Abstract：To satisfy the need of the high input voltage in three-phase grid-connected photovoltaic (PV) inverter, overcome the shortage of power frequency isolation transformer severe material consumes. An improved boost-voltage phase-shifted full-bridge soft switching converter is presented. It has two step-up windings rectifiers in series and one step-down winding in series with a linear reactor. The former is used to increase the output voltage; the latter is used to ensure the devices soft switching in the full power scope. Firstly, its principle is analyzed with detail. Secondly, an asymmetrical digital phase-shift pulse width modulation (PWM) control scheme and the implement method are given. The last, the control software is designed, and a prototype is completed. Experimental results show that the control scheme is feasible, the converter has high efficiency.
[1] Carrasco J M, Franquelo L G, Bialasiewicz J T, et al. Power-electronics systems for the grid integration of renewable energy sources: a survey[J]. IEEE Transactions on Industrial Electronics, 2006, 53(4): 1002-1016. [2] Trishan Esram, Patrick L Chapman. Comparison of photovoltaic array maximum power point tracking techniques[J]. IEEE Transactions on Energy Conversion, 2007, 22(2): 439-449. [3] 丁新平, 卢燕, 钱照明, 等. Z源逆变器光伏并网系统光伏电池MPPT和逆变器并网的单级控制[J]. 电工技术学报, 2010, 25(4): 122-128. Ding Xinping, Lu Yan, Qian Zhaoming, et al. Single-stage control of MPPT and grid-connected on Z-source inverter PV system[J]. Transactions of China Electrotechnical Society, 2010, 25(4): 122-128. [4] 张兴, 孙龙林, 许颇, 等. 单相非隔离型光伏并网系统中共模电流抑制研究[J]. 太阳能学报, 2009, 36(9): 1202-1207. Zhang Xing, Sun Longlin, Xu Po, et. al. Research on common-mode current reduction of nonisolated single-phase grid-connected photovoltaic systems[J]. Acta Energiae Solaris Sinica, 2009, 36(9): 1202-1207. [5] 肖华锋, 谢少军. 用于光伏并网的交错型双管Buck-Boost变换器[J]. 中国电机工程学报, 2010, 30(21): 7-12. Xiao Huafeng, Xie Shaojun. An interleaving double-switch buck-boost converter for PV grid-connected inverter[J]. Proceedings of the CSEE. 2010, 30(21): 7-12. [6] Song T T, Huang N C, Ioinovici A. A family of zero-voltage and zero-current-switching(ZVZCS) three-level DC-DC converter the secondary-assisted regenerative passive snubber[J]. IEEE Transactions on Circuits and Systems, 2005, 52(11): 2473-2481. [7] 姜雪松, 温旭辉, 许海平. 燃料电池电动车用隔离Boost全桥变换器的研究[J]. 南京航空航天大学学报, 2006, 38(1): 64-69. Jiang Xuesong, Wen Xuhui, Xu Haiping. Isolated boost full bridge converter for fuel cell electric vehicle[J]. Journal of Nanjing University of Aeronautics & Astronautics, 2006, 38(1): 64-69. [8] 阮新波, 严仰光. 脉宽调制DC-DC全桥变换器的软开关技术[M]. 北京: 科学出版社, 2001. [9] 李传文. 光伏升压全桥软开关DC-DC变换器的研制[D], 济南: 山东大学, 2008. [10] 杨通, 黄延龄, 张光先. 数字化的逆变弧焊电源[J]. 电焊机, 2009, 39(2): 11-17. Yang Tong, Huang Yanling, Zhang Guangxian. Digitalized arc welding power[J]. Electric Welding Machine, 2009, 39(2): 11-17. [11] 赵振民, 岳云涛. 一种基于UC3879控制的全桥软开关DC/DC变换器[J]. 电力电子技术, 2005, 39(3): 107-110. Zhao Zhenmin, Yue Yuntao. Research on a soft switching DC/DC full-bridge converters based on UC3879 controller[J]. Power Electronics, 2005, 39(3): 107-110. [12] 苏奎峰, 吕强. TMS320F2812原理与开发[M]. 北京: 电子工业出版社, 2005. [13] Kim E S, Kim T J, Byun Y B, et al. High power full-bridge DC/DC converter using digital-to-phase- shift PWM circuit[J]. Institute of Electrical and Electronics Engineers Inc., 2001, 1: 221-225. [14] Kim E S, Kim T J, Byun Y B, et al. High power full bridge DC/DC convener using digital-to-phase-shift PWM circuit[C]. Proceedings of the IEEE PESC, 2001: 221-225. [15] 谢永刚. 移相全桥AVZCS变换器及数字化控制研究[D]. 武汉：华中科技大学, 2002.
2011, Vol. 26 
