冲击电压下CF_3I/CO_2混合气体间隙的绝缘特性与极性效应

广泛应用于电力系统的SF_6气体是一种强温室效应气体,寻找新型环保型替代气体成为电力行业亟待解决的问题。为此文中对体积比为3:7的CF_3I/CO_2混合气体进行了实验研究,测量了雷电冲击电压下CF_3I混合气体的50%击穿电压,并和纯SF_6气体的绝缘性能进行了比较。结果表明:CF_3I/CO_2具有较好的绝缘能力,在稍不均匀电场下可以达到SF_6气体绝缘强度的0.84倍,在极不均匀场下也可以达到SF_6气体的0.65倍。还对CF_3I/CO_2混合气体的极性效应进行了分析,结果显示极不均匀场下的CF_3I混合气体极性效应更加明显,并且还出现了极性反转现象。

Insulation Property and Polarity Effect of Gas Gap of CF_3I/CO_2 Mixture Under Impulse Voltage

SF6 gas has been widely used in power system, however, it has a strong greenhouse effect. Looking for new environmentally friendly alternative gas becomes an urgent task for the power industry. Therefore, we experimentally investigated the CF3I/CO2 gas mixture with a mixing ratio of 3:7. The 50% breakdown voltage of the CF3I gas mixture under lightning impulse was measured and compared with pure SF6 gas. The results show that the CF3I/CO2 mixture has good insulation properties, its insulation strength can reach 0.84 times of SF6 gas under slightly uneven electrical field, and 0.65 times of SF6 gas in extremely inhomogeneous electrical field. The polarity effect of the CF3I/CO2 gas mixture was also analyzed. The results show that the polarity effect of the CF3I gas mixture in extremely inhomogeneous electrical field is more obvious, and the phenomenon of polarity reversal occurs.