摘要
为解决小电流接地系统单相接地故障特征不明显的问题,借助小波理论提出了基于DS证据理论的融合判据。首先确定小波基及小波分解尺度,并构造小波能量矩阵以确定故障特征频带。进而,在此特征频带下提取出三种故障特征:小波能量比、小波重构系数方差及暂态功率方向,并分析对比了三种特征的灵敏性。考虑到各个故障选线特征的检测灵敏性不同,为了提高选线准确率,进一步提出了基于DS证据理论的选线融合判据。最后,对现场实录波形进行分析。分析结果表明,该融合判据能够有机融合三种选线特征,提升选线正确率,具有较好的工程应用价值。
In order to solve the problem of single-phase ground fault characteristics of small current grounding system,the fusion criterion based on DS evidence theory is proposed by wavelet theory.Firstly,the wavelet base and wavelet decomposition scale are determined,and the wavelet energy matrix is constructed to determine the fault characteristic frequency band.Further,three fault characteristics,including wavelet energy ratio,wavelet reconstruction coefficient variance and transient power direction,are extracted in this characteristic frequency band,and the sensitivity of them is analyzed.Considering the different detection sensitivity of each fault line selection feature,the line selection fusion criterion based on DS evidence theory is further proposed in order to improve the line selection accuracy.Finally,the on-site recorded waveform is analyzed.The analysis results show that the fusion criterion can organically integrate three line selection features,improve the line selection accuracy,and has better engineering application value.
作者
邱进
田野
李冠华
杨帆
张鑫
牟龙华
QIU Jin;TIAN Ye;LI Guanhua;YANG Fan;ZHANG Xin;MU Longhua(China Electric Power Research Institute,Wuhan 430074,China;State Key Laboratory of Power Grid EnvironmentalProtection,Wuhan 430074,China;Research Institute of Liaoning Electric Power Co.Ltd.,Shenyang 110006,China;Department of Electrical Engineering,Tongji University,Shanghai 201804,China)
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2019年第6期180-187,共8页
Power System Protection and Control
基金
国家电网公司总部科技项目资助(GY71-17-032)"配电网复杂故障特征库及自适应辨识关键技术研究"~~
关键词
接地故障
小电流接地系统
小波分析
故障特征
DS证据理论
ground fault
neutral indirectly grounding system
wavelet analysis
fault characteristic
DS evidence theory
