谐振接地系统暂态波形差异性识别法接地选线  

Faulty line detection based on transient waveform difference recognition for resonant earthed system

作　　者：郭谋发[1] 高源[1] 杨耿杰[1] 

机构地区：[1]福州大学电气工程与自动化学院,福建福州350108

出　　处：《电力自动化设备》2014年第5期59-66,共8页Electric Power Automation Equipment

摘　　要：利用谐振接地系统发生单相接地故障时,故障线路与非故障线路间的暂态零序电流波形差异性大于非故障线路间的暂态零序电流波形差异性的特点,提出一种基于暂态波形差异性识别的接地选线新方法。对各线路故障暂态零序电流波形进行小波包分解、重构及信号增强处理,根据各频带频率大小确定该频带的时间窗的划分数量,求取各组时间窗波形的分布特征矩阵及其相互间的相对熵,用于衡量同组时间窗波形间的差异程度,采用等权重投票法统计各频带各组时间窗的初步选线结果并确定故障线路。大量仿真结果表明该选线方法选线准确、可靠。When single-phase grounding fault occurs in resonant earthed system,the transient zero-sequence current waveform difference between faulty line and healthy line is bigger than that between healthy lines, based on which,an approach of faulty line detection is put forward. The wavelet packet decomposition, reconstruction and information enhancement are carried out for the fault transient zero-sequence current waveform of each line and the amount of time windows is determined for each frequency band according to its size. The distribution feature matrixes of each time window and its relative entropy are calculated and then used to recognize the waveform difference degree among the same time window of different lines. The faulty line is then picked out by the equal weight voting from the candidate faulty lines selected during waveform difference recognition for different time windows, Substantial simulative results show its accuracy and reliability.

关 键 词：接地选线 小波包变换 相对熵 波形差异性识别 等权重投票 谐振 接地 

分 类 号：TM711[电气工程—电力系统及自动化]