Discharge characteristics in an asymmetrically-perturbed SF6 gap

Conditions for the generation of true corona in a plane/point/plane SF₆ gap are discussed. For quasi-uniform field conditions, it is shown that corona currents can be sustained only in the low-pressure range. As the gas pressure was increased, these currents were totally quenched. In pressurized gas conditions, UV (ultraviolet)-assisted charge-integrated currents were recorded. It was hypothesized that their observed growth with applied voltage was too weak to bring about a self-sustained current over an extended voltage range beyond corona threshold