Coupled Testing of Floating Wind Turbines in Waves and Wind Using Winches and Software-in-the-Loop

Abstract

In 2017 the authors conducted an experimental hydro-aero-dynamic (station-keeping) campaign in MARIN's Offshore Basin aimed at validating its floating offshore wind turbine simulation tools. Since wind turbine dynamics cannot be readily downscaled in presence of Froude-scaled hydrodynamics, a bespoke coupling approach was developed. This was based on real-time load actuation using a winch system jointly with simulation software running on a data feed from the basin acquisition system. The result was a software-in-the-loop experimental setup allowing to introduce controlled aerodynamic loading in the tests based on both the model's live response and simulated turbine physics. The software involved in this campaign, specifically developed for this task, is a customised version of NREL FAST, a standard open-source wind turbine simulator. Software-in-the-loop strategy emerges as a viable option to introduce multi-physical coupling in floating wind turbine tests in a controlled way.