Floating Offshore Wind Turbine Optimized Control for Power Regulation With Experimental Validation

This article proposes a new strategy for blade pitch control to regulate power production while alleviating the negative effects of the structural motions of floating offshore wind turbines (FOWTs). FOWTs frequently experience significant fluctuations in rotor speed when wind speed is above its rated value in the presence of significant wave heights. This condition reduces the power quality while amplifying the fatigue loads, which can result in damage to the generator. To address this problem, designers frequently use simplified models to design controllers, such as the gain-scheduled proportional-integral (GSPI). These models can demonstrate the nonlinear coupling of the platform motions and the rotor speed. However, their performance is limited due to the chosen linearization points. This paper proposes an optimal design method based on metaheuristic algorithms. These algorithms treat the system as a black box, allowing for control parameters tuning considering all degrees of freedom, such as those provided by OpenFAST. The red-tailed-hawk (RTH) algorithm is used to create an optimized GSPI controller (RTH-GSPI) that maintains power while minimizing platform motion. Consequently, the performance is significantly enhanced. Numerical simulations using co-simulation between Matlab and OpenFAST, along with experimental validation using a FOWT prototype, have verified the suggested technique’s efficiency.