Experimental Study of the Voltage Recovery Characteristics of Spark Gap Switch with Different Gases

Summary form only given. The recovery characteristics of a gas spark gap switch applied in a high power water dielectric pulse forming line with different gas types are determined using a two-pulse method. Under the breakdown voltage of 450 kV (the vacuum diode voltage is about 200 kV) and current 30 kA, the recovery characteristic of H₂, N₂, SF₆ have been studied. The recovery percentages of gas breakdown voltage and vacuum diode voltage are given. The results show that hydrogen has the best recovery characteristic. At a pulse interval of 8.8 ms, the recovery percentages of both gas breakdown voltage and vacuum diode voltage exceed 95%; for SF₆, N₂ with the interval of 25 ms and 50 ms, 90% voltage recovery percentages are obtained. The experiments also prove that the repetitive rate of high power accelerators with pulse forming lines is mainly restricted by the gas switch repetition rate; the recovery percentages of the vacuum diode voltage and gas switch breakdown voltage are consistent; a hydrogen switch can be used for a high repetition rate, high power accelerator with a pulse forming line.