Characterization of Runtime and Jitter on a Laser Triggered Spark Gap Switch

Summary form only given. A 1 MV, SF₆ filled, laser triggered gas switch has been installed on the University of Missouri pulsed power test stand to study the factors affecting runtime and jitter. The test stand consists of a 2.8 MV, 450 kJ Marx bank that feeds into a 7 nF intermediate store capacitor before discharging through the gas switch. The test was operated from about 1 MV up to 2.5 MV, at switch pressures from 1 to 4 atm. The gas switch is triggered by a 30 mJ New Wave Tempest 10 Nd:YAG laser to initiate breakdown in the switch. The University of Missouri has examined factors including the applied field, rate of rise and gas pressure of the switch along with the laser power, focused intensity, and Rayleigh range and determined their relation to jitter and runtime. Optical spectroscopy has been used to examine both the laser arc and the resulting switch discharge plasma parameters and composition. The end goal of research is to understand the factors contributing to increased jitter and runtime and thereby provide paths to improved switch performance.