Four Pulse Drive System for the Beam Induction Cells and Injector for DARHT Axis 2

The proposed drive system allows for the generation of up to four (4) high-quality radiographic pulses along one line-of-sight, having arbitrary pulse spacing (approximately500 ns), using demonstrated technologies. This concept uses a four-pulse drive system to drive both a 16-MeV ensemble of 250-kV, 4-kA induction cells and a four-pulse, 4-MeV injector. The key to this approach lies in the method used to combine four pulses from different generators in a manner that does not compromise the voltage flatness requirement of ± 1%. The induction cells use core material for only a single pulse. A simple reverse bias circuit is used to reset the cores between pulses, and the insulator has been redesigned to withstand the reverse reset voltage. This approach can be installed in stages so that the facility can be used for dual axis radiography while implementing the multi-pulsing capability. A dual double-pulse format has been identified which provides a sequence of two pulses along one line-of-sight within a 2-microsec window. The 2-microsec windows can be separated by arbitrary time intervals of 2- to 10-microsec