Fundamentals of Interruption in Vacuum. Final Report

摘要

Diffuse vacuum arcs were established between copper/bismuth or copper/chromium contacts inside sealed vacuum interrupters. The arc current was rapidly commutated to zero and measurements were made of post-arc current and transient recovery voltage following interruption. The test circuit allowed for control of the steady state current, the rate of change of current before current zero, and the magnitude and rate of rise of the transient recovery voltage. The influence of these parameters on interruption was observed. Two mathematical models were developed to describe events taking place in the arc and in the circuit during the critical period immediately before and immediately after current zero passage. Results predicted from these models are in good agreement with experiment. Theory also explained a brief pause, of the order of 100ns, which occurs between current zero and the instant when the transient recovery voltage begins to rise. (ERA citation 11:023370)