Impact of 3D modeling and proximity effect in the computation of submarine HVDC cable impedances

Formulas for both earth return and internal impedances of submarine HVDC cables have been provided in past studies; however, they are based on simplifying hypotheses, e.g. considering 2D geometries, treating armor layers as coaxial tubular conductors, and neglecting the proximity effect between nearby cables. In this paper, a Finite Element analysis investigates the impact of the deviations of realistic geometries and configurations of submarine HVDC cables from idealized ones. In particular, the impact of the twisting of armor wires on internal impedances and the proximity effect in multiple cable configurations on earth return impedance are analyzed.