Improved Output Current Rise Time From Modified Helical Flux Compression Generators

Flux compression generators (FCGs) are widely used to generate extremely high power pulses. When a peak current from a seed source is flowing through the generator circuit, the chemical energy of high explosives is used to increase the amplitude of the output current pulse applied to the load. During the transfer of explosive energy to the output electrical pulse, the critical issue is achieving a change in the inductance in a fast and controlled way. There have been many significant experiments on different kinds of FCGs, and almost all of the theoretical models used to describe generator behavior are based on empirical equations. In this paper, simultaneous detonic, electromagnetic, and circuit simulations are used to study the characteristics of helical FCGs. For this purpose, the magnetic field diffusion and losses due to the induced currents in metallic components are considered in more detail. Based on the results of these theoretical considerations, new modifications for the FCG are proposed. It will be shown that the proposed modified FCG geometries yield output current rise times that are about 60% of those achieved with conventional helical FCGs generating the same current pulse amplitudes.