Abstract：Aimed at the drawbacks of complicated three-dimensional model and neutral point potential drifting in three-level three-phase four-leg inverters, a novel strategy is proposed in this paper. It keeps neutral point potential balanced by descending dimension, analyzes the influence of each switching states on the neutral point potential, and optimizes switching states based on space vector modulation. The average current flowing through the neutral point of DC capacitors is absolutely zero during each sampling period, and hence the neutral point potential is balanced effectively. The simulation and experimental results verify that the proposed strategy can eliminate the neutral point potential drifting with modulation ratio and load conditions over a big range.
朱婷婷, 邓智泉, 王晓琳, 王宇. 一种三电平三相四桥臂逆变器中点电位平衡策略[J]. 电工技术学报, 2012, 27(6): 77-82.
Zhu Tingting, Deng Zhiquan, Wang Xiaolin, Wang Yu. A Novel Strategy of Neutral Point Potential Balancing for Three-Level Three-Phase Four-leg Inverters. Transactions of China Electrotechnical Society, 2012, 27(6): 77-82.
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2012, Vol. 27 
