Transverse-flow 50-kV trigatron switch for 100-pps burst-mode operation

Abstract

An inexpensive, compact, three-electrode (trigatron) switch utilizing transverse gas flow was developed for burst-mode applications. The switch is cooled by adiabatic expansion from three built-in miniature nozzles and the interacting flow streams serve to sweep hot discharge gases 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. Under these conditions, the switch commuted currents up to 6 kA with a pulsewidth of 10 μs. The cost of operation is reduced by using oil-free and dry air at a supply pressure of 500–1000 kPa and a mass flow rate 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 voltage that causes breakdown first between the trigger pin and opposite electrode.