Investigation of the Dielectric Properties of the Insulating Gas of Commercial Gas-Filled Surge Arresters

Based on the experimental results of dynamic breakdown voltage and electrical breakdown time delay, the dielectric properties of insulating gas commercial gas-filled surge arresters (GFSA) were analyzed. Data for dynamic breakdown voltage obtained by the method of stepwise increase of voltage whose rise rates ranged from 1 to 10 V/s. It is shown that these values of voltage rise rate do not have a significant effect on the value of dynamic breakdown voltage. In order to monitor the processes caused by electrical breakdown on the dielectric properties of insulating gas of these components, the electrical breakdown time delay was a measure for different values of relaxation time and applied voltage. It has been shown that the presence of positive ions, which are formed during breakdown and subsequent self-sustaining discharge with recombination time of about 1 ms, has a significant effect on the reduction of the dielectric resistance of insulating gas. It has also been shown that the applied voltage whose values are close to dc-spark over-voltage has a significant effect on the delay response of these components.