基于零序导纳变化的跨线异名相两点相继接地故障检测  

Cross-line Different-phase Two-point Successive Grounding Fault Detection Based on Change of Zero-sequence Admittance

作　　者：薛永端[1] 亓志滨 蔡卓远 仉志华[1] 王超[2] 徐丙垠[2] XUE Yongduan;QI Zhibin;CAI Zhuoyuan;ZHANG Zhihua;WANG Chao;XU Bingyin(College of New Energy,China University of Petroleum(East China),Qingdao 266580,China;Research Center for Smart Grid,Shandong University of Technology,Zibo 255049,China)

机构地区：[1]中国石油大学(华东)新能源学院,山东省青岛市266580 [2]山东理工大学智能电网研究院,山东省淄博市255049

出　　处：《电力系统自动化》2023年第7期174-183,共10页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(52077221)。

摘　　要：小电流接地系统中普通单相接地的故障检测技术已逐渐成熟,但一些特殊的接地故障的特征与检测方法仍需深入研究。文中针对不接地系统与谐振接地系统发生的跨线异名相两点相继接地故障,建立了等值电路模型,分析了后发接地故障前后故障路径与非故障路径的电气量特征。分析发现非故障路径零序导纳始终不变,而在两个接地点过渡电阻均小于3000Ω的条件下,故障路径零序导纳的模值或相角至少有一项存在明显差异。基于此,提出了基于零序导纳变化的小电流接地系统跨线异名相两点相继接地时后发故障检测方法,可进一步实现后发故障选线与定位。基于数字仿真和实际故障数据验证了故障特征分析的正确性与检测方法的可行性。The fault detection technology of common single-phase grounding fault in non-solidly grounded system has gradually matured,but the characteristics and detection methods for some special grounding faults still need further study.In this paper,the equivalent circuit model is established for the cross-line different-phase two-point successive grounding fault in the non-grounded system and the resonant grounded system,and the electrical characteristics of the fault path and the non-fault path before and after the grounding fault are analyzed.The analysis shows that the zero-sequence admittance of the non-fault path remains unchanged,but under the condition that the transition resistance of the two grounding points is less than 3000Ω,there is a significant difference in at least one of the module values or phase angles of the zero-sequence admittance of the fault path.Based on this,a method for detecting the later fault of the cross-line different-phase two-point successive grounding faults in non-solidly grounded system based on the change of zero-sequence admittance is proposed,which can further realize the later fault line selection and location.Based on digital simulation and actual fault data,the correctness of fault feature analysis and the feasibility of detection method are verified.

关 键 词：小电流接地系统 跨线故障 异名相两点相继接地 零序导纳 故障检测 

分 类 号：TM862[电气工程—高电压与绝缘技术]