摘要
为了提高配电网系统单相接地故障判别的快速性、精确性和可靠性,论文针对配网系统特征、配网单相接地稳态量以及配网单相接地暂态量展开分析,围绕负序分量开展单相接地故障序特性研究。通过建立单相接地的序特性模型,可计算空间负序电流有效值,以此作为判据可识别单相接地故障和故障线路,从而形成一套完整的单相接地故障判别方法。通过在线路不同位置设置单相接地故障进行仿真测试,仿真结果表明,若故障电阻维持不变,在线路各个故障位置下,所获得的空间负序电流有效值皆能满足故障判据,且不受故障点位置的影响。同时,故障距离越远,所测电流有效值越小,因而需要在空间负序电流有效值所在的范围内合理设定阈值才能保障故障类型识别的精确性和可靠性。
In order to improve the speed, accuracy and reliability of the single-phase ground fault identification of the distribution network system, this paper analyzes the characteristics of the distribution network system, the single-phase grounding steady-state quantity and the single-phase grounding transient quantity of the distribution network. The sequence component carries out the research on the sequence characteristics of single-phase ground faults. By establishing the sequence characteristic model of single-phase ground fault, the RMS value of the spatial negative sequence current can be calculated, which can be used as a criterion to identify single-phase ground faults and faulted lines, thus forming a complete set of single-phase ground fault discrimination method. Through the simulation test by setting up single-phase ground faults at different locations of the fault line, the test results show that if the fault resistance remains unchanged, the RMS value of the space negative sequence current obtained at each fault location of the fault line can meet the fault criterion, and not affected by the location of the fault point. At the same time, the farther the fault distance is, the smaller the RMS value of the measured current. Therefore, it is necessary to set a reasonable threshold within the range of the RMS value of the spatial negative sequence current to ensure the accuracy and reliability of fault type identification.
作者
付宇
刘安茳
肖小兵
郑友卓
张洋
郝树青
FU Yu;XIAO Xiaobing;LIU Anjiang;ZHENG Youzhuo;Zhang Yang;Hao Shuqing(Electric Power Research 1nstitute of Guizhou Power Grid Co.,Ltd.,Guiyang 550002 Guizhou,China)
出处
《电力大数据》
2021年第6期84-92,共9页
Power Systems and Big Data
关键词
单相接地故障
空间负序矢量
序电流
故障辨识
配电网
single-phase ground fault
spatial negative sequence vector
sequence current
fault identification
power distribution network
