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| Circulating Current Loop Bandwidth Expansion for Parallel Three-Phase PWM Converter Connection System |
| Zhang Xueguang, Chen Jiaming, Zhang Wenjie, Xu Dianguo |
| Harbin Institute of Technology Harbin 150001 China |
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Abstract The common dc-link dual parallel three-phase converter-system would produce circulating current. To suppress circulating current, a method to expand the bandwidth of zero-sequence current loop was proposed. Restrictions to the bandwidth of zero-sequence current loop caused by the difference in parameters between inverters and the time delayed by the control system were analyzed based on the model of parallel system. The restrictions caused by parameter difference as well as different converter operating state was eliminated with the zero vectors feed-forward strategy. Dual current sampling and dual PWM duty update method combined with the zero vectors feed-forward strategy was proposed to expand the zero-sequence current bandwidth effectively. This method has fast dynamic response and good performance of circulating current suppression, without increase in switching frequency. Both the validity of the theoretical analysis and the effectiveness of the control strategy was confirmed by experimental results.
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Received: 13 September 2013
Published: 20 October 2015
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[1] 郭小强, 邬伟扬, 漆汉宏. 电网电压畸变不平衡情况下三相光伏并网逆变器控制策略[J]. 中国电机工程学报, 2013, 33(3): 22-28. Guo Xiaoqiang, Wu Weiyang, Qi Hanhong．Control strategies of three-phase PV grid-connected inverter under distorted and unbalanced voltage conditions[J]. Proceedings of the CSEE, 2013, 33(3): 22-28.
[2] 张兴, 邵章平, 王付胜, 等. 三相三电平模块化光伏并网系统的零序环流抑制[J]. 中国电机工程学报, 2013, 33(9): 17-24. Zhang Xing, Shao Zhangping, Wang Fusheng, et al. Zero-sequence circulating current reduction for three-phase three-level modular photovoltaic grid-
connected systems[J]. Proceedings of the CSEE, 2013, 33(9): 17-24.
[3] Zhang Yu, Kang Yong, Chen Jian.The zero-sequence circulating currents between parallel three-phase inverters with three-pole transformers and reactors[C]. Twenty-First Annual IEEE Applied Power Electronics Conference & Exposition, 2006.
[4] Inzunza R, Sumiya T, Fujii Y, et al. Parallel connection of grid-connected LCL inverters for MW-scaled photovoltaic systems[C]. International Power Electronics Conference, 2010, 1988-1993.
[5] Zhang Yu, Kang Yong, Chen Jian. The zero-sequence circulating currents between parallel three-phase inverters with three-pole transformers and reactors[C]. Applied Power Electronics Conference and Exposition, 2006: 1709-1715.
[6] Bao Xianwen, Zhuo Fang, Liu Baoquan, et al. Suppressing switching frequency circulating current in parallel inverters with carrier phase-shifted SPWM technique[C]. IEEE International Symposium on Industrial Electronics, 2012: 555-559.
[7] Chen T P. Dual-modulator compensation technique for parallel inverters using space-vector modulation[J]. IEEE Transactions on Industrial Electronics, 2009, 56(8): 3004-3012.
[8] Chen T P. Zero-sequence circulating current reduction method for parallel HEPWM inverters between AC bus and DC bus[J]. IEEE Transactions on Industrial Electronics, 2012, 59(1): 290-300.
[9] 温春雪, 李建林, 朱晓光, 等. 基于交错断续空间矢量调制的并联PWM变流器控制策略[J]. 电工技术学报, 2009, 24(10): 71-80. Wen Chunxue, Li Jianlin, Zhu Xiaoguang, et al. Control strategy for parallel PWM converters with interleaved discontinuous space-vector modulation[J]. Transactions of China Electrotechnical Society, 2009, 24(10): 71-80.
[10] Ye Z, Boroyevich D, Choi J Y, et al. Control of circulating current in two parallel three-phase Boost rectifiers[J]. IEEE Transactions on Power Electronics, 2002, 17(5): 609-615. |
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2015, Vol. 30 
