An High Precision Autonomous Current Sharing Control Strategy without High Bandwidth Communication Line
Zhi Na1, Ding Ke1, Huang Qinghui2, Li Wuhua2, Zhang Hui1
1. School of Automation and Information Engineering Xi'an University of Technology College Xi'an 710048 China; 2. School of Electrical Engineering Zhejiang University Hangzhou 310000 China
Abstract：The DC microgrid parallel systems mostly use droop control to achieve power distribution. However, the line impedance will reduce power distribution precision. The traditional current sharing strategy is based on high-bandwidth communication lines, which has high manufacturing cost and low reliability. In addition, the communication delay in the communication line will affect the power distribution precision. In this paper, an optical autonomous current sharing strategy of parallel storage converters in the DC microgrid is proposed. This strategy analyzes the influence of line impedance on the power distribution characteristics of the converter in constant voltage operation mode and droop operation mode. A virtual impedance compensation link is designed to adjust the output power of the converter according to the output electrical characteristics of the converter, and then, the output power of each converter is equally shared. The effectiveness of the proposed parallel system autonomous current sharing strategy is verified by simulation and experiment.
支娜, 丁可, 黄庆辉, 李武华, 张辉. 一种无需高带宽通信线路的高精度自主均流控制策略[J]. 电工技术学报, 2021, 36(16): 3375-3385.
Zhi Na, Ding Ke, Huang Qinghui, Li Wuhua, Zhang Hui. An High Precision Autonomous Current Sharing Control Strategy without High Bandwidth Communication Line. Transactions of China Electrotechnical Society, 2021, 36(16): 3375-3385.
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2021, Vol. 36 
