The influence of the gas insulation parameters on the three-electrode spark gap functioning

Abstract

The influence of the gas insulation parameters on the three-electrode spark gap functioning is considered in this paper. Two types of three-electrode vacuum and gas insulated spark gaps have been tested: a spark gap with a third electrode being inside the main electrode, and a spark gap with a separate third electrode. Both types of spark gaps were theoretically sized in the optimal way by computer prediction. In order to investigate the influence of insulation parameters on the spark gap functioning, type of gas and electrode material have been tested. Beside vacuum, applied gases were: SF/sub 6/, and N/sub 2/. The electrode materials were copper, tungsten and steel. The investigation was done by determining the points switching time-working voltage under constant values of the other parameters. The working voltage value was taken as a changeable parameter during measurements. During each test, 60 values of flashover voltage of both polarities were measured. After that, the spark gap delay time or switching time was measured. In order to obtain the single point delay time-working voltage or switching time-working voltage, a series of 50 measurements was accomplished. Also, 1000 triggerings have been accomplished without a change of gas and electrodes in order to test the reversibility characteristics of spark gaps by measuring of switching time.