垂直轴风力机塔柱结构的分析及优化

为了避免风力机系统的共振而导致的系统损坏和噪声污染,通过系统动力特性分析和动力学响应计算分析,得到了风力机塔柱的低阶固有频率和谐响应的数据,以及风轮和塔柱之间的动态关系与整个系统的动态特性,为结构动态设计以及优化提供科学依据.首先确定对风力机塔柱系统结构动态性能影响最大的模态频率,提取该阶模态频率作为动态优化的目标,最后分析塔柱结构与风轮之间的动态干扰.结果表明：原设计在风轮以设计额定转速160 r/min运行时,其产生的简谐荷载对风力机塔柱具有十分严重的破坏性,通过增加主轴钢管的壁厚并提高其刚度等优化工作,经计算证明,在激振力不变的情况下,第一阶固有频率得到提高,塔柱的各阶固有频率下的最大位移大幅减小,优化效果明显,达到结构动力设计的目的.

Dynamic analysis and optimization on tower of vertical axis wind turbine structure

In order to avoid the system failure and noise pollution caused by the system resonance in the engineering design,the modal analysis and harmonic response computation analysis have been adopted to obtain the low-order natural frequency and harmonic response data of the tower,as well as the dynamic relation between the wind turbine and tower and the dynamic characteristics of the system.The determination of the modal frequency which plays an important role in affecting the dynamic property of the tower will be carried out for the structure optimizations,and then the dynamic disturbance between the turbine and tower should be analyzed.In result,when the wheel rotates at 160 r/min,the harmonic load has a very serious destructive damage to the tower.In the case of exciting force unchanged of optimizing,first-order natural frequencies is improved,tower column of maximum displacement of natural frequencies of all order significantly reduce.Some optimization works such as increasing the thickness of the tower and enhancing its rigidity have been done which improve the feasibility of the optimization through the dynamic calculation.