High Resistance Ground Fault Protection of Low Resistance Grounding System Based on Zero Sequence Current Projection Coefficient

被引：0

作者：

Yang F. ^{[1
]}

Liu X. ^{[2
]}

Shen Y. ^{[1
]}

Xue Y. ^{[2
]}

Zhou Z. ^{[1
]}

Xu B. ^{[3
]}

机构：

[1] State Grid Hubei Electric Power Research Institute, Wuhan, 430077, Hubei

[2] College of New Energy, China University of Petroleum (East China), Qingdao, 266580, Shandong

[3] Shandong Kehui Power Automation Co., Ltd., Zibo, 255087, Shandong

来源：

Dianwang Jishu/Power System Technology | 2020年 / 44卷 / 03期

基金：

中国国家自然科学基金;

关键词：

Ground fault protection; High impedance grounding; Low resistance grounding system; Projection; Single-phase grounding fault;

D O I：

10.13335/j.1000-3673.pst.2018.2644

中图分类号：

TM7 [输配电工程、电力网及电力系统];

学科分类号：

080802 ;

摘要：

Low-resistance grounding system can effectively suppress overvoltage and quickly remove faults. With the increasing scale of cable networks, more and more large and medium-sized cities begin to use this grounding mode. However, the currently used start-up threshold of zero-sequence over-current protection is high, and the protection would refuse to operate at high-resistance grounding fault. This paper analyzes the relationship between the zero-sequence currents on neutral point and on line during grounding fault. It is found that the zero-sequence current of faulty line is slightly larger than neutral zero-sequence current and they are approximately reversed to each other in phase position. The zero-sequence current in healthy line is much smaller than the neutral zero-sequence current, and their phase difference is about 90°. A grounding fault protection method using the zero-sequence current projection coefficient of the line on neutral point is proposed, to significantly improve sensitivity of protection in high-resistance grounding fault. Simulation results verify correctness and effectiveness of the proposed method. © 2020, Power System Technology Press. All right reserved.

引用

页码：1128 / 1133

页数：5

共 19 条

[1] Cao M., Yao H., On neutral grounding modes of cable network, Power System Technology, 27, 2, pp. 84-89, (2003)
[2] Gan Y., Tang Q., Fang Q., Et al., Analysis of low-resistance neutral grounding in urban medium-voltage power grid, Proceedings of the CSU-EPSA, 25, 3, pp. 138-141, (2013)
[3] Guo L., Xue Y., Xu B., Et al., Research on effects of neutral grounding modes on power supply reliability in distribution networks, Power System Technology, 39, 8, pp. 2340-2345, (2015)
[4] Luo L., Xiang B., Xu J., Et al., Simulation and test of step voltage caused by single-phase grounding fault of 10 kV system earthed with low resistance, Electric Power Automation Equipment, 33, 6, pp. 21-26, (2013)
[5] Yu L., Guo X., Han B., Et al., Principle of adaptive zero-sequence current protection and implementation of its device for feeder of low resistance grounding system, Electric Power Automation Equipment, 37, 11, pp. 125-131, (2017)
[6] Ma L., Wang J., Effect of low-resistance connection to urban distribution network, Electric Power Automation Equipment, 32, 4, pp. 138-141, (2012)
[7] Liu Y., Cai Y., Deng G., Et al., Operation and protection in distribution system with small resistance grounding mode, Distribution & Utilization, 32, 6, pp. 30-35, (2015)
[8] Xue Y., Liu S., Wang Y., Et al., Grounding gault protection in low resistance grounding system based on zero-sequence voltage ratio restrain, Automation of Electric Power Systems, 40, 16, pp. 112-117, (2016)
[9] Lin Z., Liu X., Wang Y., Et al., Grounding fault protection based on zero sequence current comparison in low resistance grounding system, Power System Protection and Control, 46, 22, pp. 21-27, (2018)
[10] Geng J., Wang B., Dong X., Et al., Analysis and detection of high impedance grounding fault in neutral point effectively grounding distribution network, Automation of Electric Power Systems, 37, 16, pp. 85-91, (2013)

← 1 2 →