Method of Increasing the Electric Strength of Vacuum Insulation Using a High-Frequency Vacuum Arc

Resumo

The effect of increasing the electric strength of vacuum insulation of gaps with electrodes from contact CuCr (≅30% Cr) material widely used in vacuum switches subject to conditioning with an AC vacuum arc modulated by high-frequency oscillations is considered. The modulating component stimulates periodic arc interruption and its ignition in new places thereby promoting effective treatment of the entire surface of the electrode pair. In addition, when the high-frequency arc is burning, the voltage drop across the electrodes significantly increases, thereby leading to alternating treatment of both electrode surfaces by intense high-energy flows of charged particles. For such treatment, the special regime of cleaning and local surface melting is used leading to the effective increase of the electric strength of vacuum gaps.