叶片质量不平衡对基础环式风机基础服役性能影响研究

Effect of Blade Mass Imbalance on the Service Performance of Wind Turbine Foundation with Foundation-ring

风力发电机叶片长期暴露于恶劣的高空环境,极易产生质量不平衡故障,对风力机的稳定可靠运行影响极大。传统的叶片质量不平衡研究主要集中于对风力发电机组功率和塔筒的分析。基础环式基础广泛应用于风力发电机,在循环荷载作用下易发生损伤破坏。因此,基于叶素动量等理论建立考虑叶片质量不平衡故障的基础环式风机基础服役性能评估模型,模型利用解析方法计算质量失衡叶片对基础造成的附加荷载,结合平衡条件和连续性条件,选用大型有限元软件ABAQUS模拟分析叶片质量不平衡故障对风力机基础应力、疲劳寿命以及侧壁混凝土裂缝发展规律的影响。结果发现:质量失衡叶片在水平方向对风力机基础疲劳寿命的影响最大,叶片质量失衡故障会加快基础混凝土损伤过程,增加基础环的水平度,进而降低风力机基础整体服役的可靠性。此外,建议风力机发生较小叶片质量失衡损伤时通过降低转速维持风力机运行,并定期监测叶片质量失衡比。

The wind turbine blades are exposed to the adverse high-altitude environment for a long time and are very prone to mass imbalance failure,which has a significant influence on the stable and reliable operation of the wind turbines.The previous blade mass imbalance studies mainly focus on the analysis of wind turbine power and tower.Foundations with foundation-ring are widely used in wind turbines,which are prone to damage under cyclic loading.Therefore,a service performance assessment model of wind turbine foundation considering blade mass imbalance failure was established based on blade element momentum theory.The additional load caused by the mass imbalance blade on the foundation was calculated using the analytical method.Combined with the equilibrium con⁃dition and continuity condition,the large finite element software ABAQUS was selected to simulate the influence of the blade mass im⁃balance failure on the wind turbine foundation stress,fatigue life,and concrete crack development.The results show that the mass im⁃balance blade in the horizontal direction has the greatest impact on the fatigue life of wind turbine foundation,blade mass imbalance failure will accelerate the foundation concrete damage and increase the level of the foundation ring,which in turn reduces the reliability of the overall service of the wind turbine foundation.Furthermore,it is recommended to maintain the turbine operation by reducing the rotational speed and to monitor the blade mass loss ratio regularly when small blade mass imbalance damage occurs in the turbine.