基于行波理论的10kV自闭/贯通线路故障测距技术

由于线路长、环境恶劣,10 kV自闭/贯通线路故障频繁发生,传统阻抗测距原理和基于线路监控终端的定位方法尚不能可靠、准确的确定故障(特别是小电流接地故障)位置,故障查找费时费力。利用故障产生的行波信号测量故障距离的方法已在输电线路获得成功应用。本文将行波测距原理应用到自闭/贯通线路,分析了自闭/贯通线路在接地及短路故障时产生的行波及其传输特征,并针对其线路结构的特殊性,提出了利用故障产生的电压行波信号线模分量、基于双端原理测量短路和接地等故障距离的模式,分析了实际应用中面临的行波信号获取等关键技术及故障初始相角、接地电阻、混合线路等对检测可靠性的影响。应用该方法的测距系统已在现场进行人工接地试验,并投入试运行,效果良好。该方法有望解决自闭/贯通线路故障定位这一难题。

Fault Location Based on Traveling Waves for 10 kV Automatic Blocking and Continuous Railway Power Lines

Due to the long distance and adverse corridor environment,there exists high fault probability on 10kV automatic blocking and continuous railway power lines(ABCRPLs).The fault locating methods based on impedance measurement or FTUs for ABCRPLs are not satisfactory both in reliability and accuracy.Fault location techniques using fault-generated current traveling waves have been applied to EHV transmission networks successfully.The fault location method based on traveling waves is applied to ABCRPLs in this paper.The characteristics of traveling waves of different kinds of faults are analyzed,and the fault location method for short circuit and earth faults in ABCRPL using the aerial model component of voltage traveling waves is proposed,which is based on the double ends(Type D) traveling wave principle.The key techniques to acquire traveling wave signals and the influences of fault resistances,inception angles and mixed lines on fault location reliability are analyzed too.A prototype fault location system was designed and tested with artificial faults on a ABCRPLs.Practical fault location results show the proposed technique has satisfactory reliability and accuracy.