The self-breakdown characteristics of the magnetic delayed pseudospark switch

Abstract

Summary form only given. Pseudospark switches and magnetic switches have developed respectively for decades. But rare effort has been devoted to the combination of them and further, the coupling performances. This paper deals with the self-breakdown characteristics of a magnetic delayed pseudospark switch (MDPSS), which is a pseudospark switch being in series with a magnetic switch. By incorporating the advantages of pseudospark switches and magnetic switches, MDPSS shows great potential in the application o f repetitive pulsed power system. Furthermore, the commutation loss of pseudospark switches and the size o f magnetic switches are significantly reduced. A repetitive pulsed platform, which can generate voltage pulses with the amplitude of 15 kV at the frequency of 50 Hz, was set up. A MDPSS prototype was elaborately designed, o f which the maximum hold-off voltage is ~30kV. With this platform, the operating and conducting characteristics o f the prototype under repetitive pulses were studied. The results showed that, firstly, the conduction delay of the pseduospark switches is hundreds o f microseconds in the first discharge, and about 1μs in subsequent discharges without triggering under 10kV, 50Hz repetitive voltage pulses. The delay and jitter o f the first discharge is much worse than those of the subsequent discharges. Secondly, magnetic switches with suitable volt-second product have great "magnetic delayed" effect which delay the rise of the current flowing through the pseudospark switch, leading to the fact that the hold-off voltage across the pseudospark switch dropped to a pretty low value before the current rose rapidly. This resulted in a great reduction of commutation loss during the switching period o f pseudospark switches. The loss was reduced to 7.5 times lower than before, and could further be reduced in future studies. Meanwhile, magnetic delayed effect was enhanced with the increase o f the volt-second product. Finally, its future applications are discussed. Self-breakdown characteristics o f MDPSS not only are the preliminary researches for the triggered ones, but also have significant applications, like the synchronization o f multistage Marx generators. MDPSS shows great repetitive performances and have substantial potential to become the main switches in pulsed power technology.