Calculation of the Ionized Field of ±800 kV High Voltage DC Power Lines with the Presence of Charged Atmospheric Particles

Ionized field strength is one of the significant parameters of ultrahigh-voltage direct current (UHVDC) power lines, which determines the geometric design of the lines and human exposure in the electromagnetic environment. It is complex to calculate the ionized field distribution accurately due to the ions generated in the processes of corona discharges on the HV lines' surfaces. Moreover, the existence of atmospheric fine particles with the diameter order of micrometers (μ m) makes the ionized field calculation problem more difficult because the fine particles surrounding the HV lines will be charged and distributed in the areas between the lines and the ground. In this paper, the impacts of charged atmospheric fine particles on the ±800 kV UHVDC transmission lines' ionized field distribution at ground level are investigated by the upstream boundary element method. The algorithm is verified by both calculations and measurements. The contribution of charged particles to the charge density in air is also considered and obtained in the algorithm. This paper may provide some valuable reference for the design of UHVDC transmission lines.