A Static Field Equivalence Method for Simulation of Fitting Surface Electric Field of ± 500 kV DC Yards in Converter Stations

The accurate calculation of the electric field under various working conditions is of great significance to the safe operation of the converter station. In order to improve accuracy of electric field simulation, in this paper, a static field equivalence method was studied for fittings' surface electric field simulation of converter station, the method adopting static field calculation equivalent to transient field calculation under different voltages is presented: the transient electric field can be equivalent to electrostatic electric field under switching of overvoltage; under the typical direct current (DC) voltage waveform of converter station, the transient electric field can be equivalent to the analysis of constant electric field. Two-dimensional (2D) axisymmetric finite element model of post insulator was used as a model to verify the proposed method. The influence on calculation accuracy of constant electric field was discussed. Finally, the method was applied to calculation of the full model of +/- 500 kV DC yards. Computational results showed that the proposed method could improve the calculation efficiency while retaining considerable accuracy.