250 kA compact linear transformer driver for wire arrayz-pinch loads

S C Bott,K Struve,U Ueda,J Peebles,K Gunasekera,R Sharpe,F N Beg,D M Haas,R E Madden,G Collins,D Mariscal,M Mazarakis,Y Eshaq

doi:10.1103/physrevstab.14.050401

Abstract

We present the application of a short rise ($\ensuremath{\sim}150\text{ }\text{ }\mathrm{ns}$) 250 kA linear transformer driver (LTD) to wire array $z$-pinch loads for the first time. The generator is a modification of a previous driver in which a new conical power feed provides a low inductance coupling to wire loads. Performance of the new design using both short circuit and plasma loads is presented and discussed. The final design delivers $\ensuremath{\sim}200\text{ }\text{ }\mathrm{kA}$ to a wire array load which is in good agreement with SCREAMER calculations using a simplified representative circuit. Example results demonstrate successful experiments using cylindrical, conical, and inverse wire arrays as well as previously published work on $x$-pinch loads.

Highlights

The development of linear transformer driver (LTD) technology [1,2,3] for generating short, high current pulses represents a significant advance in the pursuit of the z-pinch-driven approach to inertial fusion energy (IFE) [4,5,6,7]
This design eliminates the need for large volumes of insulating oil and water which is required for present Marx bank driven generators, and a single compact unit can deliver significant current (> 1 MA)
This is achieved by the parallel discharge of capacitors arranged around a central electrode, with the capacitance and internal inductances of the capacitors themselves determining the output rise time, rather than the use of water-insulated pulse-forming lines

Summary

INTRODUCTION

The development of linear transformer driver (LTD) technology [1,2,3] for generating short, high current pulses represents a significant advance in the pursuit of the z-pinch-driven approach to inertial fusion energy (IFE) [4,5,6,7] This design eliminates the need for large volumes of insulating oil and water which is required for present Marx bank driven generators, and a single compact unit can deliver significant current (> 1 MA). This is achieved by the parallel discharge of capacitors arranged around a central electrode, with the capacitance and internal inductances of the capacitors themselves determining the output rise time, rather than the use of water-insulated pulse-forming lines.

LTD CAVITY CONFIGURATION AND OPERATION

CONICAL POWER FEED AND EXPERIMENTAL CHAMBER DESIGN

SHORT CIRCUIT TESTING

WIRE ARRAY LOAD RESULTS

SUMMARY