Influence of Current Limiting Resistor on the Breakdown Development Process of Vacuum Gaps

Current limiting resistors are wildly used to reduce the damage of a breakdown on insulation performance of vacuum gaps during conditioning and operation of vacuum devices. It has been found that a high current limiting resistor could influence the development of process of a vacuum breakdown, but the mechanism and characteristics remains unclear. The objective of this paper is to experimentally investigate the influence of current limiting resistor on the breakdown development process of vacuum gaps. The influence of different resistance values was investigated with still image and non-contact measurement of the gap voltage. Results showed that the different breakdown modes could occur under different resistance values. When the resistance is less than <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{10} \mathbf{k}\mathbf{\Omega}$</tex>, an arc column connecting anode and cathode could be observed in the still image, with the gap voltage remained low. When the resistance is larger than <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{30}\ \mathbf{k}\mathbf{\Omega}$</tex>, the light could be observed only near one of the electrodes, with the gap voltage recovered almost immediately after collapse. When the resistance was <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{20}\ \mathbf{k}\mathbf{\Omega}$</tex>, the breakdown development mode could transit between the above two modes. A simplified simulation model of the breakdown development process was proposed to explain the phenomenon.