Experimental study and performance analysis on high gradient insulators

High gradient insulators (HGIs) were developed to solve the vacuum surface flashover problem in pulsed power system. The vacuum out-gassing rate and desorption gas components of HGIs were measured using an all-metal ultrahigh-vacuum analysis system. The high frequency dielectric constant was measured by impedance analyzer. Based on the nanosecond pulsed experimental platform， the vacuum surface flashover characteristics of HGIs were tested. The results indicate that HGIs have good high frequency dielectric performance with the inflection frequency up to 200 MHz and the flashover field strength is about 190 kV/cm after 30 discharges. The flashover performance of HGIs has direct relation to the insulation layer materials and the ratio of insulation layer and metal layer.