Effect of the External Transverse Magnetic Field on the Breakdown of Vacuum Gap between Rod-Plate Electrodes

The objective of this paper is to study the influence of the external transverse magnetic field on the breakdown of vacuum gap between rod-plate electrodes. Firstly, the electric field distribution of the rod plate electrode and the magnetic field distribution generated by the permanent magnet were simulated. Then, the effect of applying a transverse magnetic field on the vacuum gap field emission current of the rod-plate electrode was experimentally studied. The experiment was conducted under some small electrode gaps, and the field emission current measured under the same voltage at different gaps was used for horizontal comparison to analyze the effect of the transverse magnetic field. The simulation and experimental results suggest that, the magnetic fluid density generated in the center area of the electrode is higher when the permanent magnets are arranged in a surround pattern than when they are arranged in a straight pattern. In addition, the effect of applying a magnetic field on the field emission current is not significant at a gap distance of d = 0.5 mm. However, at a gap distance d = 0.8 mm, the amplitude of the field emission current with applied transverse magnetic field decreases by an average of 39.53% compared to without applied transverse magnetic field.