Development of a high-current vacuum arc in a rod electrode system

The development of a high-current pulse electric discharge in a rod electrode system with the current amplitude changing from $10$ to $100$ kA is investigated using a sectional model of a vacuum chamber with the simultaneous recording of the electrical characteristics of the discharge, of the glow of discharge plasma, and of the spots on the electrodes. A phenomenon is revealed of a rapid transition of the discharge from the ignition unit to interrod gaps on reaching an instantaneous value of current from $5$ to $9$ kA. A correlation is established between the moment of appearance of an abrupt drop of voltage across the vacuum arc and the moment of formation of a new discharge channel in the interrod gap. It is demonstrated that various vacuum arc modes in the interrod gap and the multiplication of discharge channels in all interrod gaps are observed with increasing current. The effect of the rate of current increase on the development of the vacuum arc is investigated.