Research on Cyclic Ampacity Computational Model of High Voltage AC Submarine Cables Under Typical Load Profiles

Currently, the selection of submarine cables is primarily based on steady-state ampacity. However, in practical situations, submarine cables are not always operating at full load, resulting in a difference between the steady-state ampacity and the actual maximum current that the cable can withstand. In this paper, based on the IEC-60853 standard, the periodic load corresponding to the submarine cable’s cyclic ampacity is studied. A computational model is developed to calculate the cyclic ampacity of the submarine cable under typical cyclic load curves. The COMSOL finite element analysis software is used to establish a multi-physics simulation model for high voltage AC submarine cables under different installation methods, including burial and laying. The influence of environmental factors on the cyclic ampacity of the submarine cable under these two typical installation methods is investigated. The results show that under the burial installation method, as the seabed depth increases and the soil depth decreases, the cyclic ampacity of the cable increases. Under the laying installation method, as the seabed depth increases, the cyclic ampacity of the cable also increases. Furthermore, both the steady-state ampacity and the cyclic ampacity of the cable under the laying installation method are higher than those under the burial installation method. The findings of this study can serve as a reference for selecting the installation method and cable type for submarine cables.