Abstract
The recovery in a spark gap for repetitive switching has been a long research interest. The surface temperature variation of the anode during switching plays decisive role in recovery of spark gap. This paper presents a method to estimate the effect of anode temperature rise and decay on repetition rate of spark gap. By using this method, the behavior of copper and stainless steel materials were studied for a current pulse of 30 kA. During the pulse period of 10 μs, the temperature rise for SS is higher than Copper. After current zero, the anode temperature decays to the vaporization temperature of the material and determines the recovery time of the spark gap. This temperature decay is also verified by a heat transient computational model developed in FEM based software. Simulations has been carried out for different materials including Cu and SS. Some simulations are in good agreement with existing experimental data. The decay time for current pulses 5 kA, 10 kA, 15 kA, 20 kA, 25 kA and 30 kA are estimated. The simulation shows higher decay rate for tungsten and lower decay rate for graphite. Similar trend has been observed for silver and copper. Theoretical analysis of recovery times, heat transfer simulation model for different anode materials are presented and the results are discussed.
Get full access to this article
View all access options for this article.