Demonstration of a modular, repetitive-fired 1/4-MJ PFN for ETC guns

A compact pulse forming network (PFN) storing 1/4 MJ at 16 kV has been assembled and tested to validate its performance as a driver for an electrothermal-chemical (ETC) gun. The PFN features a triggered vacuum gap output switch; shielded inductors at energy density near 10 MJ/m/sup 3/, with low external magnetic fields; 2.5 MJ/m/sup 3/ metallized electrode, PVDF dielectric capacitors; and a computer-based controller. The PFN was repetitively fired at 1/3 Hz in 5-shot bursts. Variability of the output energy over the burst was less than 2%. Energy density for the overall PFN module was 1.2 MJ/m/sup 3/ and the energy transfer efficiency predicted for a 12-module PFN system to an ETC gun-like load was 85%.