Transient Electromagnetic Field Analysis for the Single-Stage Fast Linear Transformer Driver With Two Different Configurations Using the Finite-Element Method and Finite Integration Technique

Fast linear transformer driver (FLTD) is considered to be one of the most prospective technologies for the next generation Z-pinch driver. Our goal is to design a single-stage FLTD with compact construction and output current amplitude of 1 MA. Two different current return configurations of FLTDs are presented: the coaxial outer barrel and 24 separate columns. An equivalent circuit model for the single-stage FLTD with structure parameters obtained from finite-element analysis (FEA) is proposed. Moreover, 3-D numerical models of the single-stage FLTD have been constructed and computed based on the time-stepping finite-element method (TSFEM). However, the TSFEM is both time- and memory-consuming for even a single-stage FLTD. Therefore, the finite integration technique (FIT) in the time domain is implemented for solving the FLTD-related problem. It is demonstrated that output performance such as output current of the two configurations is in good agreement with an experimental prototype for both circuit simulation and electromagnetic (EM) computations. EM-field distribution and output performance of the two structures are also very similar.