Research on the Loss Characteristics of 35 kV Submarine Cable Based on Multi-field Coupling

35 kV underwater cables are commonly used for the transmission of electrical energy in nearshore offshore wind farms. Investigating the loss characteristics of these cables improves in enhancing the efficiency of energy transmission. This paper presents the construction of a multi-physics coupled electromagnetic-thermal-fluid underwater cable simulation model using COMSOL software. The model aims to calculate the electromagnetic losses in each layer of the underwater cable accurately. This study examines the influences of various laying methods, seawater temperature, seawater velocity and burial depth on loss characteristics of submarine cables. The simulation results show that the electromagnetic loss of the submarine cable is spirally distributed along the cable axis. The total losses of the submarine cable increase with the increase of seawater temperature and seawater velocity. Furthermore, the losses in the shielding layer and armor layer demonstrate a decline as cable resistance surges with temperature.