Efficient New Approach for Boundary Conditions on a Bipolar Corona System

A new approach for the simulation of corona discharge on high voltage direct current transmission lines is presented in this paper with special focus on the boundary conditions. With the help of the new approach, the ion current density (sometimes also called corona current density in literature) resulting from the corona discharge, the electric field strength and the space-charged potential field can be calculated numerically. Compared to the conventional approach for the boundary conditions of space charge density at the conductor surface, the new approach leads to considerable performance advantages with respect to the convergence. In addition to presenting the basic theoretical modelling and simulation of the corona discharge, the method for the boundary conditions is then explained in more detail. The evaluation and analysis of the results show that this approach can be used for calculating the important quantities which occur on a bipolar transmission line.