10m clearance between the wind turbine and vessel allows technicians to walk-to-work through a telescopic gangway

active in offshore wind. The project is half way and will be completed in 2018.

At the beginning of the project, the existing Operations and Maintenance Tool (O&M Tool) developed by the Energy research Centre of the Netherlands (ECN) was shared with the participants. This is a generic tool to determine the operability of maintenance operations at offshore wind parks. During the project weather databases, hydrodynamic databases and operational criteria for human comfort, seasickness and fatigue have been added to the tool. The hydrodynamic databases are generated by MARIN through numerical modelling supported by physical model tests. These databases represent the seakeeping characteristics of five generic maintenance vessels during transit at forward speed and transfer to the turbine in the wind park.

SOV studies So far, the research on maintenance solutions for offshore wind turbines has focused on Crew Transfer Vessels (CTVs), which are up to about 30 m and sail to and from the wind farm on a daily basis, allowing technicians to transfer through ship-to-turbine interaction. Within the OM JIP MARIN has extended this research to include larger Service Operation Vessels (SOVs), which remain on site for a longer period of time and transfer technicians to a turbine by means of a telescopic gangway or alternative access system. MARIN has performed dedicated dynamic approach and positioning (DP) model tests on a generic SOV in sea states ranging from 2.5 m to 3.5

report 21

m significant wave height. These model tests resulted in the stationkeeping accuracy that might be expected from an SOV, and allow the aforementioned hydrodynamic databases to be tuned and verified.

Human factors At the end of 2016 TNO started monitoring technicians during their offshore work maintaining wind turbines. The monitoring campaign is taking place at the Lincs offshore wind farm operated by Centrica. The 270MW wind farm is located on the east coast of England and is operated with CTVs. During the measurement campaign the vessels motions are recorded by BMO, and the technicians fill in questionnaires on their tablet during their working day. By combining the measured vessel motions and the feedback from the technicians on their performance, improved human factors will be developed for this working group.

These will then be added to the O&M Tool allowing the best logistical approach to be selected, taking into account the operational performance of the technicians.

Updated version of O&M Tool In April 2017 an updated version of the O&M Tool, including weather data, hydrody- namics and human factors is provided to the participants. The hydrodynamic databases and human performance will be further developed in the coming year and included in the final version of the O&M Tool.

OM JIP II With 1.5 years still to go for the OM JIP, a follow-up project has already been initiated: the OM JIP II. This project will result in a tool which will optimise the order of maintenance on wind turbines, based on short-term forecasted weather data. Research partners are MARIN, Deltares and the other OM JIP participants.

Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28