Concerning the separation of space charge at the DC cable joints interfaces

This paper presents a study concerning the experimental and theoretical determination of the charge separated at the EPR/XLPE joint interface.Taking into consideration the values of the electrical conductivities and permittivities experimentally determined, the relaxation times of the electric charge, charge density s separated at the interface EPR/XLPE and those of the electric field were computed, both in electrostatic and steady-state regimes.It has been found that the computed values of s are close to those determined experimentally, that s increases in time and with temperature. The higher values of s lead to the intensification of the electric field during the operation and of the residual electric field after power-off.