基于中值电阻投切的故障选线与定位新方法  

A novel method of fault line selection and section location based on the input and cutoff of medium resistance

作　　者：李振兴[1] 万佳灵 王新 翁汉琍[2] 李振华[1] LI Zhenxing;WAN Jialing;WANG Xin;WENG Hanli;LI Zhenhua(College of Electrical Engineering&New Energy,China Three Gorges University,Yichang 443002,China;Key Laboratory of Cascaded Hydropower Stations Operation&Control,China Three Gorges University,Yichang 443002,China)

机构地区：[1]三峡大学电气与新能源学院,湖北宜昌443002 [2]梯级水电站运行与控制湖北省重点实验室(三峡大学),湖北宜昌443002

出　　处：《电力系统保护与控制》2021年第7期57-65,共9页Power System Protection and Control

基　　金：国家自然科学基金项目资助(52077120);三峡大学学位论文培优基金项目资助(2021SSPY056)。

摘　　要：消弧线圈接地系统并联中值电阻为故障选线与定位增大了信息的可利用度,基于此提出利用中值电阻投入前后工频增量系数的选线与定位方法。分析了中值电阻在系统故障时的投切时间,并梳理了投入前后零序电流工频信息的故障特征及其差异性。研究发现在投切电阻时故障线路零序电流分量突增而健全线路零序电流分量降低;故障区段的上游段零序电流分量突增而下游段零序电流分量降低。针对此差异性,计算投入电阻前后零序电流分量半周积分值的比值为工频增量系数K,基于故障线路与健全线路的K值比较及故障区段的上游与下游K值比较,实现故障选线和区段定位。利用Matlab/Simulink建立混合电缆-架空线系统仿真模型,仿真结果验证了所提出选线定位方法的有效性。An arc suppression coil-grounded system with medium resistance increases the availability of information for fault line selection and section location.This paper proposes a novel method of fault line selection and section location based on the increment coefficient of power frequency.It analyses the input time and the cutoff time of medium resistance when the system fails and explains the fault characteristics and differences of power frequency information of zero sequence current between the input and the cutoff of medium resistance.Research shows that the zero-sequence current component of a fault line increases rapidly and the zero-sequence current component of a healthy line decreases.The zero sequence current component of a fault section upstream increases rapidly and downstream it decreases.Aiming at the difference,the half cycle integral values of zero sequence current component are calculated as an increment coefficient of power frequency K.Based on the comparison of the K value of the fault line and a healthy line,and the K value between upstream and downstream in the fault section,the method achieves fault line selection and section location.A hybrid cable-overhead line system simulation model is established in Matlab/Simulink,and results verify the effectiveness of the fault line selection and location method.

关 键 词：消弧线圈接地系统 并联中值电阻 故障选线与定位 零序电流工频分量 增量系数 

分 类 号：TM862[电气工程—高电压与绝缘技术]