| Increased prospects of transmitting electric power by high voltage AC have created a growing interest in the study of the problems associated with corona on AC transmission lines. These problems are power loss, audible noise and radio interference. In rainfall weather, these problems increase to such an extent that they represent serious limitation to the use of extra high voltage. Using coated conductors is a solution proposed to reduce these problems. In this thesis, a theoretical study using computer simulation is presented to calculate, for the first time, both the positive and the negative corona onset voltages for coated conductor.;In addition, the effect of different parameters such as the conductor radius, height and the coating layer permittivity on the ionization zone thickness, the growth of primary avalanche and the onset voltage is presented. A comparison between the onset voltage for coated and bare conductors of the same outer radius is made to appreciate the effect of coating on improving the corona performance of high voltage conductors. |
