Demonstration of a basis for tall wind turbine design

Current load cases, as specified by the IEC standard used to design wind turbine components, were developed using short term wind inflow measurements on wind farms at hub heights of 60m and below. Since such load cases can be insufficient for large wind turbines above 100m hub height, this project aims at demonstrating the impact of wind inflow in the range between 100m and 200m altitude on wind turbine loads through measurement of atmospheric characteristics and loads on a full-scale turbine performed at Høvsøre in Denmark. The project will also demonstrate the impact of the new load cases that are developed on the certification envelope of existing turbines, which is crucial for the wind turbine industry. The proposed work comprises five work packages which address the following: - Installation and measurement of wind data at altitudes beyond 100m; - Wind data analyses and modeling of new load cases; - Demonstration of loads on a large Siemens wind turbine at test site and demonstration of the impact of the new load cases on the certification envelope of existing Suzlon turbines; - Recommendation to the IEC 61400-1 standard; New load cases and detailed methodology for determination of extreme and fatigue loads; - Assessment of safety factors for IEC 61400-1 load cases.