Innovative Depth of Burial State (DoBS) method for offshore power cable monitoring
With the actual accelerated transition towards more sustainable energies, the deployment of wind farms and submarine power cables has significantly increased in the last few years and will expand significantly in the near future. Therefore, monitoring the growing number of offshore power cables has become very important to identify possible damage risks and avoid long power outages at an early stage. In fact, these cables are commonly buried during the installation phase but may suffer from exposure due to waves and seabed currents. The exposed offshore cable sections may then represent a threat due to possible damage by fishing and anchoring activities which generates costly repairs and power outages, in addition to unforeseen influences on the sensitive marine environment.
AP Sensing has implemented a fast and accurate approach to calculate the depth of burial state of submarine power cables based on Distributed Temperature Sensing (DTS). The effectiveness of this method is demonstrated by comparing the calculated Depth of Burial State (DoBS) results with the exposed locations determined during a Remotely Operated Vehicle (ROV) survey on the 500 kV Skagerrak4 HVDC interconnector between Norway and Denmark.
Based on our DoBS solution, we were able to correctly determine all exposed cable positions, in addition to locations with shallow exposures and ducted cable sections in a surveyed offshore length of approximately 22 km.