Analysis on simplified model and error of three-dimensional calculation for 3D electric field in substation

Abstract

As the substation is the place with the most concentrated primary and secondary equipment in the power system, the electromagnetic environment has been of more interest. Therefore the calculation and assessment on the power frequency electromagnetic field in high voltage substation become increasingly important. In this paper, the 3 D models of the substation element were built. The equipment such as conductor, insulator and grading ring which were regarded as research objects was simplified in geometry to reduce the difficulty of subdivision and the number of subdivision, and also to increase the computing speed. In the paper, finite element method was used to calculate electric field intensity at 1.5 m horizontal plane. And an example of a 500 kV substation interlayer was used to compare the electric field intensity of the simplified model with that of the original model. The results show that the relative error is between -7%-11% within 8 m from the edge of the model and -3%-5% beyond 8 m. The error is less than 5 V/m beyond 15 m from the edge of the model. The computation complexity of the simplified model is a quarter of the original model, so the effect of the simplification is satisfactory.