Corona characteristics of aerial conductors under switching impulse voltages

Corona can be a major factor influencing the attenuation and deformation of switching surge transients. Experimental measurements of corona characteristics are needed for realistic simulations. This paper presents an experimental study of the corona characteristics of solid and stranded conductors under switching impulse voltages. The results include the corona inception voltage, the apparent change in the capacitance of the line conductor, a comparison of charge-voltage (Q-V) curves for positive and negative corona, and the effect of surface roughness. A theoretical corona model represented by an enlarged conductor diameter above inception voltage is proposed and compared with the experimental measurements.