Abstract：Due to the frequent malfunctions of relay protection system caused by low-frequency oscillation current of Metro DC traction network, more effective feature extraction methods are in need to improve the reliability of protection system. The extraction method combined empirical mode decomposition(EMD) and energy weight can effectively distinguish oscillation current and fault current of traction network, and achieve the extraction of dynamic feature information in traction network current. In this method, the traction network current is decomposed by EMD and the energy weight of each intrinsic mode function(IMF) is calculated, and the feature vector of fault pattern recognition is obtained by constructing the multi-scale feature entropy based on energy weight. The actual measurement data illustrates that the new method not only can accurately identify oscillation current and fault current of traction network, but also has the advantages of clear concept and simple algorithm.
田行军, 李夏青, 李运华. 直流牵引网振荡电流与故障电流波形识别[J]. 电工技术学报, 2013, 28(11): 247-253.
Tian Xingjun, Li Xiaqing, Li Yunhua. Waveform Identification of Oscillation Current and Fault Current in DC Traction Network. Transactions of China Electrotechnical Society, 2013, 28(11): 247-253.
[1] 郎兵. 直流牵引供电系统馈线保护的研究[J]. 北京交通大学学报, 2009, 33(5): 65-68. Lang Bing. Research on feeder protection for DC traction power supply system[J]. Journal of Beijing Jiaotong University, 2009, 33(5): 65-68. [2] 王广峰, 孙玉坤, 陈坤华. 地铁直流牵引供电系统中的DDL保护[J]. 电力系统及其自动化学报, 2007, 19(1): 59-62. Wang Guangfeng, Sun Yukun, Chen Kunhua. DDL protection in subway DC traction power supply system[J]. Proceedings of the CSU-EPSA, 2007, 19(1): 59-62. [3] Brown J C, Allan J, Mellitt B. Calculation of remote short circuit fault currents for DC railways[J]. IEE Proceedings-B, 1992, 13(4): 289-294. [4] Yu L, He J H, Bo Z Q, et al. A new DC feeder protection based on wavelet transform[C]. IEEE Bucharest Power Tech Conference, 2009: 1-5. [5] 李夏青, 左丽. 直流牵引网故障电流能量谱及特征矢量[J]. 电工技术学报, 2010, 25(11): 164-168. Li Xiaqing, Zuo Li. Energy spectrum and eigenvector of DC traction power supply short-circuit current[J]. Transactions of China Electrotechnical Society, 2010, 25(11): 164-168. [6] 李辉, 王瀚, 白亮, 等. 改进希尔伯特-黄变换方法提取水轮机动态特征信息[J]. 中国电机工程学报, 2011, 31(2): 78-84. Li Hui, Wang Han, Bai Liang, et al. Dynamic characteristic information extraction of hydroturbine based on improved Hilbert-Huang transform method[J]. Proceedings of the CSEE, 2011, 31(2): 78-84. [7] 杨江天, 周培钰. 经验模态分解和Laplace小波在机车柴油机齿轮系故障诊断中的应用[J]. 机械工程学报, 2011, 47(7): 109-115. Yang Jiangtian, Zhou Peiyu. Fault diagnosis for gear train of locomotive diesel engine based on empirical mode decomposition and Laplace wavelet[J]. Journal of Mechnical Engineering, 2011, 47(7): 109-115. [8] 牛杰, 刘永祥, 秦玉亮, 等. 一种基于经验模态分解的锥体目标雷达微动特征提取新方法[J]. 电子学报, 2011, 39(7): 1712-1715. Niu Jie, Liu Yongxiang, Qin Yuliang, et al. A new method of radar micro-motion feature extraction of cone target based on empirical mode decomposi- tion[J]. Acta Electronica Sinica, 2011, 39(7): 1712-1715. [9] 李成鑫, 刘俊勇, 杨嘉湜, 等. 频移经验模态分解在低频振荡参数提取中的应用[J]. 电力系统自动化, 2011, 35(20): 1-6. Li Chengxin, Liu Junyong, Yang Jiashi, et al. Frequency shift empirical mode decomposition for extracting low frequency oscillation parameters[J]. Automation of Electric Power Systems, 2011, 35(20): 1-6. [10] 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.
2013, Vol. 28 
