Contactless detection of multi-point grounding in CT secondary circuit

被引：0

作者：

Zhang, Jiamin ^{[1
]}

Yuan, Yubo ^{[1
]}

Bu, Qiangsheng ^{[1
]}

Song, Shuang ^{[1
]}

机构：

[1] State Grid Jiangsu Electric Power Research Institute Co., Ltd., Nanjing

来源：

Dianli Zidonghua Shebei/Electric Power Automation Equipment | 2014年 / 34卷 / 10期

关键词：

Current transformers; Electric grounding; Fault detection; Inductive currents; Magnetic fields; Relay protection; Secondary circuit;

D O I：

10.3969/j.issn.1006-6047.2014.10.021

中图分类号：

学科分类号：

摘要：

Since the multi-point grounding in the secondary circuit of CT(Current Transformer) may cause the misoperation of relay protections, a detection method without any contact is proposed for it, which exerts the varying magnetic field on the secondary-circuit of CT and detects the induced current. If multi-point grounding exists, the induced current will be detected in the neutral line between two grounding points, and the larger the current is, the more obviously the multi-point grounding exists. An auxiliary frequency criterion is proposed to prevent the misoperation of relay protections caused by the large inductive current. Experimental results verify the correctness of the proposed method.

引用

页码：128 / 132and149

共 14 条

[1] Zhang H., Zhang S., Analysis of a 500 kV main transformer differential protection malfunction , Power System Protection and Control, 38, 11, pp. 137-139, (2010)
[2] Guo R., Impact of current loop multipoint earth on transformer differential protection, Relay, 36, 7, pp. 80-82, (2008)
[3] Zhong C., Analysis of maloperation of line protection in Cuishan 110 kV hydro-substation, Relay, 36, 7, pp. 86-91, (2008)
[4] Deng W., Sun K., Zhou H., Et al., Analysis of an unusual system fault, Relay, 33, 23, pp. 68-72, (2005)
[5] Chen J., Analysis and treatment of a 220 kV transmission line relay misaction fault, Southern Power System Technology, 2, 1, pp. 67-70, (2008)
[6] Li Z., Xu Z., Analysis of grounding point for voltage transformer secondary circuit, Electric Power Automation Equipment, 30, 10, pp. 141-144, (2010)
[7] Zhang F., Li Y., Yuan L., Et al., Research on multiple earth in voltage transformer secondary circuit, Guangdong Electric Power, 21, 4, pp. 5-14, (2008)
[8] Yhang Z., Guo Q., Zhao H., Improvement of PT secondary circuit, Power System Protection and Control, 36, 22, pp. 111-113, (2008)
[9] Cheng X., Cheng F., Cheng J., The analysis about N600 uncorrent connecting leads, Journal of Electric Power, 20, 4, pp. 387-389, (2005)
[10] Zhao W., Gao C., Lin H., One-point grounding detection of PT secondary circuit and multi-grounding points searching method , Electric Power Automation Equipment, 30, 6, pp. 148-150, (2010)

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