摘要
为了提高中小面积变电站接地性能,基于CDEGS接地仿真软件,结合工程实例,对应用环形帽檐式均压带改善某110 kV变电站地网接地性能进行了研究。分析表明,在主地网外围布置“1~1.5 m”的环形帽檐式均压带后,接地电阻下降12.6%,网外最大接触电压和最大跨步电压分别下降25.2%和31.2%,而网内下降程度分别为39.6%和34.5%,短路最大地表电位升超过2000 V但低于5000 V,最大跨步电压满足安全限值,但对于可能存在接触电压的站址地面需要铺设砾石以提高安全限值。进一步研究表明,环形帽檐式均压带埋深过大不利于均压,埋深过小则起不到很好的降阻效果,实际应用需综合接地安全性和施工难度来合理选择埋深;两级均压带与主地网之间可采用接续连接方式,以降低施工复杂性和减少耗材。
In order to improve the grounding performance of small and medium-sized substations,based on the CDEGS software,combined with engineering examples,the application of a ring-shaped bongrace type uniform voltage band to improve the grounding performance of a 110 kV substation is studied.The analysis shows that after the“1~1.5 m”ring-shaped bongrace type uniform voltage band is arranged on the periphery of the main grounding grid,the grounding resistance drops by 12.6%,the maximum touch voltage and the maximum step voltage outside the grid drop by 25.2%and 31.2%,while in the grid those decrease is 39.6%and 34.5%respectively.The maximum ground potential rise exceeds 2000 V but is lower than 5000 V.The maximum step voltage meets the safety limit.However,gravel must be laid on the ground of the site where touch voltage may exceed the safety limit.Further research shows that too large buried depth of the ring-shaped bongrace type uniform voltage band is not conducive to potential equalization,and too small burial depth will not achieve a good resistance reduction effect.Actual application needs to integrate grounding safety and construction difficulty to select a reasonable buried depth;The two-stage uniform voltage band can be connected to the main ground grid in sequence,which reduce construction complexity and material consumption.
作者
李凡
严雪莹
朱奕弢
赵崇娟
黄焕
蔡力
LI Fan;YAN Xueying;ZHU Yitao;ZHAO Chongjuan;HUANG Huan;CAI Li(Huzhou Electric Power Design Institute Co.,Ltd.,Huzhou 31300,China;Wuhan University,Wuhan 430072,China)
出处
《电瓷避雷器》
CAS
北大核心
2023年第1期133-139,147,共8页
Insulators and Surge Arresters
关键词
环形帽檐式均压带
接地网
接地性能
埋深
连接方式
ring-shaped bongrace type uniform voltage band
grounding grid
grounding performance
buried depth
connection method
