Every submarine power cable contains a fiber-optic assembly. Most windfarms have a distributed temperature sensing (DTS) device for continuous temperature monitoring. Using real-time thermal rating (RTTR) the performance of subsea cables can be increased or a less expensive cable can be installed.
The experiments aimed to establish the relation between the fiber and core (or conductor) temperatures in the cable. Fiber temperature was obtained using a DTS interrogator; thermocouples installed in the conductors yielded the core temperature data. The cable used in this test was a 20 meter-long 1800 mm2, 1000 A export cable.
These experiments validated a new RTTR model proposed by Marlinks: a thermal RC-ladder model based on finite-element (FEM) calculations. Better suited to the complexity of the spacer geometry and existence of the fiber node, the Marlinks-developed model is considered to be more accurate than the industry standard.
