10kV配电网中性点接地方式的优化研究  

Optimization Research on Neutral Grounding Mode of 10 kV Distribution Networks

作　　者：刘渝根[1] 王建南[2] 米宏伟[1] 马晋佩 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030 [2]国网浙江省电力公司宁波供电公司,宁波315010

出　　处：《高电压技术》2015年第10期3355-3362,共8页High Voltage Engineering

基　　金：国家创新研究群体基金(51021005)~~

摘　　要：针对某市10 k V配电网中性点运行方式存在的问题,提出一种结合中性点经电阻接地和经消弧线圈接地的优化改造方案。用ATP-EMTP建立10 k V配网单相接地故障仿真模型,在两种不同中性点接地方式下,模拟多种单相接地故障。理论分析及仿真实验表明,该新型接地方式可有效抑制单相接地时刻的瞬态过电压,当接地故障发生于架空线末端时,中性点、母线和故障点上的瞬态过电压降幅分别为34.7%、25.3%和18.5%;同时,该新型接地方式能够避免虚幻接地现象发生,并且在发生永久性单相接地故障时,可以通过切换并联电阻以实现准确的故障选线。该新型接中性点地方式对于配网安全可靠运行具有重要意义。In order to resolve the existing problems of neutral grounding of 10 kV distribution of a city, we proposed an optimization approach which combines the resistance grounding and resonant grounding. We built a single-phase fault simulation model of 10 kV distribution network by ATP-EMTP, and simulated a variety of single-phase fault under the two different neutral grounding systems. Theoretical analysis and simulation results show that this new neutral grounding mode can effectively suppress the transient overvoltage when single-phase fault occurs. When the ground fault occurs in the end of overhead line, the transient overvoltage of neutral point and bus bar and fault point will reduce by 34.7%, 25.3%, and 18.5% respectively. Meanwhile, the new neutral grounding mode can avoid the phenomenon of visional grounding, and also is able to select the fault line accurately by switching the resistors in parallel with arc-suppression coil when the permanent single-phase fault occurs, therefore,the mode is of great significance for safety and reliability of dis- tribution network.

关 键 词：中性点接地方式 消弧线圈 瞬态过电压 弧光接地 ATP-EMTP 故障选线 

分 类 号：TM862[电气工程—高电压与绝缘技术]