配电网单相接地故障定位技术实验研究

配电网中单相接地故障发生概率最大,传统的故障定位方法不能有效解决配电网多分支、长线路、高电阻等故障定位难题。研究发现,直流定位法不受分支数量、过渡电阻和线路长度的影响,能够较好地解决配电网定位难题。通过仿真和现场实验证实了直流定位法的可行性;在直流法的基础上,为简化定位操作,提出60Hz交流定位法,该方法可以地面检测,大大缩短定位时间。实验证明,直流法和交流法结合的综合定位法是配电网故障定位的可行方法。

Experimental Research on Single-phase-to-ground Fault Location in Distribution Network

Single-phase-to-ground fault occurs most frequently in a distribution network.But conventional fault location methods cannot effectively solve this location problem due to several characteristics of the distribution network,e.g.multi-branches,long lines and high grounding resistance.Researches reveal that the DC location method is not influenced by these factors and can be used in solving fault location problem in distribution networks.Simulation and field tests have proved the feasibility of this method.To simplify the fault location operation with DC location method,a 60 Hz AC location method is recommended to shorten the locating time since the AC signal can be detected on the ground.Finally,field tests show that the proposed compositive location method combining AC and DC methods can effectively locate the fault point of the distribution network.