The design of sphere-gap test chamber using Finite Element Method

This paper investigates the effect of an enclosed chamber on the electric field distribution of standard sphere-gap by using Finite Element Method (FEM). The chamber will be used to control the atmospheric condition around the 10 cm diameter sphere-gap in a vertical arrangement. The geometry of the simulation model followed the vertical sphere-gap of the standard IEC60052, by taking into account clearance limits of spheres. The mesh size and the boundary size of the simulation model are chosen by considering both simulation accuracy and time. The maximum electric field between the model of sphere-gap with and without the chamber are recorded and compared. The results show that the chamber with metal cover has a strong effect on the maximum electric field, E_max, of the sphere-gap, while the chamber with insulation cover has an acceptable deviation of E_max.