Research on Surface Flashover of Vacuum Insulator with High-Voltage Insulation and Wireless Power Transfer Capabilities

The integrated insulator device with multiple magnetic coupling coils provides continuous and stable power supply for online monitoring equipment. Nevertheless, how the introduction of high-frequency magnetic field effects the surface flashover of the insulator is still unrevealed. Based on the surface flashover hypothesis theory in vacuum, finite element analysis (FEA) method was used to simulate the motion trajectory of initial electron near the insulator in different positions and magnetic field configuration, and the insulation performance was studied by analyzing the electron movement under the influence of electric field and high-frequency magnetic field. It is found that the electron with initial kinetic energy will impact the insulator surface at certain positions and magnetic field configurations, resulting in secondary electron emission (SEE) and continuous accumulation of positive charge on the insulator surface. The movement of secondary electrons towards the anode increases the electric field intensity, which promotes the process of secondary electron emission and positive charge accumulation until the formation of flashover along the surface. In other cases, the electron is deflected by the Lorentz force and leave the surface, so as to inhibit the flashover along the insulator surface.