Abstract：In this paper, the model of dielectric breakdown in SF6/N2 mixed gas is simulated by using the Matlab programs. This rod-plane model is established considering the distribution of space charge and introducing physical time, based on the fractal theory. The finite element method (FEM) is used to solve the electric field, and particle continuity equations are solved by the flux corrected transport (FCT) algorithm. Moreover, the characteristics of fractal discharge under various scenarios are analyzed, such as different probability exponents, different discharge thresholds, and different percentages of SF6 and so on. The simulation results show that the number of branches and fractal dimension decrease with the increasing of probability exponent and the percentage of SF6. The discharge fractal dimension D of 50%/50% SF6/N2 gas mixture equals to 1.219 2, and the average velocity during the discharge process of streamer propagation is 1.15Mm/s. Moreover, the distributions of charge density in space, electric field alone the axis, and electrons density alone the axis are calculated.
李敏, 汪沨, 许松枝, 陈晓林, 黄墀志, 谢望君. 基于分形理论的SF6/N2混合气体放电仿真[J]. 电工技术学报, 2016, 31(24): 88-95.
Li Min, Wang Feng, Xu Songzhi, Chen Xiaolin, Huang Chizhi, Xie Wangjun. Simulation of Discharge in SF6/N2 Gas Mixtures Based on Fractal Theory. Transactions of China Electrotechnical Society, 2016, 31(24): 88-95.
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