TRANSVERSE-FLOW 50-KV TRIGATRON SWITCH FOR 100-PPS BURST-MODE OPERATION

An inexpensive, compact, three-electrode (trigatron) switch utilizing transverse gas flow was developed for burst-mode applications. The swi tch is cooled by adiabatic expansion from three built-in miniature noz zles and the interacting flow streams serve to sweep hot discharge gas es from the electrode region. Tests demonstrated control of an average power of 100 kW for 10 s bursts at repetition rates up to 100 pulses per second (pps) while maintaining a hold-off voltage up to 50 kV. Und er these conditions, the switch commuted currents up to 6 kA with a pu lsewidth of 10 mu s. The cost of operation is reduced by using oil-fre e and dry air at a supply pressure of 500-1000 kPa and a mass flow rat e of 0.5-8 g/s. Minimum switch jitter is obtained using a rounded-tip trigger pin flush with the adjacent electrode and an optimum trigger v oltage that causes breakdown first between the trigger pin and opposit e electrode. (C) 1996 American Institute of Physics.