Development of Switching Components for Controlled-Fusion Research

Needs and applications for ultra-high-power switching are discussed, and various approaches are compared. Capacitor-bank experience and circuitry are covered, together with ignitron limitations. A test and cooperative development program has led to: (a) a 2 inch 10 kv ignitron for 30 kamp for 500 μsec; and (b) a 4 inch insulated-cathode ignitron for 10 kamp for 20 msec. Times for arc transfer to the wall are given for the 5 inch 5555 ignitron. A radical 19 inch flat ignitron has been built, and a 40 kv 200 kamp fast mechanical switch is being developed. Firing delay and jitter are given for the 2 inch ignitron.