Distribution of ion flow field quantities in air under HVDC transmission lines

Abstract

This paper presents computed and measured (in a reduced-scale model) distributions of electric field strength E and current density J at ground level under practical HVDC transmission lines in corona. The iterative method of Ref. 1 is used to solve the corona equations for E and J in the case of unipolar lines. Since under bipolar lines, only two unipolar regions (negative and positive) exist at the ground level, the same method is used for the bipolar case also. Good agreement is observed between the computed and measured profiles of E and J. Mathematical relations for maximum values of E and J as function of various parameters can be utilized in design and analysis of HVDC transmission lines.