Inductive voltage adder accelerator architectures for radiographic applications

The RITS-3 accelerator [1] at Sandia National Laboratories has served as an inductive voltage adder test bed for pulsed power and power flow development and testing as well as for radiographic diode research and development. Several key pulsed power and power flow issues were identified as elements to be changed or modified if the basic RITS architecture were to be used for practical radiographic accelerators. Methods of prepulse reduction, better synchronization of switching, more compact arrangements of the pulsed power components were some design changes identified. The impedances of the pulse forming networks can be increased and hence store less energy if the sheath current flowing in the magnetically insulated transmission line (MITL) can be re-trapped [2] as opposed to being lost. Designs of accelerators with voltages from 2 MY to 14 MY will be examined to provide examples of how unique sets of requirements can drive the device configuration. Higher voltages are achieved by simply adding more inductive cavities. The inductive cavities also allow positive polarity output without changing the basic pulse forming network polarity. This versatility allows a single accelerator to drive diodes requiring either positive or negative polarity pulses.