Development of a digital twin of an onshore wind turbine using monitoring data

The present paper has two main objectives: (1) to create a digital twin of an onshore wind turbine to provide to the owner of the wind farm a tool for continuous tracking of accumulated fatigue damage and evaluation of alternative operation strategies; (2) to perform the first tasks for the creation a reliable numerical of a floating wind turbine to simulate experimental data for the testing of monitoring tools on this type of wind turbines. A numerical model of an onshore wind turbine was created with FAST software developed by the US National Renewable Energy Laboratory (NREL). The structural and mechanical properties of the structure were calculated from the geometric properties of the tower and blades. The aerodynamic properties of different sections of the blades were computed with 2D models created with ANSYS Fluent. Having the wind turbine fully characterised, the control mechanisms were calibrated using data from the manufacturer catalogues. Numerous time series of wind excitation for different operation conditions were generated, and the structural response computed. Additionally, the Supervisory Control and Data Acquisition (SCADA) operating in parallel with a series of extensometers and accelerometers located in strategic points along a real wind turbine tower and blades provided a full description of the internal forces in both locations and the estimation of the modal properties for different operating conditions. Both measured and simulated response allowed the identification and validation of structural dynamic properties and static and dynamic internal loads. In spite of several approximations and simplifications, the results obtained with the numerical model were in good agreement with the ones measured in the field.