Calculation and measurement of electric field under HVDC transmission lines

Laboratoire de Génie Électrique, Université A. Mira de Béjaïa, 06000 Béjaïa, Algeria

Corresponding author: dkasdi@yahoo.fr

Received: 11 March 2006
Revised: 29 October 2006
Accepted: 11 December 2006
Published online: 24 January 2007

Abstract

A stable corona discharge in a two conductors-to-plane configuration is analysed in this paper. A linear biased probe, without end-effect, has been adapted to a linear geometry and is used for the first time to measure the ground-plane current density and electric field during the bipolar corona. The values of the electric field and the current density are maximum under the two coronating conductors and decrease when moving away from them. Furthermore, a hybrid technique is developed to obtain a general solution of the governing equations of the coupled space-charge and electric field problem. The technique is to use the finite-element method (FEM) to solve Poisson's equation, and the method of characteristic (MOC) to find the charge density from a current-continuity relation. The model avoids resorting to the Deutsch assumption. The computed values are in good agreement with experimental data.