Ampacity Estimation for Submarine Power Cables Installed in Saturated Seabed—Experimental Studies

Abstract

The maximum current carrying capacity (ampacity) of power cables depends on the heat transferability of its surrounding medium. Submarine power cable ampacity is calculated conventionally following the international standards defined for underground cables. In reality, the thermal behavior of submarine environments differs significantly from its underground counterpart as the porous sediments are constantly water saturated. In this article, finite element method (FEM) results were used to determine the factors affecting the ampacity in the submarine environment. A method to calculate the ampacity using external thermal resistance considering two series resistances—conductive resistance (of the solid phase sediment) and convective resistance (due to the natural convection in the pore fluid, water) is proposed. An experimental setup was developed to validate the FEM simulations and the numerical method. The results indicated that the inclusion of convective heat transfer in the proposed method obtained a more precise ampacity estimate compared to that of the standard methods.