For current offshore wind farms, monopiles are by far the most popular support structure type. However, for deeper water and/or larger turbines, the fatigue loading is becoming critical and the monopile dimensions are exceeding the current economical feasibility. Especially in cases of misaligned wind and waves, the side-to-side fatigue loading at the support structure can become a design driver. Since the industry aims to use standardized rotor-nacelle-assembly (RNA) designs, the goal of this paper is to show the effectiveness of using the RNA as adjustable controller device for site-specific offshore support structure configurations by using active control devices.
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