计及架空地线的配电线路雷电感应过电压模型及应用

Lightning Induced Over-voltage Model and Application inDistribution Lines With Overhead Ground Wires

该文提出一种基于MODELS语言计算雷电感应过电压的工程模型方法。用于对雷电通道建模以及与架空线路的电磁耦合进行了分析,并在ATP/EMTP中实现且验证。方法考虑了有损地面对径向电场的影响,能够搭建适用于用于配电网输电线路及架空线路的感应雷模型,开发了模型新的应用方式,采用解析方法计算线路中的雷电感应电压,再通过感应电压分析架空线路受到的影响。实例结合南方电网配电线路实际情况,给出了在安装有架空地线性线和没有安装架空地线的低压系统中雷电感应过电压,感应电流的分布,以及其耐雷水平的计算结果,讨论线路的承受能力以及可能产生的电磁干扰和影响范围。研究了系统中架空线路配置的作用。结果显示架空地线能够大幅提高配电线路对感应雷的耐雷水平,降低闪络概率。该模型被验证能够很好的应用于配网线路的防雷工作。

In this paper,an engineering model method is proposed for calculating lightning induced overvoltage based on a MODELS language.It is used to model the lightning channel and analyze the electromagnetic coupling with the overhead lines,and is implemented and verified in ATP/EMTP.Considering the influence of the consumed ground surface on the radial electric field,this method can build the induced lightning model suitable for the distribution network transmission lines and overhead lines.It adapts the analytical method to calculate the lightning induced voltage of the lines,and then analyzes the influence of the overhead lines with the induced voltage.Combined with the actual situation of distribution lines in South China power grid,the distribution of lightning induced over-voltage and induced current in low-voltage system with and without overhead ground wires are given,so is the calculation results of its lightning resistance level.The bearing capacity of the lines and their possible electromagnetic interference and influence range are discussed.The role of the overhead line configuration in the system is studied.The results show that the overhead ground wires can greatly improve the lightning resistance level of the distribution lines to induce lightning and reduce the flashover probability.The model is verified to be able to be well applied to the lightning protection of the distribution lines.