Zero Sequence Voltage and Current Control in Four-wire Grids-fed by Grid-forming Inverters  

作　　者：Zixian Zhu Wei Chen Vito Giuseppe Monopoli 

机构地区：[1]the College of Electrical And Information Engineering,Hunan University,Changsha,China [2]the College of Electrical and Information Engineering,Lanzhou University of Technology,Lanzhou,China [3]the Department of Electrical and Information Engineering,Bari Polytechnic,Bari,Italy

出　　处：《CSEE Journal of Power and Energy Systems》2023年第6期2272-2279,共8页中国电机工程学会电力与能源系统学报（英文）

基　　金：the National Natural Science Foundation of China(NSFC)under Grant 51767017;National Science and Technology Major Project of Gansu Province under Grant 19ZD2GA003.

摘　　要：Low voltage three-phase four-wire AC distribution grids may experience high neutral current,mainly caused by asymmetrical distribution of single-phase loads in three phases.High neutral current will not only increase line losses but also result in neutral potential variations.For the LV AC distribution grid established by a grid-forming inverter(e.g.,uninterruptible power supply and solid-state-transformer),it also suffers from the same neutral current issues.Therefore,this paper comparatively studies several neutral current control approaches and their impacts on grid voltage balance,which is required by grid code.Then,this paper proposes an optimal neutral current control approach,which can obtain maximum neutral current suppression with less impact on grid voltage balance.The correctness of the theoretical analysis is validated through both simulation and experimental results.

关 键 词：LV AC grid neutral current reduction grid-forming inverter three-phase four-wire system 

分 类 号：TM46[电气工程—电器] TM761.12