Microsecond conduction time POS experiments

摘要

The plasma opening switch operation (POS) was studied by optical diagnostics, such as laser interferometry and spectroscopy. The characterization of the plasma source (cable plasma gun) allowed us to determine initial plasma conditions for the switch. The process of the vacuum gap formation in a microsecond plasma opening switch was also investigated. Time- and spatially-resolved density measurements are performed in the POS, showing the density drop during switch-opening almost in the whole interelectrode gap. The density diagrams are compared to major switch characteristics, such as conduction time and load current dI/dt. The study of spectral line intensities from the cable gun plasma showed that CII line intensity corresponds in time with plasma density measured by an interferometer. The intensities of carbon spectral lines tend to drop during switch-opening that substantiates interferometry measurements.