高压交流电缆金属护套接地电流超标原因分析与处理  

Cause Analysis and Treatment of Excessive Circulating Current in Metal Sheaths of High Voltage AC Cable

作　　者：刘哲 张明灿 成洪刚 裴雪辰 李晓明 LIU Zhe;ZHANG Mingcan;CHENG Honggang;PEI Xuechen;LI Xiaoming(Power China Hebei Electric Power Engineering Co.,Ltd,Shijiazhuang 050031,China;State Grid Hebei Electric Power Co.,Ltd.Shijiazhuang Power Supply Branch,Shijiazhuang 050051,China)

机构地区：[1]中国电建集团河北省电力勘测设计研究院有限公司,河北石家庄050031 [2]国网河北省电力有限公司石家庄供电分公司,河北石家庄050051

出　　处：《河北电力技术》2022年第2期72-76,共5页Hebei Electric Power

摘　　要：电缆金属护套接地电流对高压电缆影响很大,电流过大会产生大量热量,造成电缆温度升高,减少线路的输送容量。另外,温度升高会造成外护套老化,甚至诱发电缆或附件热击穿,引起线路火灾等事故。本文首先利用环流数学模型,分析了影响环流大小的影响因素,利用ATP电磁暂态程序重点分析了串联电阻、电感,或改变接地电阻对环流数值的影响。对环流抑制方法进行了分析,说明了各自的应用范围,并给出了环流在在线监测系统评价中的策略改进办法。最后,根据某220kV电缆线路环流实测数据,对上述方法进行了验证。The cable metal sheaths circulating currentt has a great influence on the high voltage cable,which will generate a lot of heat,causing the cable temperature to rise,thereby reducing the capacity of the line.In addition,the increase in temperature may also cause the agingof jacket,and even induce thermal breakdown of cables or accessories,causing accidents such as line fires.Metal sheaths of 220kV high-voltage AC cable lines are usually grounded by cross-bonded,and normally only small capacitive and circulating current exist.In this paper,the mathematical model of circulating current is used to analyze the factors that affect the size of the circulating current,and the ATP electromagnetic transient program is used to analyze the effect of series resistance,inductance,or changing the grounding resistance on the value of the circulating current.The methods of circulation suppression are analyzed,their application scopes are explained,and the strategy improvement method of circulation in the online monitoring system evaluation is given.Finally,according to the measured data of a 220kV cable line circulating current,the above method is verified.

关 键 词：高压交流电缆 金属护套 感应电压 金属护套接地电流(环流) 交叉互联接地 ATP 

分 类 号：TM755[电气工程—电力系统及自动化]