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...

This study combines multi-year mesoscale modeling results, validated using offshore buoys with highresolution bathymetry to create a wind energy resource assessment for offshore California (CA). The siting of an offshore wind farm is limited by water depth, with shallow water being generally preferable economically. Acceptable depths for offshore wind farms are divided into three categories: 20...

Wind turbines are increasingly becoming significant components of power systems. To evaluate competing wind energy conversion technologies, a real-time Wind Turbine Emulator, which emulates the dynamic torque produced by an actual turbine has been developed. This is necessary since the real world performance of a wind turbine, subjected to variable wind conditions is more difficult to evaluate ...

Offshore wind turbine blades suffer from various faults such as blade angle asymmetry, icing, and bends. Replacement of rotor blades normally involves heavy transportation (e.g., vessel and crane), and dependency on weather conditions. As a result, wind turbines come to a long standstill and costs on energy production increase. One approach to reducing the downtime and costs is to apply a prope...

For the first time, global ocean usable wind power is evaluated for modern offshore turbine characteristics including hub height, usable portion of the wind speed distribution and siting depth. Mean wind power increases by 30%, 69% and 73% within the tropics and northern and southern hemisphere extratropics, respectively, between hub heights of 10 m and 100 m. A turbine with a cut-out speed of ...

The stratification of the atmospheric boundary layer (ABL) is classified in terms of the M-O length and subsequently used to determine the relationship between ABL stability and the fatigue loads of a wind turbine located inside an offshore wind farm. Recorded equivalent fatigue loads, representing blade-bending and tower bottom bending, are combined with the operational statistics from the ins...

[1] For the first time, global ocean usable wind power is evaluated for modern offshore turbine characteristics including hub height, usable portion of the wind speed distribution, and siting depth. Mean wind power increases by 30%, 69%, and 73% within the tropics and Northern and Southern Hemisphere extratropics, respectively, between hub heights of 10 m and 100 m. A turbine with a cut‐out spe...

In the design of land-based or offshore wind turbines for ultimate limit states, long-term loads associated with return periods on the order of the service life (20 years, usually) must be estimated. This requires statistical extrapolation from turbine load data that may be obtained by simulation or by field tests. The present study illustrates such extrapolation that uses field data from the B...

With appropriate vibration modeling and analysis the incipient failure of key components such as the tower, drive train and rotor of a large wind turbine can be detected. In this paper, the Nonlinear State Estimation Technique (NSET) has been applied to model turbine tower vibration to good effect, providing an understanding of the tower vibration dynamic characteristics and the main factors in...