Abstract：Based on the analysis to the structure and features of the cascaded H-Bridge (CHB) rectifier(CHBR) stage of transformerless high power converters, the concept of making CHBR working on optimum point and the corresponding novel modulation method are proposed by this paper. The optimum working point in safety operation area is firstly discussed, and then the principle of fast balancing DC-link capacitor voltages for each cell of CHBR with the novel modulation method is explained in detail, and the quantitative description for the allowed maximum unbalanced loads is also presented. Moreover, the implementation of the proposed novel modulation method which chooses two different modulation curves based on two-dimensional modulation by signs between AC-side output voltage and inductance current is illustrated as well. Finally, experiment results from the prototype test are given, which verified the validity of the proposed novel modulation method.
王聪, 张国澎, 王俊, 蔡莹莹. 一种适用于级联H桥整流直流侧电容电压快速平衡的新型调制方法[J]. 电工技术学报, 2013, 28(8): 120-127.
Wang Cong, Zhang Guopeng, Wang Jun, Cai Yingying. A Novel Modulation Method for Fast Balancing DC-Link Capacitor Voltages of Cascaded H-Bridge Rectifier. Transactions of China Electrotechnical Society, 2013, 28(8): 120-127.
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2013, Vol. 28 
