High-repetition-rate pseudospark switches for pulsed high-power lasers

摘要

Abstract: The experimental results of high-repetition-rate pseudospark switch testing are reported, with particular interest in applications like high-repetition- rate, high-average power excimer lasers and pulsed TEA CO$-2$/ lasers. Typical test parameters are hold-off voltage of about 20 kV, peak currents around 15 kA, and pulse durations of less than 100 ns, discharge conditions that are typical for high average power excimer lasers. These were realized in a low inductive discharge circuit using discrete ceramic capacitors of up to 10 nF total capacitance and an impedance of about 1 approximately ega@. The resulting peak currents were about 19 kA in the short-circuited, ringing discharge. A special feature of the switch is being capable to withstand severe current reversal, high rates of current rise of about 5$+*$/10$+11$/ A/s and peak currents above 20 kA. Some 10$+7$/ shots have been performed with a sealed-off metal-ceramic pseudospark switch with integrated hydrogen reservoir without degradation of the switch performance. In this setup, repetition rates of up to 1.8 kHz were achieved. The switch-triggering behavior and measurements of the switch resistance in dependence of the peak current are reported.!