The most significant achievements reached during the project are:
WP1 represents the starting point of WATEREYE project with the definition of the project framework and general system requirements to be developed during the project. For this purpose, a study on corrosion and its effect on the relevant parts of the wind turbine structure has been carried out, allowing the identification the main challenges that corrosion brings to marine structures. External steel surfaces in the atmospheric and splash zones shall be protected by coating systems. Thus, not only structural steel but also protective coatings are defined clarifying the requirements of the WATEREYE solution. Finally, two scenarios (Canary Islands and Scotland East Coast) were selected as test cases. The main purpose of these sites is to be used as example in the validation and testing phase.
WP2 is focused on the design of the physical components of the WATEREYE solution composed by fixed sensor nodes, a mobile node, a drone, a Drone Docking Station and the WATEREYE Computer. The monitoring system was designed and validated in a relevant environment. After the final validation, we can say that the system is capable of remotely estimating the wall thickness losses due to corrosion and the intra-day corrosion rate. This will be useful to reduce the maintenance costs of the atmospheric and splash zones of offshore wind turbines. Corrosion is a relative slow process. It takes a long time (years in general) to induce corrosion on coated steel samples in field tests. Hence, accelerated laboratory testing was needed to produce corroded sampled within the project period. Both non-corroded and corroded, coated and bare steel samples in different thicknesses were produced with the aim of characterizing appropriately the ultrasound sensor nodes to get higher precision. On the other hand, high efforts were done to design a robust drone-based platform able to position accurately the sensor head on the wall.
The main goal of WP3 is to develop algorithms and software tools for ensuring integral intelligent processing of the inspection data generated both by the novel smart sensors developed in WP2 and by the data coming from WTs to optimise the O&M of a single WT. A corrosion prognosis methodology was designed by incorporating a corrosion model and a corrosion indicator extracted from the ultrasound signal. Moreover, a load reduction control algorithm was developed for offshore turbine tower to mitigate the loads. A Weather Research and Forecasting was designed to simulate the weather and turbine operating conditions. The system level data was used by the decision support tool at turbine level, which allowed calculation and scheduling of stochastically economically optimal commissioning actions.
The WATEREYE wind farm management tools developed in WP4 are part of the overall solution with the objective to reduce O&M costs by extending the lifetime of offshore wind turbines. The focus of WATEREYE lies on the protection of turbine towers from failure by preventing both corrosion and material fatigue from progressing. A tool for probabilistic analysis of turbine dynamics in the frequency domain was developed as well as a module of farm-scale turbulence that supports computationally efficient multiscale stochastic simulations in the time domain. Moreover, a control framework was developed that calculates the accumulated damage depending on environmental conditions and the wind farm control. The damage estimate feeds into the method for optimal O&M planning that considers potential power gains in the long and short term, power losses due to derating or shut down, maintenance costs as well as the weather forecast when scheduling maintenance tasks. These tools can be used both for retrofitting existing wind turbines and in novel system developments.
Due to the unavailability to conduct the validation inside a real wind turbine tower, it was decided to build in WP5 a steel structure to simulate a wind turbine tower in a “realistic and feasible way”. Therefore, the final validation took place inside the hangar of PLOCAN’s offshore platform, using this steel tower as the main element to which the system was attached. The WATEREYE monitoring solution was validated both at lab scale in Sint-Truiden (Belgium) and in relevant environment at the PLOCAN’s offshore platform in Gran Canaria (Spain). Therefore, it can be concluded that the validation of the WATEREYE monitoring system has been successfully conducted.
