The voltage polarity and structural design of the pulsed power module are the key factors affecting the dielectric strength. In a vacuum environment, the voltage polarity of the pulse power module is different, and the flashover voltage is also different, and there is a significant polarity effect. After analysis, the cathode field emission and the gas desorption of the insulating material are the main reasons for the surface breakdown voltage of the negative-point positive plate electrode being lower than the surface breakdown voltage of the positive-point negative plate. To verify this conclusion, a needle-plate electrode vacuum breakdown experiment was designed. The internal electric field distribution of the pulse power module was calculated by COMSOL software. At the same time, the module vacuum breakdown experiment was designed. The simulation and experimental results show that the vacuum breakdown voltage of the pulse power supply module can be effectively improved by positively charging the electrode with smaller curvature radius and increasing the curvature radius of the inner electrode of the power supply module.

pulse power supply,discharge in vacuum,polar effect,COMSOL simulation,vacuum insulation