Influence of a metallic wall on 245 kV disconnector behaviour during short-circuit test

Abstract

When testing electrical devices, it is not always possible to provide locals with dimensions large enough to guarantee that metallic elements (walls or other elements) not essential for the test, are located far enough to ensure that they will not affect the distribution of the electric or magnetic field, or forces that may appear during testing of the devices. Some questions to be answered are: a) test results are distorted by presence of these metallic elements? b) if so, to what degree are influenced? and c) how could we quantify its value without building new laboratories, and raising economic cost? The main objective of this paper is to analyse influence of a metallic wall on behaviour of a 245 kV disconnector during short-circuit test developed in laboratory and, compare electrodynamic force on disconnector when the test is carried out with and without metallic wall. Behaviour simulation of disconnector is carried out using finite element method (FEM). Force is calculated using Lorenz force method. Results show that calculated force is strongly dependent on model size and element size.