基于零序电流的环网柜接地故障检测方法研究  

Research on ground fault detection method of ring main unit based on zero sequence current

作　　者：任鹏 赵彤[1] REN Peng;ZHAO Tong(Qingdao University of Science and Technology,Collage of Automation and Electronic Engineering,Qingdao,Shandong 266061,China;Qingdao Engineering Vocational College,Training Department,Qingdao,Shandong 266112,China)

机构地区：[1]青岛科技大学自动化与电子工程学院,山东青岛266061 [2]青岛工程职业学院培训处,山东青岛266112

出　　处：《自动化与仪器仪表》2023年第7期231-234,共4页Automation & Instrumentation

摘　　要：为了及时对环网柜电缆接地线故障点进行精准检测,避免因接地故障造成大规模停电等严重后果,提出基于零序电流差法的电缆接地故障检测方法。首先探究电缆接地故障检测原理,对通过零序电流差值判断线路是否发生接地故障的方法进行理论分析;然后搭建了中性点直接接地和中性点经消弧线圈接地两种接地方式的配电网模型,并建立了Matlab/Simulink仿真模型,提出利用偏置电容在单相接地和两相接地两种情况下,分别对故障前后线路对地分布参数进行求解,根据故障前后对地分布参数的变化,进而判断哪相接地发生故障。通过实验可知,该种方法不受接地方式的影响,对高阻接地也可以进行准确判断,具有很好的通用性。To timely and accurately detect the failure point of cable grounding wire of ring main unit and avoid serious consequences,including large-scale power fault caused by grounding fault,the article proposes to study the cable grounding fault detection based on zero sequence current difference method.Firstly,through exploring the principle of cable grounding fault detection,the judgement on whether the line happened with grounding fault through the difference of zero sequence current was theoretically analyzed;then,through construct the distribution network model by two grounding methods,neutral point direct grounding and neutral point arc suppression coil ground,and establishing Matlab/Simulink simulation model.The article solves the line-to-ground distribution parameters before and after the fault by applying the single-phase grounding and two-phase grounding of bias capacitor.According to the change of grounding distribution parameters before and after the fault,it was of importance to judge which phase caused grounding fault.The experiment has demonstrated that this method is free from the requirement of ground,and is capable of accurately judging the high-resistance grounding,which has a good performance in universality.

关 键 词：环网柜 接地故障检测 高阻接地 

分 类 号：TP276[自动化与计算机技术—检测技术与自动化装置] TM712[自动化与计算机技术—控制科学与工程] TM727.2[电气工程—电力系统及自动化]