低SF_6含量混合气体电晕放电特性仿真研究

2-D Corona Simulations of Low SF_6 Content Mixtures

低SF6含量混合气体绝缘介质最有可能替代SF6气体应用于气体绝缘设备中。本研究采用有限元-通量校正传输(FEM-FCT)法求解低SF6含量的SF6/N2混合气体二维流注电晕放电的数学模型,考虑了空间电荷对场域的畸变作用,研究了SF6/N2混合气体二维流注电晕的放电特性,展示了流注电晕放电发展过程中间隙内部各种带电粒子浓度和空间电场的分布。仿真表明:棒-板间隙中空间光电离对流注电晕发展的影响强于阴极光发射;外施电压幅值小时,流注形成和发展速度较慢,流注电晕相对稳定。

Finite element method-flux corrected transport technique （FEM-FCT） is used to solve the continuity equations for electrons, positive ions, and negative ions to analyze streamer corona dis- charge mechanism in low SF6 content mixtures, which is the most promising substitute for SF6 in gas insulated switchgear. Electric field distortion caused by space charge is taken into account. The corona discharge mechanism in SF6/N2 gas mixtures is researched in this paper, the densities of dif- ferent particles and the electric field distributions in the discharge process of streamer corona are described. Results show that the effect of photoionization is stronger than photoemission, and the streamer corona discharge becomes relatively stable with the applied voltage decreasing.