Avoiding Current Loss in an X-Pinch by Shortening the Gap between Anode and Cathode

摘要

A current loss happens in the load section of an X-pinch, and it most possibly results from a vacuum breakdown somewhere from the side top of the cathode outward to the anode. The current loss was avoided by shortening the a-c gap, which is the gap between the anode and the cathode. It was found that the shortening of the a-c gap has reduced the impedance of the a-c gap, leading to a reduced impedance of the load section. The smaller impedance has two effects. If the incident voltage wave to the load section is kept unchanged, the voltage applied to the load section is lowered due to the lesser reflection as a result of the smaller impedance of the load section. If the voltage applied to the load section is kept unchanged, the voltage applied to the a-c gap is reduced due to a decreasing percentage of the a-c gap impedance in the load impedance. Both effects work together to reduce, in turn, the voltage applied to a-c gap and the electric field in the region close to the side top of the cathode, which avoids the breakdown as well as the current loss.