High-Voltage Closing Switches Using Vacuum Electric Breakdown for Pulsed-Power Applications

In our previous research, a high-voltage vacuum closing switch has been proposed to synchronize the output pulses delivered from multiple parallel plasma opening switch modules to the load in a scheme of power conditioning of a generator of high-power nanosecond pulses. However, the breakdown voltage for each stage of the closing switch has to be increased to 150-300 kV to make the whole concept feasible. This paper considers experimental research of the electric breakdown of 1-mm vacuum gaps formed between the plane cathode and the sharp high-voltage anode to achieve higher breakdown voltages. Two electrode arrangements described in this paper include a point-to-plane system at 5 kA and a multichannel disk-shaped switch at 50 kA. Both systems were studied at voltages up to 170 kV, current densities up to 5 kAmiddotcm^-2 , and submicrosecond pulse durations. A concept of a new closing switch capable of operating at 3 MV, 50 ns, and 0.3 MA using multiple sharp-anode vacuum gaps stacked in series is proposed on the basis of the research results