A technique to reduce plasma armature formation voltage (for railguns)

Experimental results from railgun firings using different shapes of initiation foils are presented. These foils have been designed to vaporize into a plasma armature with reduced transient voltages. A design criteria was developed to ensure that all portions of the foil vaporize at slightly different times. Using this approach, a factor of three reduction in the voltage transient during plasma armature initiation has been observed. The impact of the armature voltage transient is discussed, along with a description of design techniques, test conditions, and experimental findings. To quantify the results, a model of current commutation which includes transient armature voltage data was developed. However, the results of the reduced transient voltage spike do not show shorter commutation time.<
>