Abstract：Due to soft-switching for switching devices, resonant converters are suitable for high-power applications. This paper proposes a resonant converter which is suitable for grid-connected renewable energy sources. The converter can achieve high voltage-gain using LC parallel resonant tank. It has the features such as zero-voltage-switching (ZVS) turn-on, nearly ZVS turn-off, and zero-current- switching (ZCS) turn-off of rectifier diode. In addition, compared with the conventional resonant converter, the switching frequency variation of the proposed resonant converter is smaller over the entire load range. The operation principle of the converter and the selection of the resonant parameters are presented in the paper. A 1kW prototype is built in the lab to verify the effectiveness of the converter.
[1] 温家良, 吴锐, 彭畅, 等. 直流电网在中国的应用前景分析[J]. 中国电机工程学报, 2012, 32(13): 7-12. Wen Jialiang, Wu Rui, Peng Chang, et al. Analysis of DC grid prospects in China[J]. Proceedings of the CSEE, 2012, 32(13): 7-12. [2] 徐殿国, 刘瑜超, 武健. 多端直流输电系统控制研究综述[J]. 电工技术学报, 2015, 30(17): 1-12. Xu Dianguo, Liu Yuchao, Wu Jian. Rewiew on control strategies of multi-terminal direct current transmission system[J]. Transactions of China Electro- technical Society, 2015, 30(17): 1-12. [3] 陈霞, 林卫星, 孙海顺, 等. 基于多端直流输电的风电并网技术[J]. 电工技术学报, 2011, 26(7): 60-67. Chen Xia, Lin Weixing, Sun Haishun, et a1. LCC- MTDC technology for wind farms integration[J]. Transactions of China Electrotechnical Society, 2011, 26(7): 60-67. [4] 李响, 韩民晓. 海上风电串联多端VSC-HVDC协调控制策略[J]. 电工技术学报, 2013, 28(5): 42-48. Li Xiang, Han Minxiao. A coordinated control strategy of series multi-terminal VSC-HVDC for offshore wind farm[J]. Transactions of China Electro- technical Society, 2013, 28(5): 42-48. [5] 汤广福, 罗湘, 魏晓光. 多端直流输电与直流电网技术[J]. 中国电机工程学报, 2013, 33(10): 8-17. Tang Guangfu, Luo Xiang, Wei Xiaoguang. Multi- terminal HVDC and DC-grid technology[J]. Pro- ceedings of the CSEE, 2013, 33(10): 8-17. [6] Zhan C, Smith C, Crane A, et al. DC transmission and distribution system for a large offshore wind farm[C]// IET AC and DC Power Transmission, 2010: 1-5. [7] Erickson R W, Maksimovic D. Fundamentals of power electronics[M]. MA: Kluwer Academic, 2001. [8] Denniston N, Massoud A, Ahmed S, et al. Multiple module high gain high voltage DC-DC transformers for offshore wind energy systems[J]. IEEE Transa- ctions on Industrial Electronics, 2011, 58(5): 1877- 1886. [9] Chen W, Huang A, Lukic S, et al. A comparison of medium voltage high power DC/DC converters with high step-up conversion ratio for offshore wind energy systems[C]//Proceedings of IEEE Energy Conversion Congress and Exposition (ECCE), 2011: 584-589. [10] Chen W, Huang A, Li C, et al. Analysis and comparison of medium voltage high power DC/DC converters for offshore wind energy systems[J]. IEEE Transactions on Power Electronics, 2013, 28(4): 2014-2023. [11] Max L. Design and control of a DC collection grid for a wind farm[D]. Göteborg: Chalmers University of Technology, 2009. [12] Zhou Y, Macpherson D E, Blewit W, et al. Com- parison of DC-DC converter topologies for offshore wind-farm application[C]//Proceedings of IET Power Electronics, Machines and Drives (PEMD), Bristol, 2012: 1-6. [13] Fan S, Ma W, Lim T C, et al. Design and control of a wind energy conversion system based on a resonant DC/DC converter[J]. IET Renewable Power Gener- ation, 2011, 7(3): 265-274. [14] Jovcic D. Step-up DC-DC converter for megawatt size applications[J]. IET Power Electronics, 2009, 2(6): 675-685. [15] 温家良, 王秀环, 李跃, 等. 一种用于新能源并网的谐振升降压装置及其实现方法: 中国, 201210338755.3[P]. 2015. [16] 温家良, 王秀环, 郭高鹏, 等. 一种用于新能源并网的谐振升压装置: 中国, 201210456865.X[P]. 2012. [17] Jabbari M, Farzanehfard H, Farhangi S. A new resonant step-up converter based on unibirectional switches[C]//Proceedings of IEEE EuroCon, 2009: 849-852.
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