Improvement of the Energy Coupling to Low-Impedance Loads using Flux Extruders (Current Multiplier) on Existing Pulse-Power Generators

Abstract

Summary form only given. The current multiplier (CM) concept was proposed to increase the driver-to-load energy transfer efficiency. The usual pulse-power load may have the inductance substantially lower than that of the generator, The suggested CM requires additional volumes with high self-inductance (magnetic flux extruders). Toroidal flux extruders can be incorporated into the vacuum part of existing pulse-power generator prior to the load and they extrude the magnetic flux toward the load magnifying the load current. Recent experiments with one extruder confirmed the concept at MA load currents with microsecond rise time both in static load inductance and in a dvnamic load (z-pinch). The accumulated experience in practical multiplier designs for high impedance generators suggests experiments to evaluate the performance of this new device on low-impedance nanosecond MA generators used for radiation production with z-pinches and for material studies in isentropic compression experiments (ICE). In this work, we present the optimization procedure for two existing generators, Saturn of Sandia and Zebra of Nevada TF operating with one or two extruders. The procedure allows comparison of the energy transfer efficiencies for different geometrical arrangements of extruders in a CM and design of the corresponding hardware in concrete experiments. Analytical and numerical study performed for these facilities suggest that better generator-to-load energy coupling is possible for both z-pinch and ICE loads. Available experimental results for some realistic CM hardware configurations will be also presented.