Electrode phenomena and lifetime considerations in a radial multichannel pseudospark switch

Abstract

A radial multichannel pseudospark switch for pulsed power applications with pulsed currents of more than 100 kA, hold-off voltages up to 30 kV, and pulse durations [full-width at half maximum (FWHM)] of several microseconds is presented. Investigations of the electrode phenomena show that the discharge current is nearly homogeneously distributed over a large electrode area of at least 10 cm/sup 2/. This is a prerequisite for low electrode erosion long lifetime operation has been proven in tests in a device for producing shock waves for material processing and in a pinch plasma X-ray source. In the shock wave generator, peak currents up to 60 kA occur and in the plasma focus device peak currents up to 130 kA have been used. In both cases, after 60000 shots with the water spark and even 10/sup 6/ shots in the plasma focus device, the electrodes show negligible erosion.