风力发电机塔架风致疲劳寿命评估

Evaluation of wind induced fatigue life of wind turbine tower

基于5 MW风力发电机系统对风力发电机结构的疲劳寿命进行了研究。首先应用ANSYS软件建立了风力发电机的多尺度有限元模型,根据圣维南原理,确定了与土相连的塔体实体模型的高度,并确定门洞出单元尺寸;然后采用Davernport谱和谐波叠加法模拟风荷载,进而结合所模拟的风荷载开展动力时程分析,得到所求关键点的应力时程;最后基于时程结果结合雨流计数法和Pelmgren-miner线性累积损伤法则对风力发电机结构关键部位的疲劳寿命进行了分析,该方法充分考虑了风荷载的模拟和热点应力法等。研究表明,疲劳分析方法可有效的估算水平轴风力发电机结构的疲劳损伤问题,相关结论可为大型风力发电机结构的疲劳寿命预测提供帮助。

This paper studied the fatigue life of the wind turbine structure based on 5MW wind generator system. First, ANSYS software was used to establish the multi-scale finite element model of the wind turbine, the height of the tower body entity model connecting to the soil was determined according to the principle of Saint Venant, and the unit size of the door opening was also determined. Secondly, the Davernport spectrum and harmonic superposition method were used to simulate the wind load, and then the dynamic time analysis of the simulated wind load was carried out to obtain the stress of the hot spot. Finally, based on the rain flow count method and the result of the schedule, the Pelmgren of miner linear cumulative damage rule of the wind turbine fatigue life of key parts were analyzed, which took full consideration of the wind load simulation and hot spot stress method. Studies show that the fatigue analysis method can effectively estimate the fatigue damage of horizontal axis wind turbine structure problem, the related conclusions can provide help for the fatigue life prediction of the large wind generator structure.