Monitoring of Subsea Tidal Energy Transmission Cable in the Minas Passage

Abstract

This study presents an analysis of measurements made from an orientation sensor placed in the subsea end of two tidal power subsea transmission cables deployed in the Minas Passage at the Fundy Ocean Research Centre for Energy tidal power test site. Monitoring the ends of the cables is important to ensure the stability of the ends seabed in the strong tidal environment. Movement of the cable ends could result in cable damage or reduced lifespan of the cables causing setbacks for operations at the tidal energy the test site. The sensor package was tested prior to deployment with the subsea transmission cables to determine the accuracy and expected variation of the orientation and accelerometer measurements. With this understanding of the expected variation of the sensor under static conditions, thresholds were selected to identify movement and changes of orientation of the cable abandonment terminations. Data collected from the sensor packages in the deployed cables indicates that the abandonment terminations of the two cables were stable on the seabed over the data collection period. Accelerometer measurements collected from one of the two cables indicated an impact to the abandonment termination but did not correspond to a change in orientation measurements.