Title :
Reignitions in short vacuum gaps after interruption of high-frequency currents caused by ion bombardment
Author_Institution :
Inst. of High Voltage Eng., Aachen Univ. of Technol., Germany
fDate :
2/1/2001 12:00:00 AM
Abstract :
The internal energy increase of the cathode material during the post arc period as a result of the high electrical field at the cathode surface and the highly energetic ions existing in the vacuum gap is studied in this paper by solving the conservation equations of mass, momentum, and energy together, with the equation of state of electrode material in the cathode region. Solving the heat conduction equation in the cathode region, the temperature distribution of the cathode material is determined. The results for copper indicate that a breakdown can occur at the cathode surface some 100 ns after current zero depending on the form of the cathode surface inhomogeneities, the steepness of the transient recovery voltage, and the initial plasma distribution in the vacuum gap. These results are in accordance with experimental measurements
Keywords :
ion beam effects; ion-surface impact; plasma temperature; temperature distribution; vacuum breakdown; vacuum circuit breakers; cathode material; cathode region; cathode surface; conservation equations; electrode material; energy conservation; equation of state; heat conduction equation; high frequency current interruption; high-frequency currents; highly energetic ions; inhomogeneities; initial plasma distribution; internal energy; ion bombardment; mass conservation; momentum conservation; reignitions; short vacuum gaps; temperature distribution; transient recovery voltage; vacuum circuit breakers; vacuum gap; Breakdown voltage; Cathodes; Conducting materials; Electrodes; Elementary particle vacuum; Equations; Plasma measurements; Temperature distribution; Vacuum arcs; Vacuum breakdown;
Journal_Title :
Plasma Science, IEEE Transactions on
