The small-size sealed-off triggered vacuum switch TVS-7 designed to switch current pulse to 10 kA at high repetition rate to 1 kHz and maximum voltage to 25 kV is described. TVS switching characteristics are studied systematically versus the trigger current parameters for different polarities of the main electrodes. It is shown the TVS ensures a monotonous current rise of submicrosecond duration with a rate of current rise up to 10¹¹ A/s and a minimum switch-on delay time of 50 ns at a trigger current amplitude of I_t >= 100 A. In the cathode mode of operation the TVS is reliably triggered with reducing of trigger current up to I_t >= 1 A. But in this case current and voltage oscillations occur at an initial discharge development stage. This unstable stage of discharge burning is subjected to investigation. A minimum trigger energy, of about 10 mJ is required to ensure stable conditions of discharge burning with any polarity at the main electrodes. Under the condition power losses at switch-on stage of the TVS are substantially reduced in comparison with those of traditional vacuum switches. This became possible because of the use of a two-stage trigger system of the erosion type and a small main vacuum gap.

Date Published: 1 May 1994
PDF: 4 pages
Proc. SPIE 2259, XVI International Symposium on Discharges and Electrical Insulation in Vacuum, (1 May 1994); doi: 10.1117/12.174651

Published in SPIE Proceedings Vol. 2259:
XVI International Symposium on Discharges and Electrical Insulation in Vacuum
Gennady A. Mesyats, Editor(s)