Calculation of Ion Flow Fields of HVdc Transmission Lines Based on Error Minimization Using Nodal Current Density

An efficient method for analysis of the non-linear interaction between corona-generated space charge and the electric field is developed by minimizing an error function over the entire domain. The error function is defined in terms of current densities at each node by combining element errors that violate the divergence theorem. An iterative process can be effectively conducted without solving large system matrix. The electric field produced by the induced voltage is calculated by the method of moments (MoM), and the computational load is reduced by composing the system matrix exclusively on the conductor surface. To verify the performance of the proposed algorithm, the resulting current density and ground profiles of the electric field are compared to the results from the analytic method and the experiment.