Abstract：The traditional auto-transformer in distribution network suffers from problems such as heavy magnetic core and difficult voltage regulation. To overcome these problems, a three-phase AC-AC converter based on switched-capacitor (SC) and dual-Buck converter (DBC) is proposed in this paper. The topology adopts a two-stage power conversion structure with high step-down ratio, continuously adjustable voltage and easy modular expansion, which can meet the requirements of voltage level transformation in distribution network. Firstly, the structure and operation principle of the converter were presented in detail, and the flexible regulation of output voltage was realized through the design and application of two-stage power conversion and dead-zone-free control. Secondly, the output gain expression and the equivalent circuit model of the converter were derived, and a simple voltage closed-loop control strategy was designed. Then the design method of key parameters was given, and the characteristics of the converter were reflected clearly by comparing with several structures. Finally, a 3.5kW experimental prototype was built to verify the correctness and feasibility of the proposed topology.
王汝田, 李辉, 刘闯, 裴忠晨, 孔令国. 基于开关电容与双降压变换器的三相AC-AC变换器[J]. 电工技术学报, 2022, 37(20): 5241-5252.
Wang Rutian, Li Hui, Liu Chuang, Pei Zhongchen, Kong Lingguo. A Three-Phase AC-AC Converter Based on Switched-Capacitor and Dual-Buck Converter. Transactions of China Electrotechnical Society, 2022, 37(20): 5241-5252.
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