Method of local characteristics for calculating electric field and ion current of HVDC transmission lines with transverse wind

The electric field and ion flow are significantly influenced by the transverse wind around the high-voltage direct current (HVDC) transmission lines. In this study, a new method using local characteristics is proposed to analyse the effect of wind. The present method, called method of local characteristic, updates the ion density based on the local characteristic curve in each second-order finite element method (FEM) element without Deutsch assumption. The defining equation of the characteristics is able to take into account the directional character of the information propagation in convective transport and has a better performance to satisfy the conservation law. The present approach is stable and efficient even in the presence of high-speed transverse wind. Calculations show good agreement with the measurement values of the reduced-scale unipolar model and the full-scale bipolar test line. Finally, the influence of wind on the electric field and ion current is discussed.