|
|
|
| Analysis of an event of maloperation of zero-sequence protection for 10kV grounding transformer |
| ZHENG Yu, JIANG Jiongfeng |
| Guangdong Power Grid Co., Ltd, Zhongshan Power Supply Bureau, Zhongshan, Guangdong 528400 |
|
|
|
|
Abstract This paper analyzes an accident of voltage loss of a section of 10kV bus in 110kV A substation due to misoperation of grounding transformer protection. It is found that the current transformer (CT) configuration of grounding transformer zero sequence is unreasonable in the process of 10kV system neutral point reconstruction, and a solution is proposed to install the zero-sequence protection CT on the high side of the grounding transformer at the small resistance of grounding transformer neutral point. This method can ensure that the grounding transformer protection will not act wrongly when the arc suppression coil is compensated and before the small resistance is input, which improves the power supply reliability of the power grid. This is of practical significance to the reconstruction project of 10kV system neutral point grounded by small resistance in parallel with arc suppression coil.
|
|
Received: 30 June 2020
|
|
|
|
| Cite this article: |
|
ZHENG Yu,JIANG Jiongfeng. Analysis of an event of maloperation of zero-sequence protection for 10kV grounding transformer[J]. Electrical Engineering, 2021, 22(2): 101-104.
|
|
|
|
| URL: |
|
http://dqjs.cesmedia.cn/EN/Y2021/V22/I2/101
|
[1] 江清楷, 何欣欣. 10kV可控电阻接地系统接地变零序电流保护若干问题的分析[J]. 电气技术, 2019, 20(9): 120-122.
[2] 李谦, 赵东生, 肖磊石, 等. 广东电网小电流接地系统中性点接地方式优化对策[J]. 广东电力, 2017, 30(12): 124-129.
[3] 黄志方, 魏立新, 李刚. 消弧线圈并联小电阻的灵活接地方式[J]. 广东电力, 2014, 27(6): 64-67.
[4] 李锦图. 10kV配电网中性点经消弧线圈并联电阻接地特性分析[D]. 广州: 华南理工大学, 2019.
[5] 朱孝军, 谭志聪, 莫颖生. 探讨消弧线圈瞬时并联选线电阻的接地方式[J]. 广东电力, 2009, 22(8): 33-36.
[6] 韩静, 徐丽杰. 中性点经消弧线圈瞬时并联小电阻接地分析[J]. 高电压技术, 2005, 31(1): 38-39.
[7] 吴少钿. 一起接地变兼站用变保护误动的事故调查分析[J]. 河南科技, 2013(4): 50.
[8] 邵彬. 一起35kV接地变越级跳闸事故分析[J]. 安全生产, 2019(7): 53-55.
[9] 廖文彪, 廖媚媚, 叶健, 等. 一起接地变保护误动作事件的原因分析及整改措施[J]. 黑龙江电力, 2019, 41(5): 433-436.
[10] 刘雪霞. 10kV配电网小电阻接地零序保护的可靠性分析[D]. 徐州: 中国矿业大学, 2019. |
|
|
|
2021, Vol. 22 
