配电线路行波故障测距初探

探索综合利用故障初始电流、电压行波线模分量实现配电线路双端故障测距的新方法。根据不同配电线路的结构特点,分别提出了“电流-电压”、“电压-电压”和“电流-电流”3种双端行波测距模式。简要分析了小电流接地故障及相间短路故障的行波特征,阐述了故障行波信号的获取、故障过渡电阻、配电网混合线路、多分支线路以及行波波头的准确标定等影响故障测距的关键技术问题。提出利用线路末端配电变压器传变电压行波,解决配电线路末端行波信号不易获取的问题。最后通过现场试验初步验证了该方法的可行性。

Fault Location for Distribution Feeders Based on Traveling Waves

A new method of fault location for distribution feeders based on the aerial mode component of fault generating current and voltage traveling waves is discussed. Considering different distribution feeders, the current-voltage mode, the voltage-voltage mode and the current-current mode for fault location are proposed. Characteristics of traveling waves for small current earth fault and inter-phase short circuit fault are analyzed. Some key techniques are expatiated, such as the measurement of fault generating traveling wave signals, the fault transition resistance, the mixed lines and the lines with multi branches, the precise detection of traveling wave pulse, and so on. Moreover, distribution transformer is used to transform transient voltage traveling waves for overcoming the difficulty to catch the traveling waves at feeders' terminals. Field tests have verified the feasibility of the method proposed.