Wind farm array cable risk-based assessment and analysis
Scope of work
Our client, an operator of a large UK wind farm, asked us to conduct an array cable risk assessment as a first step towards developing an RBI (risk-based inspection) plan.
The operator had performed route surveys of the cables and had a good library of data, but needed to understand which cables were most at risk so that integrity management activities could be appropriately targeted.
We performed this study in two parts. The first was an OrcaFlex analysis of two cable bell-mouth spans and a mid-route span on the seabed. Worst-case scour profiles and span lengths were modelled, as well as a more representative, ‘average’, cable span arrangement. The results gave maximum tensions, MBRs and curvatures, and fed into the second part of the study, which was to rank each cable with a risk of spanning, exposure, and third party interaction. The high risk cables within the windfarm were then identified.
We presented our client with indicative physical cable properties from modelled spans, as well as a table of risk-ranked cables. This combination allowed them to not only plan and prioritise their future survey and remedial activities, but also to present the results to the board, highlighting the importance of continued cable integrity management.