Laser triggering of a 500-kV rail-gap switch

Publisher Website
Google Scholar
Abstract
Laser triggering of a SF6‐filled, 500‐kV rail gap is described. A softly focused KrF laser beam was employed to irradiate insulator SF6 gas through the rail gap along a 60‐cm‐long, high‐voltage electrode with the power level of 5×107 W/cm2. The rail gap was operated as the main switch of a 2.8‐Ω, 500‐kV Blumlein circuit, two of which drive the electron beam diodes to pump a 200‐J, 70‐ns KrF laser from both sides. Multichannel operation of the rail gap was obtained by the application of laser triggering with the result of reduced voltage fall time of 20 ns (10–90%) compared with 50 ns in the self‐breakdown mode. The jitter was also decreased to less than 2 ns in the trigger operation of the gap.