Balance between test result and analysis for medium voltage system

Abstract

This paper describes the comparative study and establishes the relationship between experimental test results and finite element method (FEM) analysis results for the medium voltage air insulated system. A specific lightning impulse voltage has been chosen for this study as per the preliminary test results. An experimental test setup has been designed and manufactured for the test. And an electrostatic 2D analysis has been done on the experimental setup by using commercially available FEM-flux software. The analysis results are compared with the real laboratory test results. The experimental test and FEM analysis was carried out on the test setup with and without insulating screen between phases and phase to earth to study the improvement in the dielectric behavior. The main goal of this study is to establish a relationship between the analysis and the test results to gain confidence on the analysis method and at the same time to use similar analysis method for dielectric design in a medium voltage system to reduce the time taken for initial product developmental tests certain extent. The study reveals the values of electric field strength to be considered for an air insulated medium voltage product design, which is further validated by real product verification tests. (4 pages)