应用于直流电网的新型直流自耦变压器  

A Novel DC Autotransformer Applied to DC Grids

作　　者：张颖[1] 荆龙[1] 吴学智 武文[1] 魏梦航 ZHANG Ying;JING Long;WU Xuezhi;WU Wen;WEI Menghang(National Active Distribution Network Technology Research Center(NANTEC)(Beijing Jiaotong University),Haidian District,Beijing 100044,China;Collaborative Innovation Center of Electric Vehicles in Beijing,Haidian District,Beijing 100044,China)

机构地区：[1]国家能源主动配电网技术研发中心(北京交通大学),北京市海淀区100044 [2]北京电动车辆协同创新中心,北京市海淀区100044

出　　处：《电网技术》2019年第9期3297-3304,共8页Power System Technology

基　　金：国家重点研发计划项目(2016YFB0900500)~~

摘　　要：为了满足直流电网对直流变压器高效率、低成本的迫切需求,改进传统直流变压器设计容量大、效率低的不足,研究了一种基于改进的双向隔离型DC/DC变换器串并联结构的新型直流自耦变压器(DC AUTO)拓扑,只有部分功率经过变压器传输,可部分降低变压器的容量和设计成本,可依据两侧直流系统的电压等级灵活地对子模块进行串并联组合。采用交错并联控制减小了子模块的滤波电感和电容值从而降低了子模块体体积和成本。为了确保系统稳定运行,采用电容电压均衡控制和平均控制实现系统均压及均流。根据两侧是有源或无源特性提出2种整体控制策略。最后,对所提出的拓扑和控制策略进行仿真分析和实验验证。In order to meet the urgent demand of efficient and low-cost DC transformers for DC grid and overcome the deficiency of traditional DC transformers with large power capacity and low efficiency,this paper proposed a new topology of DC autotransformer(DC AUTO)based on the series and parallel structure of an improved bidirectional isolated DC/DC converter.Only partial power was transmitted through the transformer,thus partly reducing power capacity and design cost.The sub-modules(SM)could be flexibly connected in series and parallel according to the voltage levels of the DC systems on both sides.Interleaved parallel control could reduce filter inductance and capacitance of the sub-modules,thereby reducing their volume and cost.In order to ensure stable operation of the system,capacitor voltage balance control and average control were applied to achieve voltage and current sharing.Then two overall control strategies were proposed based on whether the two sides were active or passive.Finally,the proposed topology and control strategies were simulated in MATLAB and verified experimentally.

关 键 词：直流电网 直流变压器 直流自耦变压器 双向DC/DC变换器 交错并联 

分 类 号：TM721[电气工程—电力系统及自动化]