电流互感器两点接地引起的线路纵差保护动作分析  

The analysis of three-terminal line protection act trip caused by multiple earthing of CT

作　　者：刘慧斌 苗茂 

机构地区：[1]山西省黄河万家寨水务集团有限公司,太原030012

出　　处：《电气技术》2018年第1期114-116,共3页Electrical Engineering

摘　　要：电流互感器二次侧两点接地可能会为继电保护装置引入一个外接电源回路,是否产生电流取决于这两点间的电位差以及两接地点间的电阻值。本文以实际为例,分析探究一起线路纵差动保护因两点接地而误动事故,通过叙述前因后果,建立简单电路模型,对比事故波形,进而验证对事故原因的判断,为继电保护技术人员深入研究互感器两点接地问题提供实践支撑。A two-point earthing of CT secondary circuit could provide a complete circuit for a external power source.The current in this circuit depends on voltage and resistance between the two earthing points. Based on a trip event happened in Yellow River Diversion Project pump station, this article has given the back ground information, analysis and modeling, to testify the assumption of the cause of trip event. It would be a good example for field engineers to deepen their knowledge of multiple earthing.

关 键 词：CT两点接地 继电保护 地电位差 纵差保护 三端保护 

分 类 号：TM773[电气工程—电力系统及自动化]