The influence of Airflow on Corona Discharge on Overhead Ground Wire of UHVDC Transmission Line During Lightning

Corona discharge phenomenon around the overhead ground wires produces large amount of ions that can prevent the onset of upward leader on overhead ground wire during thunderstorms. In the present study, simulations on corona discharge on overhead ground wires have been conducted in detail with a two-dimensional geometrical model. During simulation, only positive ions and negative ions are considered with ionization process, recombination process, diffusion and migration movement. A composite electric field has also been applied by thundercloud, downward leader charge and operation voltage of UHVDC transmission lines. Besides, the influence of airflow on corona has also been studied in detail. Simulation results indicate that there’s significant difference of corona discharge between the left and right overhead ground wire and the influence of airflow on corona discharge tend to be less significant as downward lightning leader propagates to some certain extent.