Design and operation of a self activating crowbar switch

A simple and reliable crowbar switch has been designed and successfully used in the electromagnetic propulsion research program at Materials Research Laboratories. The switch is self activating and has crowbarred a 6211 μF, 8 kV capacitor bank at peak currents in excess of 220 kA. It is manufactured from readily available components and suffers little damage during switching. This paper describes the switch design, and presents results of the crowbarred capacitor currents and voltage. Possible modifications for improved performance are discussed.