单向推挽式直流自耦变压器拓扑及其控制策略  

Topology and control strategy of unidirectional push⁃pull DC auto⁃transformer

作　　者：胡隽璇 曾智桢 韩鸣宇 刘峪涵 汪星耀 周友维 左文平[2] HU Jun-xuan;ZENG Zhi-zhen;HAN Ming-yu;LIU Yu-han;WANG Xing-yao;ZHOU You-wei;ZUO Wen-ping(Power China Zhongnan Engineering Co.,Ltd.,Changsha 410014,China;State Key Laboratory of Advanced Electromagnetic Engineering and Technology(Huazhong University of Science and Technology),Wuhan 430074,China)

机构地区：[1]中国电建集团中南勘测设计研究院有限公司,湖南长沙410014 [2]强电磁工程与新技术国家重点实验室(华中科技大学),湖北武汉430074

出　　处：《电工电能新技术》2022年第8期10-19,共10页Advanced Technology of Electrical Engineering and Energy

基　　金：国家自然科学基金项目(52007076)。

摘　　要：基于推挽式直流自耦变压器(PPDAT),本文提出了一种新型单向直流变压器,根据功率传输方向,可划分为升压型PPDAT(UU-PPDAT)与降压型PPDAT(DU-PPDAT)两类单向直流自耦变压器拓扑。首先,介绍了UU-PPDAT与DU-PPDAT的拓扑与工作原理,两类拓扑中都包含桥臂(串联半桥子模块)、四绕组变压器与全波整流电路。基于四绕组变压器的特定属性与桥臂输出电压控制,UU-PPDAT与DU-PPDAT能够实现对各绕组两端电压的精准控制,进而控制全波整流电路对电容的充电功率,维持互联直流系统间功率的正常传输。其次,设计了适用于UU-PPDAT与DU-PPDAT的通用型控制策略,基于功率传输要求得到桥臂输出电压交流分量,结合桥臂输出电压直流分量与阀级控制,得到桥臂中串联子模块开关信号。最后,基于PSCAD/EMTDC仿真验证了单向PPDAT拓扑及其控制策略的可行性与有效性。Based on push⁃pull DC auto⁃transformer(PPDAT),this paper proposes a new unidirectional DC trans⁃former.According to the power transmission direction,it can be divided into two types of unidirectional DC auto⁃transformer topologies,step⁃up unidirectional PPDAT(UU⁃PPDAT)and step⁃down unidirectional PPDAT(DU⁃PP⁃DAT).Firstly,the topology and working principle of UU⁃PPDAT and DU⁃PPDAT are introduced.UU⁃PPDAT and DU⁃PPDAT both include bridge arms(series half⁃bridge sub⁃modules),four⁃winding transformer and full⁃wave rectifying circuit.Based on the four⁃winding transformer and the output voltage control of the bridge arms,UU⁃PP⁃DAT and DU⁃PPDAT can achieve precise control of the voltage across the windings,thereby controlling the char⁃ging power of the full⁃wave rectifying circuit to the capacitor,and maintaining the stable operation of the system.Secondly,a general control strategy suitable for UU⁃PPDAT and DU⁃PPDAT is designed.Based on the power trans⁃mission requirements,the AC component of the output voltage of the bridge arms is obtained.Combining the DC component of the output voltage of the bridge arms and valve⁃level control,the switch signals of series sub⁃module in the bridge arms are obtained.Finally,based on PSCAD/EMTDC,the feasibility and effectiveness of unidirec⁃tional PPDAT topology and its control strategy are verified.

关 键 词：高压直流输电 直流电网 自耦变压器 推挽式直流自耦变压器 单向推挽式直流自耦变压器 

分 类 号：TM721.1[电气工程—电力系统及自动化]