The influence of surface charge accumulation on the vaccum surface flashover characteristic of epoxy resin under nanosecond pulse

The vacuum surface flashover characteristic of solid material under steep pulse severely restricts the structure and performance of pulsed-power devices; and with excellent performance in insulation and mechanical strength, epoxy resin has been widely employed in pulse equipment; moreover, the accumulation of surface charge not only enhances the electric field but also affects the movement of the charge produced during flashover as to influence the flashover voltage, so the study of vacuum surface flashover characteristic and surface charge property of epoxy resin under steep pulse is of great significance. Using the 15 ns/1070 ns (referring to the rise time and the half-height width time of the pulse) single-pulse generator, remaining the vacuum on the level of 5E-3Pa, the surface flashover voltage of epoxy resin at different flashover times are tested in this article, and applying a tridimensional regulating mechanism and a surface potentiometer, the surface charge distribution after certain flashover times is measured at the meantime under the same vacuum degree. Via injecting surface charges in different polarize and magnitude to epoxy resin sample, the article studies the function mechanism of surface charge accumulation on the vacuum flashover voltage of epoxy resin under steep pulse.