A repetitive nanosecond pulse generator with photoconductive semiconductor and application for atmospheric plasma jets

In this paper, a compact repetitive nanosecond pulse generator is designed for exciting the atmospheric pressure plasma jets (APPJ) in noble gases. To realize the ultrashort pulse output, a novel Si photoconductive semiconductor switch (PCSS) with reflected cavity and two pulsed formed lines were used. Based on the Blumlein topology, the nanosecond pulse generator can produce repetitive pulses with output voltages of up to 15kV, pulse width of ~7ns, and pulse repetition frequencies of 1Hz~1kHz. Using the designed repetitive nanosecond pulse generator, the characteristics of the APPJ are investigated by measuring the voltages and currents and obtaining images of the discharges. Experimental results show that the nanosecnod pulsegenerator has been successfully used to sustain stable APPJs in helium. The length of plasma plume is over 2cm. Furthermore, the effects of flow rate, the applied voltage, and the pulse frequencies on the He APPJs are investigated.