Characterization of a 30 kV, 75 C triggered vacuum switch

We designed, fabricated, and tested sealed-off triggered vacuum switches (TVSs) used as an ETC-gun switch. To fabricate the sealed-off TVS, we developed fabrication processes. The TVSs were successfully tested up to 30-kV peak charging voltage, 109-kA peak current, 1.5-ms current pulse-width, and 75-coulomb integrated charge transfer. Compared to other reported similar switches, the tested switch showed high trigger reliability. This was realized by the unique fabrication process we developed. The TVS also shows high electrical characteristics in terms of operating voltage and current, charge transfer, and pulse length. Rectifying characteristics of the switch were also investigated. We found that the tested TVS had a specific area to have the diode phenomena. The area was defined by the rate of current decay and also the rate of reverse voltage rise. The defined area somewhat varies depends on circuit conditions. However, the tested TVS acted as a diode if the rate of current decay was less than 10 kV/μs, and the rate of reverse voltage rise was less than 230 A/μs.