Among various types of floating offshore wind turbines (FOWTs), the tension leg platform (TLP) have relatively small motions due to stiff tendons. Similar TLP applications in industry, tendon failure may lead deteriorated stability and large transient responses, which should be considered as part accidental limit state (ALS) checks at design stage FOWTs. This paper takes WindStar system a repre...

The application of reliability-based design optimization (RBDO) methods to offshore wind turbine systems is highly relevant regarding economic efficiency and for considering prevailing uncertainties within the process. Furthermore, RBDO a very promising approach in optimizing when classification standardization are not fully available. level difficulty already increases including reliability as...

To investigate the aerodynamic characteristics of an Archimedes spiral wind turbine for urban-usage, both experimental and numerical studies were carried out. The Archimedes spiral blade was designed to produce wind power using drag and lift forces on the blade together. Instantaneous velocity fields were measured by two-dimensional PIV method in the near field of the blade. Mean velocity profi...

NOTICE The submitted manuscript has been offered by an employee of the Alliance for Sustainable Energy, LLC (ASE), a contractor of the US Government under Contract No. DE-AC36-08-GO28308. Accordingly, the US Government and ASE retain a nonexclusive royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes. Neither ...

This paper presents a newly developed aero-servo-elastic platform for implementing smart rotor control and shows its effectiveness with aerodynamic loads on large-scale offshore wind turbines. The platform was built by improving the FAST/Aerodyn codes with the integration of an external deformable trailing edge flap controller in the Matlab/Simulink software. Smart rotor control was applied to ...

At Fraunhofer IWES a Modelica Library including all major components needed for load calculations of current offshore wind turbines is developed. The library additionally includes models for external conditions, like wind, soil and waves, and their respective influence on the structures. The library constitutes a large effort in the creation of a highly coupled multiphysics model with Modelica ...

In the next decennia, upscaling even towards 10 MW wind turbines may be necessary to lower the costs of offshore wind energy. This requires considerable reductions of turbine loads. Variable speed turbines with active pitch control are most favorable and prevailing nowadays. Currently, the turbine blades are turned collectively to limit the excess of wind power and to regulate the rotor speed a...

A disturbance accommodating controller (DAC) to reject wind speed perturbations is applied on a 5MW wind turbine mounted on a tension leg platform (TLP). Multi-blade coordinate (MBC) transformation is used to address the periodicity of the floating wind turbine system. A method to apply DAC after applying MBC transformation is developed and several implementation options are presented. Simulati...

Decision support models for offshore wind farm operation and maintenance (O&M) are required to represent the failure behavior of wind turbine components. Detailed degradation modelling is already incorporated in models for specific components and applications. However, component degradation is only one of many effects that must be captured in high-level strategic decision support models that si...