Calculation of Ion Flow Field Around Metal Building in the Vicinity of Bipolar HVDC Transmission Lines by Method of Characteristics

In this paper, a 3-dimensional method of characteristics is used to calculate the ion flow field around a metal building in the vicinity of bipolar HVDC transmission lines. The surface charges are introduced to make sure that the surface of the metal building is equipotential. An improved iterative method is proposed to solve the ion flow field. A reduced-scale test under laboratory conditions is carried out to verify the calculation results. Comparison of the results with those by Deutsch Assumption shows that although the two groups of results on the ground are in good agreement, the electric fields in space are different because the method of characteristics considers the effect of space charges on the direction of the electric field. The ion flow field around a metal building in the vicinity of a 800 kV transmission line was calculated with the method and discussed.