Influence of SSI effect on the dynamic responses of next-generation large offshore wind tur-bines
In order to further reduce the cost of wind power,employing 15 MW or even higher capacity wind turbine has been the major development trend in the future wind energy market.This paper has developed the soil structure interaction model of the IEA 15 MW monopile wind turbine using a set of linear springs by improving the capability of FAST due to the demand of investigating the SSI effect on the dynamic responses of next-generation large offshore wind turbines.The nacelle vibration and bending moment of the support structure under normal power production and extreme conditions are obtained.The results indicate that the ignorance of SSI effect significantly underestimates the tow-er-top and mudline bending moments under power production load cases.The SSI effect has an insignificant influence on the dynamic responses of the wind turbine under the extreme conditions.Specifically,the fatigue damage of the support structure at the mudline is only predicted with an error lower than 3%under the 50-year return period extreme condition.Nonetheless,the SSI effect has a dominant influence for the low wind speed conditions.The tower top and mudline bending moments are underestimated by 37.6%and 20.1%,respectively,if the SSI effect is ignored.The axial mode of the foundation is activated,resulting in an intense nacelle vibration and a huge increase to the fatigue damage of the support structure.The study has verified that the SSI effect is mandatorily considered in the design of large offshore wind turbine structures.
万方数据
维普
