Improved operation of microsecond plasma opening switch by plasma source modification

摘要

The characteristics of a microsecond plasma opening switch have been improved by the modification of the plasma source. Conventional cable plasma guns have been used in the experiments, producing different directions of the plasma flow by changing the guns' nozzles. The nozzles were arranged to provide the plasma flow, which is not exactly radial, but has an angle to the gun axis. The experiments with the modified plasma guns were carried out with the upstream, downstream, and azimuthally slanted plasma flow directions. The results are compared to a conventional radial flow plasma source. The plasma flow slanted in an angle of 30 degrees downstream resulted in 50% improvement of the load current rise time and switch impedance. The obtained dependencies are explained in the frame of the snowplow model. Radial component of the plasma velocity at the end of the conduction phase is higher for downstream plasma flow. This results in a faster opening of the switch and is in good agreement with experimental data. (C) 1999 American Institute of Physics. [S1070-664X(99)02808-6]. [References: 23]