Dual Airflow Control Strategy for Floating Offshore Wind Turbine Stabilization Using Oscillating Water Columns

The stability of Floating Offshore Wind Turbine (FOWT) has been the focus of many researchers in the last years. Many concepts proposed the use of passive structural control such as inerter and Tuned Mass Dampers (TMD). This paper presents a new concept combining a barge-based FOWT with Oscillating Water Columns (OWC) to help reduce the undesired vibrations induced from waves and wind. In this work, an airflow control strategy developed for the OWCs integrated in the barge platform of a FOWT. The control strategy has been designed to lessen the pitching of the platform and the displacements of tower fore-aft with the intention of stabilizing the floating platform. This objective is achieved by controlling the air valves located at the top of the OWCs' capture chambers. The comparative study between the FOWT with standard barge and the proposed FOWT with OWC-based barge, based on the analysis of the free decay responses, displays an enhancement in the stability of the platform.