Calculation of Ion-Flow Field of HVdc Transmission Lines in the Presence of Wind Using Finite Element-Finite Difference Combined Method With Domain Decomposition

A combined method adopting the domain decomposition is proposed for analyzing the ion-flow field of high-voltage direct current transmission lines, including the effect of the transverse wind. The upstream finite-element method is used with a dense triangle mesh in the vicinity of bundle conductors to guarantee the accuracy. The upstream finite-difference method is proposed and the larger uniform quadrilateral grid is applied to simulate the ion-flow field in the rest of the region with a satisfactory precision. The calculation process of the Poisson equation is iterated with the Dirichlet-Neumann algorithm to coordinate the solution between adjacent subdomains. The proposed approach improves the efficiency and remains stable with high wind speed. Finally, the influence of wind on the ion-flow field is analyzed and calculations are in good agreement with experimental data and results in the previous literature.