Computation of three-phase corona power loss in fair weather

A method is developed for calculating the power loss due to corona on three-phase transmission lines in fair weather. In this method, emission of ions takes place from the coronating phase conductors into the surrounding space when the conductor surface field exceeds the corona onset value. The space charges are simulated by discrete line charges, and the charge simulation technique is used to calculate the charge emission from the phase conductors during corona periods over both the positive and negative half-cycles. The displacement of the space charges is governed by the prevailing field, which sums the contributions of all discrete line charges in space and those simulating the phase conductor. The calculated corona power loss values agreed well with those measured experimentally.