Influence of Gas Pressure and Gap Distance on the Recovery Time of Gas Spark Gap Switch

The recovery characteristics of gas spark gap switch applied in a high power water dielectric pulse forming line with different gas pressure and gas gap distance are experimentally studied using a two-pulse method.The recovery times of gas switch breakdown voltage were given.The results show that as the working pressure(such as 0.5 MPa,1 MPa,1.5 MPa,2 MPa)of gas switch increases,the recovery time of gas switch increases from 50ms to 78ms.The influence of gap distance of electrodes on the recovery time was also experimentally studied.At the gap distance of 7.3 mm and 27.4 mm,experimental results show that the influence on the recovery time is not remarkable.The experiments also prove that the repetitive rate of high power accelerator with pulse forming line is mainly restricted by the gas switch repetitive rate,and the recovery percentage of the vacuum diode voltage and gas switch breakdown voltage are consistent.The method for improving the recovery time is introduced such as using the gas switch with the gap distance smaller than mm level,or making the switch worked at the flat part of the U/p curve.