Impact of fine particles on the direct current electric field of the conductor due to corona discharge

Corona-generated ionized field is an essential electromagnetic parameter of high voltage direct current transmission lines. In order to investigate the impact of atmospheric fine particles on the DC ionized field, distributions of the ground-level ionized field and ion current density were measured under various air contamination extents in a wire-to-ground platform. The fine particles were generated from burning incense. Measurement results show that the magnitude of ground-level ionized field may increase approximately by 20% when particles in the order of 102 μg m−3 exist in air. Restriction effect on the ionized field by using grounded shielding lines was also examined.