Efficient, compact power supply for repetitively pulsed, "triggerless" cathodic arcs

A power supply for "triggerless," repetitively pulsed cathodic arcs has bee n developed. It is based on a thyristor-switched, high-voltage, high-curren t, pulse-forming network (PFN). It can provide high pulsed currents (up to 2 kA), with duration of 600 mu s, and pulse repetition rate of up to 10 Hz. Higher repetition rates are possible at lower current. The rectangular pul se shape and amplitude are reproducible to within a few percent. Cathodic a rc initiation is extremely reliable because the charging voltage is much hi gher than the minimum starting voltage for the triggerless arc initiation m ethod. The energy utilization efficiency is very high by intentionally mism atching load and PFN impedances and by using an efficiency-enhancing diode; the stored energy is dissipated primarily in the arc. [S0034-6748(99)02012 -2].