Influence of surface pores (defects) on vacuum insulation

Abstract

Up to now field emission was regarded as initiating factor of vacuum insulation violation. Present overview shows that at low values of external field strength (˜106 V/m) gas discharge in pores (defects) of electrode surface starts to play this role. Regularities of this discharge studied by the author explain vacuum insulation characteristics changing understanding of its present destruction mechanism. Experiments were performed at de voltage, hence pre­breakdown currents could be measured. However, the results obtained are valid for other voltage modes, e.g. pulse and high frequency, as well.