Simulation on Initial Development of Surface Streamer in SF6 Gas Environment

The concentration of electric field at gas-solid interface might cause flashover along the surface. The streamer development significantly affects the initial flashover process along the surface and is worthy of theoretical study. In this paper, the initial development characteristics of surface streamer in SF6 gas environment are studied by simulation. The influences of the uniformity of the positive electric field and the dielectric constant of the dielectric-material and the electron distribution characteristics are investigated. The results show that a large number of electrons (1023) will accumulate at the tip of the positive electrode in the surface streamer, and the relative electron peak is formed at the head of the streamer. The more uniform the positive electric field is, the later the initial development time of the streamer is, and the faster the streamer is. When the dielectric constant of the interface material increases, the streamer will develop in advance and speed up, and the electron density of the head and channel of the streamer will decrease.