摘要
目前,针对小电流接地系统单相接地故障特征的理论分析已经成熟,但对两点相继接地故障暂态特征的研究较少,其与普通单相接地故障的暂态电气量差异以及已有暂态选线方法的适用性尚不明确。针对小电流接地系统跨线同名相和异名相两点相继接地故障暂态特征问题,建立了后发低阻接地故障暂态等值电路,对故障线路暂态特征进行理论分析并与其单独接地时暂态电气量进行了比较,得到了故障线路暂态特征随不同故障条件(过渡电阻、线路电感、系统对地电容、后发故障相)的变化规律,证明了部分暂态选线方法不再适用于后发接地故障并提出了基于连续检测的选线方法。最后,通过数字仿真和现场数据验证了文中分析结果的正确性。
At present,the theoretical analysis of single-phase grounding fault characteristics for non-solidly grounded systems has been mature,but there are few studies on the transient characteristics of two-point successive grounding faults.The differences in transient electrical quantities between cross-line successive grounding faults and normal single-line grounding faults and the applicability of existing transient line selection methods are still unclear.In order to solve the problem of transient characteristics of two-point successive grounding faults of the same and different phases in a non-solidly grounded system,a transient equivalent circuit of subsequent low-impedance grounding fault is established.The transient characteristics of fault lines are analyzed and compared with the transient electrical quantities of normal single-phase grounding fault.The transient characteristics of fault lines vary with different fault conditions,such as transition resistance,inductance,capacitance to ground,and successive fault phase.It is proven that the partial transient line selection methods are no longer suitable for subsequent grounding faults and a line selection method based on continuous detection is proposed.Finally,the correctness of the analysis results is verified by digital simulation and field data.
作者
亓志滨
薛永端
刘健
王超
徐丙垠
张小庆
QI Zhibin;XUE Yongduan;LIU Jian;WANG Chao;XU Bingyin;ZHANG Xiaoqing(College of New Energy,China University of Petroleum(East China),Qingdao 266580,China;Electric Power Institute of State Grid Shaanxi Electric Power Company,Xi’an 710100,China;Shandong Kehui Power Automation Co.,Ltd.,Jinan 250101,China;Research Center for Smart Grid,Shandong University of Technology,Zibo 255049,China)
出处
《电力系统自动化》
EI
CSCD
北大核心
2023年第19期156-165,共10页
Automation of Electric Power Systems
基金
国家自然科学基金资助项目(52077221)。
关键词
配电网
小电流接地系统
相继接地故障
暂态特征
暂态选线
distribution network
non-solidly grounded system
successive grounding fault
transient characteristic
transient line selection
