Real-Time Determination of Depth of Burial Profiles for Submarine Power Cables

The safe operation of submarine power cables at high load is of highest relevance for an economic and reliable operation of offshore wind farms and submarine interconnection systems. Burial of power cables at a certain minimum depth is often required for mechanical protection of the cable and to avoid too strong heating of the seafloor surface. The depth of burial (DoB) of those cables may vary over time by movements of sand and the cables themselves. Monitoring such changes so far requires, costly yearly surveys using submarine robots. In this study, we present a method to permanently analyze the DoB of submarine power cable formations by using distributed temperature sensing, electric load data, and thermal models of the submarine cable installation. An analysis of field data shows that our method has the capability to detect comparatively fast variations of DoB and also cable exposure events in real installations.