小电流接地故障零序电压分布特征与测距

Zero-sequence Voltage Distribution Characteristics and Location of Non-solidly Grounding Fault

配电线路小电流接地故障测距技术存在准确度与经济性难以兼顾的问题。首先,通过建立小电流接地系统分布参数等值电路,分析了小电流接地故障后故障线路的零序电压分布特征。然后,考虑配电线路的复杂情况,提出了多种故障线路零序电压分布函数获取方法。最后,根据故障点上、下游区段的零序电压分布函数,计算出故障点的位置。所提方法原理简单,因为利用了已有配电网自动化系统相关设备,经济性好。仿真结果表明,所提方法在正确选出故障所在区段的情况下测距精度较高。

It is difficult to balance the accuracy and economy of non-solidly grounding fault location technology of distribution lines.Firstly,the zero-sequence voltage distribution characteristics of the fault line after the non-solidly grounding fault are analyzed by establishing the equivalent circuit of the distribution parameters of the non-solidly grounding system.Then,considering the complexity of distribution lines,a method to obtain the zero-sequence voltage distribution function of various fault lines is proposed.Finally,the location of the fault point is calculated according to the zero-sequence voltage distribution function of the upstream and downstream line sections of the fault point.The principle of the proposed method is simple.Because the existing distribution automation system and related equipment are used,the economy is good.The simulation results show that the fault location accuracy of the proposed method is high when the fault section is correctly selected.