100 kV capacitor development for fast Marx generators

Fast Marx generators (FMG's) are being developed as an affordable approach to 50 MA PRS drivers and as options for upgrading existing pulse power drivers (e.g. Decade & Double-EAGLE). FMG designs conceptualized in a DTRA sponsored power flow study are based on the integration of new flat, wide capacitors coupled to rail gap switches. This results in a short Fast Marx stage discharge time ((LC)/sup 1/2/ < 300ns) and low stage impedance ((LC)/sup 1/2/ < 0.5Q) with high current capability (I/spl cong/250kA). General Atomics Energy Products developed a 1.35/spl mu/F, 100 kV, 2.6/spl times/24/spl times/38" plastic case capacitor with rails terminals along each end for this application. Titan integrated two such capacitors with a rail gap switch to create a FMG stage. This configuration resulted in Marx stage inductance <100 nH. Prototype Marx's up to four stages have been successfully tested. This paper describes the FMG capacitor, its basic design and presents performance test data. Further developments to resolve manufacturing issues and to reduce cost are also discussed.