Integrated control of floating offshore wind farms with reconfigurable layouts

This paper proposes an integrated optimization-based control framework for floating offshore wind farms (FOWFs) with reconfigurable layouts. The framework coordinates four farm-level control strategies, that is, turbine repositioning, wake steering, power derating, and Helix wake mixing, to either (i) maximize total farm power output or (ii) track a prescribed farm-level power setpoint while mitigating wake effects. This integration is motivated by the fact that individual strategies may be effective only under specific conditions or broadly effective but not always optimal, whereas their coordinated use can deliver robust performance improvements across a broad range of operating scenarios. The framework targets FOWFs with reconfigurable layouts, where turbines are mounted on floating platforms anchored to the seabed with sufficiently long and slack mooring lines, allowing them to shift within a certain range and thereby enabling controlled positional adjustments. Given the ambient inflow conditions (wind speed and direction), the framework computes coordinated per-turbine commands, including yaw angles, derating commands that limit each turbine's power to not exceed a prescribed value, and mean-to-peak amplitude of sinusoidal blade-pitch excitation, to meet the farm power requirement and to reduce the wake overlap. Numerical simulations using the Flow Redirection and Induction in Steady State (FLORIS) engineering wake model show that the integrated method consistently outperforms any individual strategy. However, because validation in the FLORIS model remains limited for cases in which yaw-based control, including turbine repositioning and wake steering, is applied simultaneously with Helix wake mixing or power derating on the same turbine, the corresponding quantitative gains should be interpreted with caution. We therefore also considered additional restricted benchmark cases in which these control actions were not assigned together to the same turbine. These cases provide conservative lower-bound benchmarks for the integrated-control studies, while still indicating that the main qualitative benefits of the proposed framework are preserved. These findings highlight the potential of integrated control to enhance the efficiency, flexibility, and adaptability of FOWFs, offering a promising pathway to overcome the limitations and improve the performance of standalone control methods.