风力发电机叶片折断对叶片动力影响分析

Influence Analysis of Wind Turbine Blade Breaking on Blade Dynamics

为了分析风力发电机叶片突然折断对其他叶片的影响规律,通过有限元模拟得到了正常风载作用时叶片的易折断部位,分析了叶片不同折断部位对其他2个叶片的影响,通过理论计算确定其所受荷载。建立简化的风力发电机叶片模型,将理论分析得到的荷载值分解为轴向力与切向力,并施加于模型中。当风力发电机顺时针旋转时,分析旋转不同角度对其他叶片的动力影响。结果表明:叶片旋转到60°(初始位置为x轴正半轴方向)从根部折断时,顺时针方向靠近的叶片(叶片1)最大应力集中于下叶根部位;当叶片旋转到150°时,逆时针方向靠近的叶片(叶片2)的最大应力集中于下叶根部位。叶片旋转到60°从中部折断时,最大应力集中于叶片1的下叶根部位;当该叶片旋转到330°时,最大应力集中于叶片2的下叶根部位。建议及时更换受损叶片,以降低折断叶片对其他叶片安全运行的影响程度。

In order to study the influence of suddenly breaking of wind turbine blades on other blades,this paper uses finite element simulation to obtain the vulnerable parts of the blades when they are subjected to wind load.By considering the influence of different fracture parts of the blades on the other two blades,its carrying load is calculated through theoretical calculation.Establish a simplified wind turbine blade model,and the load value obtained by theoretical analysis is decomposed into axial force and tangential force and is applied to the model.When the wind turbine rotates clockwise,the dynamic effects on other blades when rotating to different angles are investigated.The results show that when the blade breaks from the root and rotates to 60°,the maximum stress of the blade close to the clockwise direction(blade 1)is concentrated on the root of the lower blade;when the blade rotates to 150°,the maximum stress of the blade close to the counterclockwise direction(blade 2)is concentrated on the root of the lower blade.When the blade breaks from the middle and rotates to 60°,the maximum stress is concentrated on the lower root of the blade 1;when the blade rotates to 330°,the maximum stress is concentrated on the lower root of the blade 2.It is recommended to replace damaged blades in time to reduce the impact of broken blades on the safe operation of other blades.