Fuse and load testing with mid-sized, high energy density flux compression generators

Compact Pulsed Power Systems (CPPSs) require power sources that are small in size yet can produce the necessary electrical energy required to drive a given load. Helical Flux Compression Generators (HFCGs) are attractive for single shot applications due to their rapid conversion of chemical energy to electrical energy. Mid-sized generators occupy little total volume (∼4,000-cm³ total with a compressible volume of ∼300-cm³ in the present generator design), while the high explosives used in an HFCG provide an energy density of ∼8,000 MJ/m³. Consistent output current and energy gain from shot to shot are key variables in the ability of an HFCG to drive CPPSs effectively. An investigation into the practicality of using mid-sized HFCGs as the driver for single shot CPPSs is presented. Data and waveforms from generators fired into 3 μH inductive loads are shown, with results measuring the generator’s performance as a driver for an inductive energy storage (IES) system. Results are also shown from adding a power conditioning system to the output of the HFCG, where the measurements demonstrate the ability of an HFCG to drive high impedance loads. The effectiveness of a mid-sized HFCG as drivers for these systems will be evaluated.

I. Introduction

HFCGs have been used as high current/high magnetic field sources since the 1950’ s. Systems powered solely by an HFCG can be limited by several factors. One factor is that small to mid-sized generators have been known to suffer from inconsistent output for successive shots [1]. One solution for this problem is to employ a construction technique which minimizes deviations in the generator characteristic parameters from one generator to the next. An HFCG design, fabrication technique and initial performance measure were outlined in [2] and [3], with the aim of increasing long term generator consistency. This paper provides more analysis on the consistency of generator performance for successive shots.