Critical parameters of gas cavities in dielectric liquids stressed with high electric fields

Abstract

Electric field stimulates formation of gas-filled cavities on sharp electrodes in insulating liquids which may initiate the dielectric breakdown of these liquids. Using an analytical model based on electrical and thermodynamic properties of fluids, the critical dimensions of gas-filled bubbles in ester fluid and transformer oils stressed with an impulse electric field were calculated. The results obtained in this paper could be important for the optimisation of the application of these liquids in high voltage and pulsed power systems.