计及齿轮全柔性的风电机组传动链有限元建模及扭振特性分析

大功率风电机组传动链关键部件柔性直接影响机组扭振特性及疲劳寿命,提出考虑齿轮柔性与啮合柔性的传动链有限元建模及扭振特性分析。首先,基于实际双馈风电机组传动链结构、材料属性与几何参数,考虑齿轮箱内齿轮柔性与齿轮啮合柔性,结合叶片、轮毂、主轴和发电机转子,建立风电机组传动链多柔体有限元模型。其次,基于有限元模态分析理论,提出一种基于矢量位移云图筛选扭振频率的分析方法,获取计及齿轮全柔性影响的风电机组中、低频范围的扭振模态,并与不同传动链模型结果进行比较,验证该文所建模型的有效性。最后,分别分析不同齿轮柔性和齿轮啮合柔性对传动链扭振频率和模态的影响。结果表明,该文所建模型不仅能反映传动链扭振固有的低频频率,而且能反映弯扭耦合产生的中频扭振频率,且相比齿轮啮合柔性,齿轮柔性系数影响传动链高频扭振特性明显。

FINITE ELEMENT MODELING AND TORSIONAL VIBRATION ANALYSIS OF WIND TURBINE DRIVETRAIN CONSIDERING FULL FLEXIBILITY OF GEARS

The flexibility of the key components of the high-power doubly-fed wind turbine drivetrain directly affects the torsional vibration characteristics and fatigue life of the drivetrain. The finite element modeling and torsional vibration analysis of the drivetrain considering the flexibility of the gear and the gear meshing are proposed. Firstly,based on the actual double-fed wind turbine drivetrain structure,material properties and geometric parameters,considering the gear and gear meshing flexibility in the gearbox,combined with the blade,hub,main shaft and generator rotor,a multi-flexible finite element model of the wind turbine drivetrain is established. Secondly,based on the finite element analysis theory,an analysis method based on vector displacement cloud map is proposed to screen the torsional vibration frequency,and the torsional vibration mode of the low-frequency and intermediate-frequency of the wind turbine with the full flexibility of the gear is obtain. Compared the results with different drivetrain models to verify the validity of the model built in this paper.Finally,the effects of different gear and gear meshing flexibility on the torsional vibration frequency and mode of the drivetrain are analyzed. The results show that model built in this paper can not only reflect the low natural frequency of the torsional vibration of the drivetrain,but also reflect the intermediate frequency torsional vibration frequency generated by the bending and torsion coupling. Compared with the gear meshing flexibility,the gear flexibility coefficient has more influence on the high-frequency torsional vibration characteristics of the drivetrain.