电弧模型对500 kV GIS变电站VFTO的影响

Influence of Arcing Model on the Very Fast Transient Overvoltage in 500 kV GIS Substation

在特快速瞬态过电压(very fast transient overvoltage,VFTO)的研究进程中,隔离开关操作过程中电弧重燃与熄弧的等效模型的建立,对VFTO计算结果有着重要的影响。采用ATP-EMTP内建MODELS模块,结合Mayr电弧分析理论,并考虑电弧电流过零熄弧的影响,建立了一种动态电弧模型。将该模型应用于某500 kV GIS电站VFTO计算中,并与另两种模型进行比较,详细分析其特性,结果表明,与简单电弧模型相比,动态电弧模型考虑了弧道电阻动态变化过程,使得VFTO最大幅值减小,在熄弧阶段振荡频率增大。由理论分析可知,在VFTO计算建模中,是否考虑弧道电阻的动态变化过程,对于计算结果有着重要的影响。

In the research process of very fast transient overvoltage （VFFO）, the establishment of an equivalent model which simulates the breakdown and extinction of arc caused by disconnector switching, has great effect on the result of VFTO calculation. A dynamic arcing model is established using the MODELS of ATP-EMTP. The model is based on the arcing analysis theory of Mayr, and takes the influence of arc extinguishing in the point when current reaches zero into consideration. Moreover, taking a 500 kV gas insulated station （GIS） as a calculation example, this paper comparesthe dynamic model with other two models, and analyzes their properties. Since the dynamic model considers the variation of arc resistance, the result shows that VFTO amplitude decreased and frequency in the extinction phase increased ,when compared to the other two conditions. By the theoretical analysis, the dynamic variation of arc resistance is taken into account or not, has important significance for the VFTO simulation result.