Design and code validation of the Jupiter inductive voltage adder (IVA) PRS driver

Abstract

The proposed Jupiter accelerator is a -10-MV, 500-TW system capable of delivering 15-MJ kinetic energy to an imploding plasma radiation source (PRS).lS2 The accelerator is based on Hemes-1113 technology and contains 30 identical inductive voltage adder modules connected in parallel. The modules drive a common circular convolute electrode system in the center of which is located an imploding foil. The relatively high voltage of 8-10 MV is required to compensate for the voltage differential generated across the load due primarily to the fast increase in current (L Wdt) and to lesser extent to the increasing inductance (I dL/dt) and resistive component of the imploding foil. Here we examine the power flow through the device and, in particular, through the voltage adder and long MITL. Analytical models, such as pressure balance and parapotential flow, as well as circuit and PIC codes, were utilized. A new version of the TWOQUICK PIC4 code, which includes an imploding, cylindrical foil as load, was utilized to compare the power flow calculations done with SCREAMER5 and TRIFL.6 The agreement is very satisfactory and adds confidence to the Jupiter design. In addition, an experimental validation of the design is under way this year (FY95) with Hemes III. Long extension MITLs are connected at the end of the voltage adder with inductive and diode loads to benchmark the above design codes. In this paper we outline the accelerator's conceptual design with emphasis on the power flow and coupling to the inductive load and include preliminary results of Hemes-111 experimental design validation?

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