论文部分内容阅读
SF6气体具有极强的温室效应,寻找新型SF6替代气体成为国内外学者需要解决的迫切问题.该文研究了CF3I/N2混合气体针-板间隙和球-板间隙在正负雷电冲击电压作用下的绝缘特性,对CF3I及其混合气体在电力设备中的应用具有重要意义.实验结果表明:极不均匀电场与稍不均匀电场下,CF3I/N2混合气体的间隙放电均存在显著的极性效应.在电极间隙为5mm时随着气压的升高还出现了极性反转现象.针-板电极下原本较高的负极性50％击穿电压在气压较低时出现了低于正极性击穿电压的情况,球-板电极下原本较高的正极性50％击穿电压也出现了低于负极性击穿电压的情况.分析表明,CF3I/N2混合气体出现极性效应以及在短间隙下的极性反转是由于电极间隙间空间电荷的迁移和扩散与气压的共同作用造成的.因此,使用CF3I/N2混合气体作为绝缘介质的电力设备应着重考虑不同气压及均匀度下的极性效应及反转问题.“,”SF6 gas has a very strong greenhouse effect,the search for new alternative gas to SF6 has become an urgent case for researchers.This paper studies the discharge characteristics of CF31/N2 gas mixture with needle-plane and sphere-plane electrode under standard lightning impulse,which is important for CF3I and its mixtures applied in electrical equipment.The results show that the discharge characteristics of CF3I/N2 gas mixtures present an significantly polarity effect both in highly non-uniform electric field and slightly non-uniform electric field.When the electrode gap is 5ram,the polarity reversal phenomenon appeared with the increase of gas pressure.The analysis shows that CF3I/N2 gas mixture appears polarity effect and polarity reversal phenomenon in the short gap is due to the migration and interaction of space charge between electrode gaps.Electrical equipment using CF3I/N2 mixtures as insulation medium should seriously consider about polarity effect and polar reversal phenomenon.