Empirical modelling of copper foil fuses [as pulsed power switches]

This paper describes experiments that use a fast capacitor bank to provide data for the production of simple but accurate empirical models for exploding copper foil fuses. It is demonstrated that foils of different thicknesses behave quite differently, a phenomenon previously noted only for exploding aluminium foils. Empirical models for both 17 /spl mu/m and 25.4 /spl mu/m foils were developed from the experimental data, and used successfully in computer programs which predict in detail the behaviour of the foils in a variety of switching circuits. The computer models were used to optimise the design of an exploding foil used as an opening pulsed power switch in a capacitor driven circuit, that transfers a sharp current pulse to a plasma erosion opening switch (PEOS). It was predicted that voltages exceeding six times the initial bank voltages could be produced, and experiments are described that provide evidence for this while avoiding the possibility of damage to the bank.