Modal Analysis of 5 MW Wind Turbine Blades

To study the effect of ply orientation and spar structure on dynamic characteristics of large adaptive wind turbine blades, finite element models of 5 MW wind turbine blade were established using Ansys software, to which modal analysis was conducted for blades with different ply orientation and spar structures, and subsequently the first ten natural frequencies and corresponding vibration modes were obtained, while the effects of following factors on the natural frequency analyzed, such as the ply orientation, spar structure and rotating speed, etc. Results indicate that the ply orientation and spar structure of blades have a great effect on the natural frequency; in the twist-bend coupling of blades, the effects of design parameters on the modal shape of blades should be considered so as to avoid vibration failure of blades.