Study on Insulation Condition of <SF_6> Gas Insulated Cubicle (GIC)

<SF_6>气体在几个大气压的压力下用于气体绝缘变电站（GIS）。由于GIS的常规压力很高（几个大气压），需要相当昂贵的压力容器，这一事实阻碍了<SF_6>气体绝缘在低额定电压下广泛用于绝缘。气体绝缘柜的出现，使<SF_6>气体绝缘在低电压等级的应用成为可能。本研究的目的是明确GIC的绝缘条件，与<SF_6>空气和气体混合物可以在近大气压力下使用。所得结果可总结如下。1）测量了<SF_6>E/p高达2，000 V &lt;cm^（-1）&gt; &lt;Torr^（-1）&gt;的空气和空气的有效电离系数，这是预测和模拟气体击穿的最重要基本参数。并以实验公式的形式总结。2）测量<SF_6>了均匀场中空气和空气混合物的击穿电压，表明电压在约90%的百分比压力下呈现最大值<SF_6>。3）全面解释本研究获得的结果，GIC可能建议使用约80至100%的百分比<SF_6>压力。

<SF_6> gas is being used in gas-insulated substations (GIS) at pressures of a few atmosphere. Since the regular pressure of GIS is high (a few atmospheres), rather expensive pressure vessels are required, and this fact prevents <SF_6> gas insulation from being widely used for insulation at low rated voltages. The advent of gasinsulated cubicle (GIC) has made it possible to widen application of <SF_6> gas insulation to low rated voltage area. The purpose of the present study is to make clear the insulation condition of GIC with which <SF_6> and air gas mixtures may be used at near-atmospheric pressures. The results obtained may be summarized as below.1) The effective ionization coefficient, which is the most important fundamental parameter for prediction and simulation of breakdown in gases, of <SF_6> and air has been measured for E/p up to 2,000 V <cm^(-1)> <Torr^(-1)> and summarized in a form of experimental formula.2) The breakdown voltage of <SF_6> and air mixtures in uniform fields has been measured to show that the voltage assume maximum values at an <SF_6> percentage pressure of about 90%.3) Interpreting comprehensively the results obtained in the present study, use of about 80 to 100% percentage <SF_6> pressure may be recommended for use for GIC.