10 kV交直流配网弧光过电压特性分析  

Analysis of Arc Overvoltage Characteristics of 10 kV AC/DC Distribution Network

作　　者：李彦吉 付昱 李江[2] 容春艳 车晓涛 LI Yanji;FU Yu;LI Jiang;RONG Chunyan;CHE Xiaotao(State Grid HulunBuir Power Supply Company,HulunBuir,Inner Mongolia 021100,China;College of Electrical Engineering,Northeast Electric Power University,Jilin,Jilin 132012,China;Economic Technology Research Institute,State Grid Hebei Electric Power Co.,Ltd.,Shijiazhuang 050000,China;Luoyang Power Supply Company of State Grid Henan Electric Power Co.,Ltd.,Luoyang,Henan 471000,China)

机构地区：[1]国网呼伦贝尔供电公司,内蒙古呼伦贝尔021000 [2]东北电力大学电气工程学院,吉林吉林132012 [3]国网河北省电力有限公司经济技术研究院,石家庄050000 [4]国网河南省电力公司洛阳供电公司,河南洛阳471000

出　　处：《南方电网技术》2020年第3期10-16,共7页Southern Power System Technology

基　　金：国家自然科学基金(51977030);国网呼伦贝尔电力公司科技项目。

摘　　要：小电阻接地是提高交直流配电网保护灵敏性、降低过电压水平的有效手段。弧光接地过电压威胁设备绝缘,因而分析该问题对交直流配网安全运行具有重要价值。通过搭建交直流混合配网,在10 kV交流侧模拟发生配电网弧光过电压场景,研究了交直流电网过电压水平和故障穿越特性。首先基于PSCAD/EMTDC仿真软件搭建了柔性直流配网仿真模型,构建了弧光接地过电压数学模型;然后,仿真交直流混合配网系统发生故障后非故障相过电压故障响应曲线,分析了交流侧发生单相接地故障时,零序、负序分量造成的弧光过电压穿越特性;最后,通过对比分析不同接地电阻条件下交直流电网过电压数据获得了其变化规律,结果表明接地电阻为6Ω时对过电压的抑制效果最佳。Small resistance grounding is an effective means to improve the protection sensitivity of AC and DC distribution network and reduce the overvoltage level.Arcing grounding overvoltage threatens equipment insulation,so it is of great value to analyze this problem for the safe operation of AC and DC distribution network.In this paper,an AC/DC hybrid distribution network is built to simulate the arc overvoltage scenario of the distribution network on the 10 kV AC side,and the AC/DC power grid overvoltage levels and fault ride-through characteristics are studied.Firstly,based on PSCAD/EMTDC simulation software,a flexible DC distribution network simulation model and arc grounding overvoltage mathematical model are built.Then,the overvoltage fault response curves of the non-fault phase after the AC/DC hybrid distribution network system fails are simulated,and the arc overvoltage ride-through characteristics caused by zero-sequence and negative-sequence components when a single-phase ground fault occurs on the AC side are analyzed.By comparing and analyzing the overvoltage data of AC and DC power grids under different ground resistance conditions,the change rule is obtained.The results show that the effect of suppressing overvoltage is the best when the ground resistance is 6Ω.

关 键 词：交直流配电网 单相接地故障 过电压 PSCAD/EMTDC 

分 类 号：TM726[电气工程—电力系统及自动化]