Model-free semi-active structural control of floating wind turbines

This paper addresses the load/vibration reduction problem of offshore floating wind turbines (FWTs). Based on the tuned mass damper (TMD), a novel semi-active control method is designed to mitigate the floating platform’s structural vibration. Different from existing results, the proposed control method is model-free and insensitive to system uncertainties and unmodelled dynamics. We base our design on the model-free adaptive control (MFAC) method. A data-based surrogate model is developed to approximate the unknown FWT dynamical system through the dynamic linearization technique. In addition, a quadratic programming (QP) module is embedded in our MFAC-based semi-active structural controller for constraint handling and control allocation purposes. High-fidelity simulations of FWTs show that our model-free semi-active structural controller can address the limitations of existing results and significantly reduce the platform’s vibration.