The Effect of Electric Field from the Cable Joint to the Breakdown of Insulation in 24 kV Underground Cables

This paper presents the electric field generation of the underground cables (UGs) joint on a cool shrink method by focusing on a breakdown of the cable joint. The study of electric field on the UGs joint was performed by finite element analysis (FEA) with the modelling of cable joint materials and accessories as shown in the detail of this paper. The results showed that the cable connector of (UGs) joint generated the electric filed, which reduced the electric field by defining the connector at an angle α = 45°. Consequently, this can prevent and decrease the case of cable joint insulation breakdown. Since, it can reduce the electric filed remaining about -39.02 % and -38.21 % in the case of II and IV, respectively. Therefore, the cable joint breakdown from electric field can be minimized by eliminating the angle of the cable connector as presented in this analysis. In addition, the related person to the UGs cable joint breakdown must be considered and specify the installer who performed and emphasized the cable joint process seriously. Thus, the cable joint breakdown can be reduced from the human effect and extend the lifetime until their right time without causing the failure of the network system.