基于开关电容与双降压变换器的三相AC-AC变换器  

A Three-Phase AC-AC Converter Based on Switched-Capacitor and Dual-Buck Converter

作　　者：王汝田[1] 李辉[1] 刘闯[1] 裴忠晨 孔令国[1] Wang Rutian;Li Hui;Liu Chuang;Pei Zhongchen;Kong Lingguo(School of Electrical Engineering Northeast Electric Power University,Jilin 132012 China)

机构地区：[1]东北电力大学电气工程学院,吉林132012

出　　处：《电工技术学报》2022年第20期5241-5252,共12页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(51877035)。

摘　　要：针对配电网中传统自耦变压器铁心体积大、电压调控难等问题,该文提出一种基于开关电容(SC)与双降压变换器(DBC)的三相AC-AC变换器进行替代。该拓扑采用双级式功率变换结构,具有高降压比、电压连续可调、易于模块化拓展等特性,能够满足配电网电压变换需求。首先,详细介绍所提变换器的拓扑结构及工作原理,通过双级式功率变换与无死区控制的设计与应用,实现输出电压柔性调节;其次,推导三相AC-AC变换器输出增益表达式与等效电路模型并设计简单的电压闭环控制策略,探讨三相AC-AC变换器关键参数设计方法,通过与几种结构对比清晰地反映变换器特点;最后,搭建一台3.5kW实验样机,验证了所提拓扑结构的正确性和可行性。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.

关 键 词：配电网 开关电容 双降压变换器 三相 交-交变换器 

分 类 号：TM46[电气工程—电器]