This paper provides a comparative study on the impulse breakdown performance of SF 6 and 20% C 3 F 7 CN / 80% CO 2 gas mixture under weak non-uniform electric fields. Two geometrically distinct electrode configurations, with similar field utilization factor, were subjected to standard lightning impulse waveform (1.2/50 μs) and the effects of pressure, gap distance and impulse polarity on breakdown characteristics were studied. The results show that SF 6 has a higher breakdown voltage than the C 3 F 7 CN/CO 2 mixture and the positive 1.2/50 μs breakdown voltages were found to be higher than the negative counterparts. These results show that the effect of polarity on breakdown voltage does not exclusively depend on electrode geometry but also on pressure and gas type. The results of this paper identify the weaker polarity for 20% C3F7CN / 80% CO2 tested with hemispherical rod-plane and coaxial electrode configurations and the results contribute to the design of SF 6 -free gas insulated equipment.

中文翻译：

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用于研究电磁波发射的氧气负电晕新粒子模型

本文对SF 6 和20% C 3 F 7 CN / 80% CO 2 混合气体在弱非均匀电场下的脉冲击穿性能进行了对比研究。具有相似场利用系数的两种几何不同的电极配置受到标准雷电脉冲波形（1.2/50 μs）的影响，并研究了压力、间隙距离和脉冲极性对击穿特性的影响。结果表明SF 6 具有比C 3 F 7 CN/CO 2 混合物更高的击穿电压，并且发现正1.2/50 μs击穿电压高于负对应物。这些结果表明极性对击穿电压的影响不仅取决于电极几何形状，还取决于压力和气体类型。