To rapidly and accurately calculate the ampacity and conductor temperature of high-voltage submarine cables

a 500 kV extra-high voltage (EHV) AC cross-linked polyethylene (XLPE) submarine cable was used as an object. Firstly

the dynamic evolution of the submarine cable conductor temperature rise under both flat-lay and conduit-through installation scenarios was tested

and a multi-physics finite element simulation model by coupling electromagnetic-thermal-fluid fields of the submarine cable was established. Moreover

the key factors influencing the conductor temperature of EHV submarine cables under direct burial were analyzed by simulation

including the relationship between the effective value of the load current

the seawater temperature

the burial depth

and the conductor steady-state temperature. Finally

a multi-layer feedforward neural network calculation model for the steady-state temperature of the submarine cable conductor was established. The results show that the simulation model

validated by measured data on the temperature rise of the submarine cable conductor

has a calculation error of less than 5%. The conductor temperature increases exponentially with increasing load current and burial depth

and linearly with increasing seawater temperature. The error between the neural network model calculation results and the finite element simulation and measured results is less than 3.5%.