When evaluating the electromagnetic environment of high voltage direct current (HVDC) powers lines

a fundamental factor to consider is the ionized field at ground level. China's rapid industrialization and urbanization has led to haze pollution episodes. Ions generated by the corona discharge on the surface of HVDC power lines can adhere to haze particles

giving rise to variations in space charge density

which then impact the ionized field. In this paper

the charging and motion characteristics of the dielectric particle are investigated. The saturation charge amount of the particle and its contribution to the charge density are calculated in the spherical coordinates using the governing equations of the electric field. The terminal setting velocity is calculated based on the Stokes flow of particles in the gravitational and electrical fields. The mobility of the charged particle is also analyzed. This paper will serve as a valuable reference for the modeling and calculation of the ionized field of HVDC transmission lines

with the presence of dielectric particles.