基于改进EMD算法的小电流接地故障选线

摘要/Abstract

摘要：

小电流接地系统发生单相接地故障,故障电流暂态分量复杂、稳态分量不明显的特点为可靠选线带来困难。本文分析了小电流接地故障电流暂态分量特征,并提出一种基于改进EMD算法的小电流接地故障选线方法。EMD算法通过叠加电网特征高频信号解决了IMF模态混叠并可靠滤除了高频干扰。基于单相接地故障电流经改进EMD分解出的IMF在不同故障角下展现出不同的特征,分别利用故障时刻低频波形的单调性与线路故障特征能量作为判据进行小电流接地故障选线。基于Matlab/Simulink的配电网单相接地故障仿真验证了该选线方法的有效性。

关键词: 小电流接地系统, 故障选线, 改进EMD算法, 特征频带, 故障特征能量

Abstract:

As single-phase earth fault occurs in the small current grounding system, the complex transient and unconspicuous steady-state component of fault current bring certain difficulties for reliable fault line selection. The transient component characteristics of fault current in the small current grounding system are analyzed and a method about fault line selection based on improved EMD algorithm is put forward in this paper. The method of solving the IMF modal aliasing problems by overlaying the characteristic high frequency signal in EMD algorithm also reliable filter high frequency noise. It can be used in different fault time. In view of IMF which get by the improved EMD algorithm under different fault angle show different characteristics, the low frequency waveform monotonicity in the fault time and the fault characteristic energy can be used to determine the fault line. At last the effectiveness of the proposed fault line selection methods is verified by the simulation results of the single-phase earth fault in distribution network built in Matlab/Simulink.

Key words: Small current grounding system, fault line selection, improved EMD algorithm, characteristic frequency band, fault characteristic energy

中图分类号:

TM74

王磊,骆玮,曹现峰. 基于改进EMD算法的小电流接地故障选线[J]. 电气工程学报, 2015, 10(8): 29-34.

Wang Lei,Luo Wei,Cao Xianfeng. Fault Line Selection Based on Improved EMD Algorithm for Small Current Grounding System[J]. Journal of Electrical Engineering, 2015, 10(8): 29-34.

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参考文献 16

[1]	李斌, 束洪春 . 基于瞬时实功率和瞬时虚功率的谐振接地系统单相接地选线新方法[J]. 电工技术学报, 2012,27(6):183-190.
	Li Bin, Shu Hongchun . A new integration method of fault line detection in resonant earthed system based on instantaneous real power and instantaneous virtualpower[J]. Transactions of China Electrotechnical Society, 2012,27(6):183-190.
[2]	贾清泉, 石磊磊, 王宁 , 等. 基于证据理论和信息熵的消弧线圈接地电网融合选线方法[J]. 电工技术学报, 2012,27(6):191-197.
	Jia Qingquan, Shi Leilei, Wang Ning , et al. A fusion method for ground fault line detection in compensated power networks based on evidence theory and information entropy[J]. Transactions of China Electrotechnical Society, 2012,27(6):191-197.
[3]	张淑清, 马跃, 李盼 , 等. 基于改进的广义谐波小波包分解和混沌振子的小电流接地系统故障选线[J]. 电工技术学报, 2015,30(3):13-20.
	Zhang Shuqing, Ma Yue, Li Pan , et al. Application of improved generalized harmonic wavelet packet decomposition and chaos oscillator to fault Line detection in small current grounding system[J]. Transactions of China Electrotechnical Society, 2015,30(3):13-20.
[4]	薛永端, 高旭, 苏永智 , 等. 小电流接地故障谐波分析及其对谐波选线的影响[J]. 电力系统自动化, 2011,35(6):60-64.
	Xue Yongduan, Gao Xu, Su Yongzhi , et al. Analysis of harmonic innon-solidly earthed network and its influences on harmonic-basedearthfault protection[J]. Automation of Electric Power Systems, 2011,35(6):60-64.
[5]	王耀南, 霍百林, 王辉 , 等. 基于小波包的小电流接地系统故障选线的新判据[J]. 中国电机工程学报, 2004,24(6):54-58.
	Wang Yaonan, Huo Bailin, Wang Hui , et al. A new criterion for earth fault line selection based on wavelet packets in small current neutral grounding system[J]. Proceedings of the CSEE, 2004,24(6):54-58.
[6]	龚静 . 小波分析在配网单相接地故障选线中的应用[M]. 北京: 中国电力出版社, 2012.
[7]	毕研秋, 赵建国 . 基于暂态量和小波包的配电网故障选线方法[J]. 电力自动化设备, 2007,27(6):17-21.
	Bi Yanqiu, Zhao Jianguo . Faulty feeder detection based on transient current andwavelet packet in distribution system[J]. Electric Power Automation Equipment, 2007,27(6):17-21.
[8]	任建文, 孙文武, 周明 , 等. 基于数学形态学的配电网单相接地故障暂态选线算法[J]. 电力系统自动化, 2008,32(1):70-75.
	Ren Jianwen, Sun Wenwu, Zhou Ming , et al. Transient algorithm for single-line to ground fault selection in distribution networks based on mathematical morpho-logy[J]. Automation of Electric Power Systems, 2008,32(1):70-75.
[9]	李天云, 赵妍, 季小慧 , 等. HHT方法在电力系统故障信号分析中的应用[J]. 电工技术学报, 2005,20(6):87-91.
	Li Tianyun, Zhao Yan, Ji Xiaohui , et al. Application of HHT method for analysis of fault signal in electric power system[J]. Transactions of China Electric Technical Society, 2005,20(6):87-91.
[10]	张宇辉, 汪利君, 兰华 , 等. 基于EMD-相关性算法的谐振接地系统故障选线新方法[J]. 电测与仪表, 2012,49(12):7-11. doi: 10.1371/journal.pone.0226751 pmid: 31887160
	Zhang Yuhui, Wang Lijun, Lan Hua , et al. A method of resonant earthed system fault line detection based on EMD[J]. Electrical Measurement & Instrumentation, 2012,49(12):7-11. doi: 10.1371/journal.pone.0226751 pmid: 31887160
[11]	Huang N E, Zheng S, Steven R , et al. The empirical mode decomposition and Hilbert spectrum for nonlinear and nonstationary time series analysis[J]. Proceedings of the Royal Society of London, 1998,454:903-995. doi: 10.1007/s11517-006-0065-x pmid: 16937193
[12]	赵玲, 刘小峰, 秦树人 , 等. 消除经验模态分解中混叠现象的改进掩膜信号法[J]. 振动与冲击, 2010,29(9):13-17,239.
	Zhao Ling, Liu Xiaofeng, Qin Shuren , et al. Use of masking signal to improve empirical mode decomposition[J]. Journal of Vibration and Shock, 2010,29(9):13-17, 239.
[13]	薛永端, 李娟, 徐丙垠 . 中性点不接地系统小电流接地故障暂态等值电路的建立[J]. 中国电机工程学报, 2013,33(34):223-232.
	Xue Yongduan, Li Juan, Xu Bingyin . Construction of transient equivalent circuits of single-phase earth fault for isolated neutral systems[J]. Proceedings of the CSEE, 2013,33(34):223-232.
[14]	王建元, 鞠默欣, 徐志璇 , 等. 基于HHT小电流接地故障选线与在线故障定位方法[J]. 电测与仪表, 2014,51(15):48-54. doi: 10.1371/journal.pone.0226751 pmid: 31887160
	Wang Jianyuan, Ju Moxin, Xu Zhixuan , et al. An HHT based method of fault line selection and online fault location in neutral point ineffectively grounded power system[J]. Electrical Measurement & Instrumentation, 2014,51(15):48-54. doi: 10.1371/journal.pone.0226751 pmid: 31887160
[15]	王娜娜, 刘涤尘, 廖清芬 , 等. 基于EMD-TEO及信号能量分析法的主导低频振荡模式识别[J]. 电工技术学报, 2012,27(6):198-204.
	Wang Nana, Liu Dichen, Liao Qingfen , et al. Identification of the dominant inertial mode based on EMD-TEO and signal energy method[J]. Transactions of China Electrotechnical Society, 2012,27(6):198-204.
[16]	束洪春, 赵文渊, 彭仕欣 . 配电网缆—线混合线路故障选线的 HHT 检测方法[J]. 电力自动化设备, 2009,29(5):4-9.
	Shu Hongchun, Zhao Wenyuan, Pen Shixin . Faulty line selection based on HHT detection for hybrid distribution network[J]. Electric Power Automation Equipment, 2009,29(5):4-9.

支路	30°故障角		60°故障角		90°故障角
支路	故障特征能量	中心频率/Hz	故障特征能量	中心频率/Hz	故障特征能量	中心频率/Hz
1	19 093	3 400	57 297	3 400	75 067	3 400
2	17 219	2 000	53 063	2 000	66 433	2 000
3	61 325	1 300,2 000,3 400	217 610	1 300,2 000,3 400	233 450	1 300,2 000,3 400
4	33 986	1 300	102 810	1 300	129 650	1 300