An integral algorithm to evaluate the electric fields associated with HVDC power transmission lines

In this paper, numerical evaluation of ionized field quantities associated with HVDC corona is carried out using charge simulation technique and integral algorithm. And considering the surface charge of each rectangle patches and simulation charge inside the HVDC conductors as unknown variables, a set of quadratic equations are developed on the base of the potential at the boundary, the corona onset field values at the coronating conductor, and continuity of current on each patch. By Using the NGB (Globally convergent inexact Newton method) method the quadratic equations is solved, and the electric field intensity, distribution of space charges and ion current density can be obtained. Different cases of the single conductor above ground are considered, and the computed results show good agreement with available experimental data. Finally, the method is successfully applied to calculating the electric field and the ion current density of a realistic HVDC transmission line.