Investigation of high-density integrated solution for AC-DC conversion of a distributed power system[D]. Blacksburg, Virgina Polytechnic Institute and State University, 2006. [7] Liu Y. High efficiency optimization of LLC resonant converter for wide load range[D]. Blacksburg, Virgina Polytechnic Institute and State University, 2008. [8] Canales F, Barbosa P, Lee F C. A wide input voltage and load output variations fixed-frequency ZVS DC-DC LLC resonant converter[C]. Proceedings of IEEE Industry Applications Conference, 2003: 2306- 2313. [9] Jin K, Ruan X. Hybrid full-bridge three-level LLC resonant converter-a novel DC-DC converter suitable for fuel cell power system[J]. IEEE Power Electronics on Industrial Electronics, 2006, 53(5): 1492- 1503. [10] Chen Y, Kang Y. A fully regulated dual-output DC-DC converter with special-connected two transformers cell and complementary pulsewidth modulation-PFM[J]. IEEE Transactions on Power Electronics, 2010, 25(5): 1296-1309.