谐振接地电网故障选线相关分析法  

Correlation analysis for faulty feeder detection in resonant earthed system

作　　者：束洪春[1,2] 徐亮[3] 彭仕欣[4] 孙向飞[2] 

机构地区：[1]昆明理工大学电力学院,云南昆明650051 [2]哈尔滨工业大学电气工程系,黑龙江哈尔滨150001 [3]嘉兴电力局,浙江嘉兴314000 [4]昆明供电局,云南昆明650051

出　　处：《电力自动化设备》2008年第9期6-9,48,共5页Electric Power Automation Equipment

基　　金：国家自然科学基金资助项目(90610024;50467002;50347026);云南省科技攻关项目(2003GG10);云南省自然科学基金项目(2005F0005Z;2004E0020M;2002E0025M)~~

摘　　要：对于谐振接地电网,发生故障前,故障馈线与健全馈线零模电流中的不对称分量具有较强的相似性,它们之间的互相关系数会受到不对称分量的影响。对各线路故障零模电流,用故障发生之后第1个周期采样数据对应减去故障发生前1个周期采样数据,得到零模电流的纯故障分量。提出一种基于零模电流纯故障分量的相关分析选线方法,对各馈线故障零模电流的纯故障分量在一定数据窗下进行综合相关度分析,选择最小的综合相关系数对应的馈线为故障馈线。该选线方法具有较强的抗电弧接地能力,能有效地克服系统不对称的影响。理论分析及仿真结果表明,该方法选线结果准确、可靠,进一步提高了选线保护的裕度。The zero modulus current asymmetric components of faulty line are very similar to those of healthy line in resonant earthed system before incident,which strongly influences their correlation coefficient. The pure fault component of zero modulus current can be obtained by subtracting the sampled data of the first cycle zero modulus current before fault from those of the first cycle zero modulus current after fault. A faulty line detection method based on the correlation analysis is proposed,which analyzes under certain data window the integrated correlation coefficient of pure fault component of zero modulus current for each feeder and takes the line with the smallest one as the faulty line. Theoretical analysis and simulative results show that,the proposed method is accurate and reliable,with the enhanced protection margin and the excellent performance in arc earthing detection and asymmetric component impact suppression.

关 键 词：谐振接地系统 故障选线 纯故障分量 相关分析 

分 类 号：TM712[电气工程—电力系统及自动化]