Prediction of dielectric strength in SF6 voltage transformer by finite element analysis

A voltage transformer is a measuring apparatus which is used to change by secondary voltage to primary voltage in the high tension line. This paper deals with the finite element analysis for the dielectric strength prediction in a voltage transformer which is both two-dimensional and three-dimensional shape. The region of corona and high voltage shield that is difficult to two-dimensional analysis is solved by using three-dimensional analysis. According to shift location of corona shield, the electric field intensity obtained from finite element analysis is compared with dielectric strength. The accuracy of electric field analysis is enhanced by three-dimensional analysis.