The self-breakdown voltage of pseudospark switches

In order to develop a high hold-off voltage (over 60 kV) pseudospark switch (PSS), the parameters which affect the hold-off voltage such as the working gas, the pressure, the gap distance and the hole diameter of the electrodes etc. have been studied. The experiment results show that helium is a best choice as the working gas; the hold-off voltage inverses with two gap distance of the electrodes and the diameter of the hole on the electrodes. A new type of two stage PSS which possesses a hollow intermediate electrode has been developed. The self-breakdown curve of the improved two-stage PSS is shifted to higher pressures corresponding to that of the one-stage PSS and the ordinary two-stage PSS which possesses a plane intermediate electrode. Then it can operate at higher voltages. With the same condition, the erosion caused by discharge on the electrodes can be lowered and the lifetime is prolonged.