Hybrid Method of FEM and Divergence Theorem to Analyze Ion Flow Field Including Dielectric Film’s Accumulation Charges

Due to the dielectric film with charges from corona discharge of high-voltage direct current (HVDC) overhead lines, the electric field near the greenhouses covered by the dielectric film can be distorted. The electric field at some position on the ground level can be measured under the dielectric film. However, the distribution characteristics of the electric field cannot be obtained. In this article, based on the measurement results of some defined points, an algorithm to calculate the ion flow field with the presence of a dielectric film is proposed. Poisson’s equation and the current continuity equation are iteratively solved by the finite-element method (FEM) and the divergence theorem, respectively. The experiment validates the validity of the hybrid method. The research is helpful to understand the influence of charged dielectric film fully.