新型海上风电支撑结构设计与分析

THE DESIGN AND ANALYSIS OF THE NEW TYPE SUPPORT STRUCTURE OF OFFSHORE WIND TURBINE

为解决海上风电基础结构存在的材料强度利用率低、应力集中等问题,提出一种新型桁架式海上风电支撑结构。建立设计水深为10m的三维有限元模型,利用ANSYS有限元分析软件首先进行结构模态分析,得出固有频率值,以确定结构不会与风机的工作频率耦合发生共振。对包括风机运转载荷在内的6种不同工况进行静力和动力分析,得到静力分析结果和单元的时程曲线,与传统的单柱式进行比较,结果表明:新型海上风电支撑结构动力分析结果与静力相比,顶部最大位移增大0.002m,最大von Mises应力增大2.3MPa,低于相同刚度单柱式结构的0.026m、25.7MPa,具有良好的动力性能。

To overcome the shortcomings of the base structures of the offshore wind turbines nowadays such as the low in utilization ratio of material strength and stress concentration, a new truss type of support structure of the off- shore wind turbine was put forward. And the three-dimensional finite element model with a design water depth 10 meters was built. Firstly the modals were analyzed in the finite element model to ensure the support structure can＇ t couple with the operating frequency of the wind turbine avoiding the resonance. Then, the special finite element software ANSYS was used to obtain reliable results of static analysis and dynamic analysis under six kinds of load cases including the operation loads of wind turbine. The results of static analysis and time-history curves showed that the new type of support structure of the offshore wind turbines have sufficient strength requirement and also show a better dynamic behavior. The maximum displacement at the top of the structure increase 0. 002m, and the maximum von Mises stress increase 2.3MPa, lower than the results of monopole 0. 026m and 25.7MPa.