基于改进阻抗法的配电变压器低压故障越级跳闸故障定位方法  

Fault Location Method for Low Voltage Fault Overstep Trip of Distribution Transformer Based on Improved Impedance Method

作　　者：杨超 郭文奇 熊姚意 李权 安军 曾清竹 Yang Chao;Guo Wenqi;Xiong Yaoyi;Li Quan;An Jun;Zeng Qingzhu(Longnan Power Supply Branch,Gansu Electric Power Company,Longnan Gansu 746099,China;School of Electrical and Electronic Information,Xihua University,Chengdu Sichuan 610039,China)

机构地区：[1]国网甘肃省电力公司陇南供电公司,甘肃陇南746099 [2]西华大学电气与电子信息学院,四川成都610039

出　　处：《电气自动化》2023年第3期11-14,共4页Electrical Automation

基　　金：国家自然科学基金资助项目(51877181);国网甘肃省电力公司科技项目(5227122000J6)。

摘　　要：现代配电网由于线路分支繁多,时常面临着配变低压故障越级却难以及时分析定位的情况。为此将等效电气距离坐标值和故障指示器相结合,提出了一种基于改进阻抗法的故障定位方法。采用母线故障前空载电压进行计算,避开了母线短路时暂态电压不稳定导致故障回路阻抗计算不稳定的问题,及时查找出可能发生配变低压故障越级的配变名称及杆号路径坐标,并发布信息给管理人员。通过对某地区两县级电网实际案例进行分析,验证了方法的有效性。结果表明,所提方法减少了线路故障巡视工作量和成本,大幅降低故障停电时间。Due to the variety of line branches,the modern distribution network is often faced with the situation that the low voltage fault of the distribution transformer exceeds the level,but it is difficult to analyze and locate it in time.Therefore,a fault location method based on the improved impedance method was proposed by combining the equivalent electrical distance coordinate value with the fault indicator.The no-load voltage before bus fault was adopted for calculation,which avoided the problem of unstable calculation of fault loop impedance caused by unstable transient voltage during bus short circuit,and can timely find out the name and pole number path mark of distribution transformer that may exceed the level of low-voltage fault of distribution transformer,and release information to managers.The effectiveness of the method was verified by analyzing the actual cases of two county-level power grids in a region.The results show that the proposed method reduces the workload and cost of line fault inspection,and greatly reduces the outage time.

关 键 词：故障定位 故障越级跳闸 阻抗法 等效电气距离坐标 故障测距 

分 类 号：TM77[电气工程—电力系统及自动化]