Independent Pitch Control of Large-scale Offshore Wind Turbines Based on Whale Optimization Algorithm

Offshore floating wind turbines face the challenges of coupled loads such as wind, waves, and currents in complex marine environments, and their power stability and structural load optimization have become key issues restricting system reliability. Firstly, aiming at the uncertainty of manual parameter tuning in the Proportional-Integral-Derivative (PID) for the individual blade pitch regulation of floating wind turbines, a distinct blade pitch control scheme based on the Whale Optimization Algorithm (WOA) to optimize PID parameters is proposed. Meanwhile, in view of the problem that traditional optimization methods rely on test functions and simplified wind turbine models for optimization, which leads to the lack of applicability of optimized parameters under complex working conditions, a multi-objective fitness function is designed that conforms to the requirements of maintaining platform stability and load optimization in wind turbine independent pitch control. The results of FAST-Matlab/Simulink co-simulation show that compared with traditional PID control, WOA-PID control can effectively reduce the tower base load and blade root load, while mitigating the longitudinal motion of the floating wind turbine. It reduces the standard deviation of the wind turbine output power by $33.4 \%$ and the average value of the blade root load by $32.5 \%$, significantly improving the operational performance of the floating wind turbine under complex sea conditions.