Response spectrum analysis of wind turbine with joint action of wind and wave

The single degree of freedom offshore wind turbine system load model is analyzed and calculated by adopting the single degree of freedom linear system response power spectrum method. Some results, including the vibration velocity spectrum, the acceleration spectrum, the shear spectrum of tower bottom, and the moment spectrum, are obtained. Through the analysis of the response spectrum, it is found that the sheer force and the response of moment of the tower bottom are not only dependent on the aerodynamic load spectrum and the wave force spectrum, but are also determined by the natural frequency of the system and the damping ratio. It also does not lay directly on the equivalent mass of the system and the equivalent stiffness. So, it can be deduced that the natural frequency of the system and damping ratios are decisive in the design of the tower frame and foundation.