Modeling and Power Optimization of Floating Offshore Wind Farms with Yaw and Induction-based Turbine Repositioning

Abstract

This paper contributes to the growing research surrounding the topic of wind farm control. Specifically, we investigate the potential of floating offshore wind turbine repositioning with the objective of maximizing the power output of a floating offshore wind farm. This investigation requires the development of a pseudo-dynamic floating offshore wind farm model that combines a modified version of the steady FLORIS wake model with a two-dimensional dynamic wind turbine model. For steady wind conditions and various mooring line lengths, optimization studies are performed using the MATLAB optimization toolbox based on the sequential quadratic programming method. The optimization goal is to determine the set of optimal axial induction factors and nacelle yaw angles of wind turbines that will maximize power production from the entire farm. For a floating offshore wind farm with a gridded $3\times 6$ layout, a maximum relative gain of 53.5% in the wind farm efficiency is achieved. This result corresponds to a mooring line length of 925 m, which yields maximum platform surge and sway displacements of 85.8 and 69.9 m, respectively.