The insulation properties of SF6/N2 mixed gas are important for the insulation design of high-voltage equipment such as gas-insulated switchgear (GIS) and gas-insulated transmission line (GIL). However, the influence of temperature on insulation performance of SF6/N2 under alternating current (ac) voltage is rarely studied. In this article, we did gas breakdown experiments with SF6/N2 mixed gas at temperatures changing from −50 °C to 100 °C. The experimental results indicate that the breakdown voltages of SF6/N2 mixed gas increase with the increase in temperature. In order to explain the phenomenon, the three-body attachment process in compressed SF6 is introduced to analyze the electron avalanche process affected by temperature. The streamer and leader discharge criteria are introduced to qualitatively explain the influence of temperature on the breakdown voltages. It is found that the streamer channel radius becomes larger at elevated temperatures, which causes the increase in breakdown voltage.

中文翻译：

---

交流电压下温度对SF₆/N₂混合气体绝缘性能的影响

SF6/N2混合气体的绝缘性能对于气体绝缘开关设备（GIS）和气体绝缘输电线路（GIL）等高压设备的绝缘设计具有重要意义。然而，很少研究温度对交流电压下SF6/N2绝缘性能的影响。在本文中，我们使用 SF6/N2 混合气体在 -50 °C 到 100 °C 的温度范围内进行了气体分解实验。实验结果表明SF6/N2混合气体的击穿电压随着温度的升高而升高。为了解释这一现象，引入压缩SF6中的三体附着过程来分析受温度影响的电子雪崩过程。引入流注和先导放电标准来定性解释温度对击穿电压的影响。发现流注通道半径在升高的温度下变大，这导致击穿电压增加。