An Overview of Analysis and Adaptive Pitch Control of an Offshore Floating Multi-Wind-Turbine Platform

Abstract

This chapter outlines the findings of research focused on the creation of a new semi-submersible Offshore Floating Multi-Wind-Turbine Platform (OFFWIND). The primary concerns addressed involve modeling the aerodynamic forces caused by wind speed on the turbines, as well as the hydrodynamic forces resulting from wind and wave interactions on the entire system. To simulate the rotation of the rotors on the five wind turbines placed on the platform, a multiple-moving reference frame combined with a sliding mesh technique is employed. The evaluation of pressure, velocity, and turbulence intensity contours of the OFFWIND is conducted, particularly concentrating on the downstream turbine which operates in the partial wake of the turbines located upstream. The aerodynamic forces acting on the wind turbines are assessed to analyze their aerodynamic efficiency. The determined aerodynamic loads are integrated with the hydrodynamic forces to assess the platform’s movements in response to wind and wave conditions. An adaptive control algorithm has been developed for blade pitch control. The performance of the adaptive control is evaluated against a standard Proportional-Integral (PI) controller. Simulation results demonstrate that the adaptive controller significantly improves rotor speed stability and reduces power output fluctuations under varying operational conditions.