小电流接地故障电弧建模分析

Modeling Analysis of Arc Grounding Fault in Non-solidly Earthed System

在小电流接地系统中单相电弧接地故障普遍存在,建立准确的电弧模型是研究故障特征的基础。本文在经典"控制论"电弧模型的基础上建立了改进的"控制论"电弧模型,通过控制弧长可以准确地模拟小电流接地故障电弧的发展过程。基于PSCAD平台搭建了典型10 kV配电网仿真模型和接地电弧模型,分析了不同电弧模型参数对电弧特性的影响。仿真与实测结果基本一致,表明该电弧模型能够有效反映接地电弧特性,通过改变模型参数可以实现不同类型电弧的仿真模拟。

The single-phase arc grounding fault frequently occurs in non-solidly earthed systems,and the establishment of an accurate arc model is the basis for studying the fault characteristics.In this paper,based on the classical cybernetic arc model,an improved cybernetic arc model is built at first,which can accurately simulate the arc development process in the non-solidly earthed system through controlling the arc length.Then,a simulation model of a typical 10 kV distribution network and a grounding arc model are built on the basis of the PSCAD platform,and the influences of different arc model parameters on arc characteristics are analyzed.Simulation results basically agree with the field data,indicating that the proposed arc model can effectively reflect the grounding arc characteristics and the simulation of different types of arc can be realized by altering the model parameters.