Development of nanosecond repetitive pulsed high voltage generator using semiconductor opening switches for atmospheric discharge

Abstract

Summary form only given. Nanosecond repetitive pulsed high voltage generator is successfully developed for atmospheric pressure pulsed discharge applications. This generator employs an inductive energy storage scheme with SOS (semiconductor opening switch) at the output of generator to sharpen and multiply the output voltage at high repetition rate. The SOS is specially designed semiconductor diode for using as an opening switch. It has a semiconductor p <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> -p-nn <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> structure and is fabricated to obtain a super hard reverse recovery at large reverse current of what is called SOSeffect. The SOS-60-4, which is an assembly of 80 SOS diodes connected in series to obtain withstand reverse voltage of 60 kV, is used in the present systems. It is able to conduct and interrupt high reverse current (up to 4 kA) in very short time (less than 15 ns). To provide forward and reverse current to the SOS at the high repetition rate, MCP (magnetic pulse compression) circuit and IGBT (insulated gate bipolar transistor) is also employed in the present system. The forward and reverse current pulse width is set to be 400 ns and 100 ns, respectively. As a load, a copper plate-edge discharging gap is used. This discharging gap has a length of 30 cm. The gap distance is 1 cm. The tests was carried out and peak forward current of 90 A, peak reverse current of 380 A were obtained respectively. In these results, peak output voltage of 95 kV, voltage rise time of 30 ns and pulse width of 50 ns were respectively obtained at the discharging gap load at 100 Hz repetitive operation. Streamer like discharges were identified at the load