Armor losses in AC submarine cables: new setup and experimental results

According to the guidelines outlined in the International Electrotechnical Commission's standard document IEC-60287, it is possible to mathematically calculate the losses of power cables. One of the losses that can be evaluated is the armor losses in submarine cables. The armor has a double function, providing both mechanical protection to the cable and acting as a shield against external electromagnetic interference. Nevertheless, the metal armor gives rise to additional losses. As the demand for undersea power transmission increases with the growth of offshore installations, understanding and minimizing armor losses in three-core submarine cables become crucial for optimizing the efficiency and reliability of these critical components. Aim of this thesis is to develop a reliable and effective test procedure and experimental test setup to measure the aforementioned losses. Experimental results showed a good fit with the theoretical results and were performed on 66 kV AC static three-core submarine cable and on a 66 kV AC dynamic submarine three-core cable. The cable under test are inter-array cables that are going to be installed in actual offshore wind parks in north Europe. The cable system is specifically designed and constructed for use with non-anchored wind turbines in deeper waters, using rigorously tested dynamic cables, which have an enhanced ability to withstand mechanical fatigue over the entire expected life of a system. Once developed the effective and reliable test setup, measurements were performed and compared with the results based on the standard IEC-60287 confirming how the formula proposed in the standard, and recently updated in the Technical Brochure TB908 “Losses in Armored Three Core Power Cables” provides an overestimated value for such losses. Overestimating cable losses may necessitate larger core cross-sections, leading to an excessive use of materials, which in turn results in a costlier cable and installation process.