Component design, development, and testing of an inductive voltage adder (IVA) system for Jupiter
Jupiter is a proposed 15-20 MJ laboratory X-ray source. It would store /spl sim/100 MJ in the Marx generators and deliver /spl sim/500 TW to drive high power z-pinch implosions. The pulsed power requirements for Jupiter were evaluated by a national review panel which concluded that the modular IVA technology as used in HERMES III is capable of meeting these requirements. Modularity of construction permits design verification with less than a full size system and offers the flexibility to meet changing requirements. A program to validate this approach at the required power levels has begun with the construction and testing of components that will comprise a full scale IVA generator module. The IVA module will provide a nominal 10 MV, 1.8 MA, 100 ns FWHM output pulse and will consist of four submodules. Each submodule is composed of a Marx generator, two intermediate energy storage capacitors (ISCs) four pulse forming lines (PFLs), one voltage adder cavity (VAC), plus other associated switches and hardware. A conceptual design for this IVA module has been completed. Initial designs for the ISC, PFL, and their gas switches are also complete and hardware has been procured. Testing of these components is underway at Sandia National Laboratories. Discussions of these designs and results of tests are presented in this paper.
Double-Bounce Switching
Abstract : Double-bounce switching is a technique for exploiting traveling waves in a transmission-line-type pulse forming system to reduce voltage requirements on pulse forming line (PFL) output switches. If a simple PFL (a de charged ideal transmission line with characteristic impedance Z) is switched into a matched load, then peak output power is v2/4Z, where V is output switch voltage. If the PFL is pulse-charged by another transmission line, and if geometries, circuit parameters, and switch points are chosen properly, then the PFL can inject a power much larger than v2/4Z into a matched load. This is the principle of double-bounce switching (so called because it exploits a doubly reflected charging wave in the PFL). Data from EAGLE experiments are presented which demonstrate that the technique works in a real geometry.
Indented-anode diode for HERMES III
Design of three diode configurations that meet the radiation goals of HERMES III and calculation of associated radiation outputs are discussed. These goals are to produce a 20-ns FWHM radiation pulse having a peak dose rate of 5 x 10/sup 12/ rad(Si)/s with a variation of less than a factor of two over a 500 cm/sup 2/ irradiation area, to keep the variation less than a factor of four over the irradiation volume defined by extending the area downstream by 15 cm, and to maintain a minimum dose rate over this volume in excess of 2.5 x 10/sup 12/ rad(Si)/s.