Electrostatic and magnetic field analyses of 66-kv cross-linked polyethylene submarine power cable equipped with optical fiber sensors

This article presents a 2D finite element analysis for a 66-kV, three-phase, three-core, cross-linked polyethylene power cable with and without three symmetrically arranged optical fiber sensors. The aim of this simulation is to investigate how the electric and magnetic fields and the eddy-current density distributions change when adding these sensors. These electric and thermal (produced by eddy current) stresses govern the cable's lifetime and current rating ampacity, respectively. In the electrostatic analysis, the electric field distributions are studied before and after adding the optical fiber sensors. In the magnetic analysis, three cases are investigated, namely, balanced, unbalanced, and single phasing, where the magnetic field and the eddy-current density distributions are computed at different locations. The use of the optical fiber sensors in such cross-linked polyethylene power cables has no major electrical or magnetic effects. On the other hand, the single-phasing operation represents the worst cable condition due to heat build-up; especially for the cross-linked polyethylene insulation, where the square of the eddy-current density in the individual sheath of the energized phases is roughly three times that for the balanced case.