The characteristics of a microsecond plasma opening switch have been improv
ed by the modification of the plasma source. Conventional cable plasma guns
have been used in the experiments, producing different directions of the p
lasma flow by changing the guns' nozzles. The nozzles were arranged to prov
ide the plasma flow, which is not exactly radial, but has an angle to the g
un axis. The experiments with the modified plasma guns were carried out wit
h 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% im
provement of the load current rise time and switch impedance. The obtained
dependencies are explained in the frame of the snowplow model. Radial compo
nent of the plasma velocity at the end of the conduction phase is higher fo
r downstream plasma flow. This results in a faster opening of the switch an
d is in good agreement with experimental data. (C) 1999 American Institute
of Physics. [S1070-664X(99)02808-6].