Experimental investigation of POS

The performance of a plasma opening switch (POS) was studied, experimentally using a nanosecond pulsed power generator (600-800 kV, 40-60 ns) as well as a small capacitor bank (20 kV, 15-20 kA, 0.25-1 μs). It was shown that the initial stage of POS action is related to the formation of the cathode plasma. The reproducibility of results is related to that of the cathode plasma light emission pattern. Switch opening occurs at any load, and the increase of POS resistance weakly depends on that of the load. The physics of opening is related mainly to some internal mechanisms. It was shown that a partially neutralized high-current electron beam directed to the load is formed at the final stage of switch opening. The appearance of this beam in the downstream coaxial structure or in the load diode limits the open POS impedance and explains the reported effect of decreased diode impedance that occurs even for large anode-cathode gaps