中文摘要：

大型风力发电机叶片的结构动力特性是叶片结构设计时考虑的重要方面，其固有自振频率对于整个风力机的安全运行具有重要意义。文章基于现代柔性多体动力学理论和有限元数值分析相结合的方法．对5MW风力发电机叶片的固有振动特性进行分析。结合复合材料叶片结构特性及结构参数，建立了5MW风机复合材料叶片有限元模型，计算了考虑动力刚化及阻尼效应影响下的固有频率和振型，揭示了动力刚化效应对叶片固有频率的影响规律；并结合坎贝尔图，对叶片进行了共振分析，为叶片的结构设计及优化提供了参考依据。

英文摘要：

The structural dynamic behavior of large wind turbine blade is Of importance for wind turbine safe operation. Based on modern flexible multi-body dynamics and finite element analysis method, the finite-element model of 5 MW wind turbine blade with composite structure was established and its natural vibration characteristics were analyzed in this paper. The natural frequencies and modal shapes with the effects of dynamic stiffening and damping were calculated. Accgrding to the calculated results, the rule of dynamic stiffening effect on blade was obtained. Finally, the resonance characteristics of the blade were analyzed with Campbell chart. These provide ,the reference basis for blade design and optimization.