区外故障导致变压器电流互感器饱和及差动保护误动问题研究  

Study on the CT saturation and mal-operation of the transformer current differential protection during external faults

作　　者：戚宣威 李露 黄晓明 王松 裘愉涛[3] 尹项根[4] 

机构地区：[1]国网浙江省电力公司电力科学研究院,浙江杭州310014 [2]长沙理工大学电气与信息工程学院,湖南长沙410076 [3]国网浙江省电力公司,浙江杭州310007 [4]强电磁工程与新技术国家重点实验室(华中科技大学),湖北武汉430074

出　　处：《电力系统保护与控制》2017年第20期44-51,共8页Power System Protection and Control

基　　金：国家电网公司总部科技项目"基于故障暂态分量时频特征的线路保护原理研究"(5211DS17002J)

摘　　要：2016年以来,电网接连发生多起区外故障期间变压器差动保护误动的事件,严重威胁电力系统的安全稳定运行与电能的可靠供应。从理论研究、数字仿真以及现场录波数据分析等层面围绕误动原因展开了深入研究,结果表明P类互感器在区外故障期间发生暂态饱和是导致保护误动的主要原因。在此基础上,分析论证了有关的互感器饱和识别方法,并探讨了互感器选型需要考虑的多种因素。该研究旨在引起相关专家学者对于互感器暂态饱和问题的关注,并为针对该问题的分析思路与应对方法提供参考与借鉴。Several cases of unusual mal-operation of the differential protection for transformer occurred in the power gird in 2016, threatening the stable operation of the power grid and the reliability of the power supply seriously. The mal-operation reason is researched in detail based on the mathematical analysis, the digital simulation and the field recorded fault data analysis. It is disclosed that the P-class CT transient saturation leads to the mal-operation. On this basis, this paper analyses the performance of the CT saturation method, and discusses the CT selection principles. This paper aims at attracting the attention on the problem of the CT saturation and proposing the reference of the analysis method and the countermeasure for this problem.

关 键 词：电流互感器 暂态饱和 差动保护 变压器 

分 类 号：TM452[电气工程—电器] TM774