Novel Subsea Cable Monitoring System Passes EMEC Test
A new system for monitoring subsea cables in the offshore renewables sector has completed tests at the European Marine Energy Centre (EMEC) in Orkney, aimed at demonstrating technical and commercial viability of the technology.
The multifunctional distributed sensor system, which is said to lead to improved and more cost-efficient maintenance and repair of underwater cables, has been developed and tested under a one-year Innovate UK-funded project CLEMATIS (Cable Lifetime Enhancement via Monitoring using Advanced Thermal and electrical Infrastructure Sensing).
The CLEMATIS project included the Fraunhofer Centre for Applied Photonics and Synaptec, whose technologies were integrated into the system, and EMEC and SEA, who provided market intelligence, test equipment and facilities to enable the system to be tested in real life conditions.
The project built on the 2016 desk-based ORCHIDS feasibility study which identified various breakthrough techniques that could be combined into a single power cable monitoring system and provide detailed fault prediction, dynamic thermal rating implementation and fault location.
CLEMATIS progressed this initial study from the desk to laboratory demonstrations and early field tests both on and offshore.
Field demonstrations took place at EME, testing the distributed acoustic and thermal sensing capabilities with onshore sections of marine cable.
According to EMEC, early success in these tests provided the impetus to test the system on an installed offshore power cable, thus expanding the original scope of the CLEMATIS project. In June 2018, the system was demonstrated on a live subsea cable at EMEC’s Fall of Warness tidal energy test site.
The CLEMATIS system is a holistic monitoring system that exploits the optical communications fibre in marine power cables. The system turns entire lengths of power cable into reconfigurable acoustic and temperature sensors. A quasi-distributed electrical system makes use of the same optical fibre to interrogate passive electrical current and voltage sensors distributed throughout the infrastructure.