|
|
|
| Analysis of Power Frequency Electrical Quantity and Line Selection Applicability for Two-Point Grounding Faults Occurring on Different Phases in Isolated Neutral System |
| Qi Zhibin1, Tian Junyang2, Xue Yongduan1, Cai Zhuoyuan1, Xu Bingyin3 |
1. New Energy College China University of Petroleum (East China) Qingdao 266580 China;
2. Guangxi Power Grid Power Dispatching Control Center Nanning 530023 China;
3. Research Center for Smart Grid Shandong University of Technology Zibo 255049 China |
|
|
|
Abstract In isolated neutral system, when two-point grounding faults occurring on different phases take place and at least one of the transition resistances is large, the outgoing protection with the small fault current can not be directly removed, it still need to rely on the line selection device to achieve protection. At present, there are some problems in the research on the two-point grounding fault of the small current grounding system, such as lack of quantitative analysis, lack of line selection effect analysis, and difficult to be applied in practice et al. To address these issues, based on the fault equivalent circuit, this paper analyzes the power frequency fault characteristics for two-point grounding faults occurring on different phases in isolated neutral system. Based on the fault characteristics, the adaptability of the existing power frequency line selection methods to the two-point grounding fault of the different phase is analyzed and the development suggestion of line selection technology is put forward.
Firstly, Setting up the compound sequence network of two-point grounding faults occurring on different phases, using the nodal impedance matrixes to respectively deduce the expressions of power frequency components, such as two grounding fault point currents, zero-sequence voltage, and so on. Secondly, analyze the characteristics of two-point grounding fault power frequency electrical quantity with the change of the transition resistances in ungrounded systems and compare them with the characteristics of single-point grounding faults. Finally, according to the fault characteristics, the limitation of the existing line selection methods are analyzed, and the development ideas of two-point grounding fault line selection technology are put forward.
The results show that, when the transition resistance of at least one fault point is large, the amplitudes of zero-sequence voltage and zero-sequence current of power frequency in two-point grounding of the different phase show the characteristics of single-point grounding. At least one fault feeder has a power frequency zero-sequence current amplitude greater than that of the healthy feeder. The phase relationship of zero-sequence current of power frequency between the fault feeder and health feeder depends on two fault phase sequences, transition resistance of two fault points and total capacitance to the ground of the system. Generally, there is no definite phase relationship. In general, the zero-sequence voltage amplitude when two fault points are grounded is between the zero-sequence voltage when two fault points are grounded separately. When the transition resistance of two fault points is similar, the zero-sequence voltage when two fault points are grounded is minimum. For two-point grounding faults occurring on different phases in isolated neutral system, the zero-sequence voltage starting criterion still has high resistance to transition resistance and can reach the threshold value in most cases.
The zero-sequence current at the outlet of two fault lines generally does not conform to the characteristics of both fault feeder and healthy feeder, and the existing line selection principle is not fully applicable. When the amplitude and phase information are used for line selection, missing selection or rejection will occur.
Development suggestions of line selection technology: (1) As for the development of steady-state line selection technology for two-point grounding fault, based on the conclusions of power frequency characteristics, the change of power frequency characteristics of faulty line and non-faulty line before and after subsequent fault, or the change of power frequency characteristics of faulty line and non-faulty line before and after first fault line removal can be further studied. According to the difference of power frequency characteristics between fault line and non-fault line in two stages, two-point grounding fault detection is realized and the detection time is further shortened to improve detection efficiency. (2) As for the development of transient line selection technology for two-point grounding fault, based on the conclusions of power frequency characteristics, the intermittent arc grounding process after subsequent fault can be analyzed.
|
|
Received: 01 April 2022
|
|
|
|
|
|
[1] 徐丙垠, 李天友, 薛永端. 配电网继电保护与自动化[M]. 北京: 中国电力出版社, 2017.
[2] 徐丙垠, 薛永端, 冯光, 等. 配电网接地故障保护若干问题的探讨[J]. 电力系统自动化, 2019, 43(20): 1-7.
Xu Bingyin, Xue Yongduan, Feng Guang, et al.Discussion on several problems of earthing fault protection in distribution network[J]. Automation of Electric Power Systems, 2019, 43(20): 1-7.
[3] Topolanek D, Toman P, Ptacek M, et al.Evaluation of different solutions of faulted phase earthing technique for an earth fault current limitation[J]. CIRED - Open Access Proceedings Journal, 2017, 2017(1): 1107-1111.
[4] 王建元, 朱永涛, 秦思远. 基于方向行波能量的小电流接地系统故障选线方法[J]. 电工技术学报, 2021, 36(19): 4085-4096.
Wang Jianyuan, Zhu Yongtao, Qin Siyuan.Fault line selection method for small current grounding system based on directional traveling wave energy[J]. Transactions of China Electrotechnical Society, 2021, 36(19): 4085-4096.
[5] 秦苏亚, 薛永端, 刘砾钲, 等. 有源配电网小电流接地故障暂态特征及其影响分析[J]. 电工技术学报, 2022, 37(3): 655-666.
Qin Suya, Xue Yongduan, Liu Lizheng, et al.Transient characteristics and influence of small current grounding faults in active distribution network[J]. Transactions of China Electrotechnical Society, 2022, 37(3): 655-666.
[6] Ding Xiaobing, Shi Zebing, Yu Jiang, et al.Protection method of small current grounding system based on phase current variation[C]//2020 IEEE 4th Conference on Energy Internet and Energy System Integration (EI2), Wuhan, China, 2021: 243-247.
[7] 王晓卫, 刘伟博, 郭亮, 等. 基于不同时段内积投影的灵活接地系统高阻故障选线方法[J/OL]. 电工技术学报, 2023[2023-03-25].DOI:10.19595/j.cnki. 1000-6753.tces.221878.
Wang Xiaowei, Liu Weibo, Guo Liang, et al. High impedance fault line selection method based on inner product projection of different time periods for flexible grounding systems[J/OL]. Transactions of China Electrotechnical Society, 2023[2023-03-25]. DOI:10.19595/j.cnki. 1000-6753.tces.221878.
[8] 喻锟, 胥鹏博, 曾祥君, 等. 基于模糊测度融合诊断的配电网接地故障选线[J]. 电工技术学报, 2022, 37(3): 623-633.
Yu Kun, Xu Pengbo, Zeng Xiangjun, et al.Grounding fault line selection of distribution networks based on fuzzy measures integrated diagnosis[J]. Transactions of China Electrotechnical Society, 2022, 37(3): 623-633.
[9] 张明一, 孙元章, 黎雄, 等. 改进时域反演算法在配电网故障定位中的应用[J]. 电力系统自动化, 2021, 45(15): 101-108.
Zhang Mingyi, Sun Yuanzhang, Li Xiong, et al.Application of improved time reversal algorithm in fault location for distribution network[J]. Automation of Electric Power Systems, 2021, 45(15): 101-108.
[10] 明志强, 许虎. 经消弧线圈接地系统的中电阻快速选线方法[J]. 电网技术, 2009, 33(12): 112-114.
Ming Zhiqiang, Xu Hu.Fast line selection method of medium resistance in grounding system via arc suppression coil[J]. Power System Technology, 2009, 33(12): 112-114.
[11] 李振兴, 万佳灵, 王新, 等. 基于中值电阻投切的故障选线与定位新方法[J]. 电力系统保护与控制, 2021, 49(7): 57-65.
Li Zhenxing, Wan Jialing, Wang Xin, et al.A new method of fault line selection and location based on median resistance switching[J]. Power System Protection and Control, 2021, 49(7): 57-65.
[12] 邹浩斌, 胡少强, 刘利平, 等. 基于小扰动原理的单相接地选线装置[J]. 继电器, 2007, 35(2): 20-24.
Zou Haobin, Hu Shaoqiang, Liu Liping, et al.Single-phase grounding line selection device based on small disturbance principle[J]. Power System Protection and Control, 2007, 35(2): 20-24.
[13] 王建元, 张峥. 基于注入信号与小波能量的小电流接地故障选线研究[J]. 电测与仪表, 2018, 55(5): 28-32.
Wang Jianyuan, Zhang Zheng.Research on fault line selection of small current grounding based on injected signal and wavelet energy[J]. Electrical Measurement & Instrumentation, 2018, 55(5): 28-32.
[14] 栾晓明, 武守远, 贾春娟, 等. 基于改进零序导纳法的单相接地故障选线原理[J]. 电网技术, 2022, 46(1): 353-360.
Luan Xiaoming, Wu Shouyuan, Jia Chunjuan, et al.Fault line selection principle of single-phase-to-ground fault based on improved zero-sequence admittance[J]. Power System Technology, 2022, 46(1): 353-360.
[15] Costa F B, Souza B A, Brito N S D, et al. Real-time detection of transients induced by high-impedance faults based on the boundary wavelet transform[J]. IEEE Transactions on Industry Applications, 2015, 51(6): 5312-5323.
[16] 叶宝柱, 薛超宇, 张惠娟, 等. 基于特征频带小波包分析的配电网故障选线的研究[J]. 电气工程学报, 2018, 13(2): 24-28.
Ye Baozhu, Xue Chaoyu, Zhang Huijuan, et al.Research on fault line selection in distribution network based on feature band wavelet packet analysis[J]. Journal of Electrical Engineering, 2018, 13(2): 24-28.
[17] 贾清泉, 刘连光, 杨以涵, 等. 应用小波检测故障突变特性实现配电网小电流故障选线保护[J]. 中国电机工程学报, 2001, 21(10): 78-82.
Jia Qingquan, Liu Lianguang, Yang Yihan, et al.Abrupt change detection with wavelet for small current fault relaying[J]. Proceedings of the CSEE, 2001, 21(10): 78-82.
[18] 管廷龙, 薛永端, 徐丙垠. 基于故障相电压极化量的谐振接地系统高阻故障方向检测方法[J]. 电力系统保护与控制, 2020, 48(23): 73-81.
Guan Tinglong, Xue Yongduan, Xu Bingyin.Method for detecting high-impedance fault direction in a resonant grounding system based on voltage polarization of the fault phase[J]. Power System Protection and Control, 2020, 48(23): 73-81.
[19] 薛永端, 张秋凤, 颜廷纯, 等. 综合暂态与工频信息的谐振接地系统小电流接地故障选线[J]. 电力系统自动化, 2014, 38(24): 80-85.
Xue Yongduan, Zhang Qiufeng, Yan Tingchun, et al.Faulty feeder identification based on combined transient and power-frequency components in resonant grounded systems[J]. Automation of Electric Power Systems, 2014, 38(24): 80-85.
[20] 金鑫, 薛永端, 彭振华, 等. 仅利用零序电流的谐振接地系统接地故障方向算法[J]. 电力系统自动化, 2020, 44(9): 164-170.
Jin Xin, Xue Yongduan, Peng Zhenhua, et al.Grounding fault direction algorithm using zero-sequence current in resonant grounding system[J]. Automation of Electric Power Systems, 2020, 44(9): 164-170.
[21] 薛禹胜, 谢云云, 文福拴, 等. 关于电力系统相继故障研究的评述[J]. 电力系统自动化, 2013, 37(19): 1-9, 40.
Xue Yusheng, Xie Yunyun, Wen Fushuan, et al.A review on cascading failures in power systems[J]. Automation of Electric Power Systems, 2013, 37(19): 1-9, 40.
[22] 吴凤翔, 顾兆雄. 小电流接地系统两点接地故障仿真分析[J]. 上海电力大学学报, 2020, 36(6): 524-528.
Wu Fengxiang, Gu Zhaoxiong.Analysis of the cross-country grounded fault in the low current grounded system[J]. Journal of Shanghai University of Electric Power, 2020, 36(6): 524-528.
[23] 欧阳健娜, 俞小勇, 周杨珺, 等. 配网线路两点相继接地故障选线方法[J]. 南方电网技术, 2020, 14(6): 81-89.
Ouyang Jianna, Yu Xiaoyong, Zhou Yangjun, et al.A fault line selection method for two-point successive grounding of power distribution lines[J]. Southern Power System Technology, 2020, 14(6): 81-89.
[24] 吴争荣, 蔡颖倩, 张俊潇, 等. 消弧线圈接地系统同母多回线相继故障分析[J]. 高电压技术, 2017, 43(7): 2402-2409.
Wu Zhengrong, Cai Yingqian, Zhang Junxiao, et al.Fault analysis on successive fault of multi-feeders connected to the same bus in resonant grounding system[J]. High Voltage Engineering, 2017, 43(7): 2402-2409.
[25] 刘万顺, 黄少锋, 徐玉琴. 电力系统故障分析[M]. 3版. 北京: 中国电力出版社, 2010.
[26] 中华人民共和国住房和城乡建设部, 国家质量监督检验检疫总局. 城市配电网规划设计规范: GB 50613—2010[S]. 北京: 中国计划出版社, 2011.
[27] 徐丙垠, 薛永端, 李天友, 等. 小电流接地故障选线技术综述[J]. 电力设备, 2005(4): 1-7.
Xu Bingyin, Xue Yongduan, Li Tianyou, et al.Review of line selection of grounding fault in non - effectively grounding network techniques[J]. Electrical Equipment, 2005(4): 1-7.
[28] 李鑫. 配电线路单相接地故障定位及选线研究[D]. 北京: 华北电力大学, 2018. |
|
|
|
2023, Vol. 38 
