Steady state modelling of three-core wire armoured submarine cables: Power losses and ampacity estimation based on FEM and IEC

This paper introduces Finite Element Method modelling techniques applied to wire armoured submarine three-core cables, whose nominal voltages range from 36 to 245 kV. The analysis is focused on the implementation of the net voltage cancellation principle in a 2D environment. The model is utilised in a comparative study with the IEC 60287 Standard, developed in terms of power losses, loss factors and cable ampacity. Despite the model limitations, the estimated loss factors are mainly in compliance with the state of the art, verifying the widely recognized conservatism of the IEC standard. Simulation results confirm that the wire armour stranding is not accounted for, but also suggest that the ampacity underrating might be due to other inaccuracies in the IEC modelling indications. Overall, the difference in terms of current rating between the FEM and the IEC approach is found to be voltage dependent and more relevant for high voltage designs.