Robust Control and Circulating Current Analysis for Grid-Connected Parallel Inverters
Fang Hongwei1, Tao Yue1, Xiao Zhaoxia2, He Yejun1
1. School of Electrical Engineering & Automation Tianjin University Tianjin 300072 China; 2. Tianjin Key Laboratory of Advanced Technology of Electrical Engineering and Energy Tianjin Polytechnic University Tianjin 300387 China
Abstract：A robust control strategy for the grid-connected parallel inverters is developed in this paper. Based on the analysis of the circuit structure and circulating current of the parallel system, a simple single leg control method is proposed. Structured singular value μ synthesis based on H∞ control theory is applied, to decrease the impacts from various uncertainties as well as improve the stability and performance of the parallel system. As a result, the accurate current control and circulating current restraining are realized. Further, the range of the uncertainty is given for stable operation of the system, while the controller can ensure the stability in the determined range. The simulation and experimental results show the effectiveness of the proposed control scheme.
方红伟, 陶月, 肖朝霞, 贺叶君. 并网逆变器并联系统的鲁棒控制与环流分析[J]. 电工技术学报, 2017, 32(18): 248-258.
Fang Hongwei, Tao Yue, Xiao Zhaoxia, He Yejun. Robust Control and Circulating Current Analysis for Grid-Connected Parallel Inverters. Transactions of China Electrotechnical Society, 2017, 32(18): 248-258.
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2017, Vol. 32 
