CF_3I-CO_2混合气体在针板电极下局部放电绝缘特性实验研究

Experimental Study of Partial Discharge Insulating Properties for CF_3I-CO_2 Mixtures under Needle-Plate Electrode

由于SF6气体严重的温室效应影响,减少或杜绝SF6气体的使用已经达成共识,有关SF6替代气体的研究围绕一种电负性气体和缓冲气体的混合气体展开。本文在针板电极下通过工频实验同时测量了CF3I-CO2的局部放电起始电压和击穿电压,讨论了混合比、压强对混合气体局部放电性能的影响,并与SF6-CO2混合气体的局部放电起始电压进行比较。实验结果表明:一个大气压下,纯CF3I的击穿电压是SF6的1.2倍;CF3I-CO2的局部放电起始电压是SF6-CO2的0.9～1.1倍,同时,CF3I气体与CO2气体具有很好的协同效应,协同效应值为0.53;CF3I-CO2(30%-70%)混合气体的局部放电能力是纯SF6的0.74倍。因此,从局部放电性能的角度来看,CF3I-CO2(30%-70%)混合气体有可能替代SF6气体用在气体绝缘设备中。

As the greenhouse effect of SF6 gas,it has become a common view that less or no SF6 gas would be used in future,and many studies have been carried out recently on gas mixtures composed of a small amount of electronegative gas and a buffer gas.This paper measured the partial discharge initial voltages and breakdown voltage of CF3I-CO2 mixtures under needle-plate electrode with 50Hz ac high voltage and compared that with SF6-CO2 mixtures,and analyzed the effect of mixing ratios,gas pressures on the partial discharge initial voltage of CF3I-CO2 mixtures.The experimental results show that the breakdown voltage of pure CF3I gas is about 1.2 times of that of SF6 gas in 0.1MPa;the partial discharge initial voltages of CF3I-CO2 mixtures are about 0.9～1.1 times of that of SF6-CO2 mixtures,and the favorable synergistic effect is observed between CF3I gas and CO2 gas,the synergistic factor is about 0.53;the partial discharge initial voltages of CF3I-CO2(30%-70%) mixtures are about 0.74 times of that of SF6 gas.Consequently,from the point of partial discharge performance,CF3I-CO2(30%-70%) mixtures can be considered as SF6 substitute used in gas-insulated power apparatus.