Electric Field Distribution in High Voltage XLPE Cable Affected by Various Cavities

Since it is very hard to maintain the underground cables once installed, much care should be taken to ensure the safety, long life and high quality of its components. In light of this, electric field distribution study in a 245 kV AC Cross-Linked Polyethylene cable recently made by the Algerian factory (CABEL) is carried out. Finite element method is used to study the electrical stresses, which are the main factor that affect the cable service life. The cable electric field distribution is investigated, focusing on the influence of the presence of cavities and defects. To make a deep analysis, all the cavity parameters are taken into consideration, this allows to make a comparison of the field distortion and to highlight the critical cases which can affect the cable performances. The investigation results reveal that the electric field enhancement depends on the nature, the position and the shape of the corresponding cavity. Moreover, the presence of very sharp water cavities in the interface conductor-inner semiconducting layer is the most harmful case.