兆瓦级风力机液压变桨执行机构疲劳寿命分析

Fatigue life analysis of the hydraulic variable-pitch actuator for MW wind turbine

文章建立液压变桨执行机构有限元模型,通过静力学分析得到液压缸与活塞杆的应力分布结果,动力学分析得到液压缸与活塞杆的疲劳载荷谱,将静力学、动力学分析结果及修正后的液压缸及活塞杆材料S-N曲线导入到MSC.Fatigue软件得到风力机液压变桨执行机构疲劳寿命云图。在此基础上,对一台2 MW风力机液压变桨执行机构,对比分析材料及载荷频率改变对液压变桨执行机构疲劳寿命的影响程度,并对液压缸与活塞杆最易受损位置进行了结构优化。研究结果表明,对液压变桨执行机构的设计,尤其在提高液压变桨执行机构甚至风力机整机疲劳寿命方面具有重要指导意义。

In this paper,the finite element model of the hydraulic variable-pitch actuator is built, the stress distributions through statics analysis and the fatigue load spectrum through dynamics analysis are obtained for the hydraulic cylinder and piston rod, and the revised material S-N curve of the hydraulic cylinder and piston rod besides the statics and dynamics analysis results are imported into the MSC.Fatigue software so that the hydraulic variable-pitch actuator fatigue life contours are obtained. On this basis, for a 2 MW wind turbine hydraulic variable-pitch actuator, the influence of material and loading frequency change on fatigue life is compared and analyzed for the hydraulic variable-pitch actuator,and the most easily damaged position of the hydraulic cylinder and piston rod is optimized by structure.From the design point of view, The research results have important guiding significance to improve the hydraulic variable-pitch actuator fatigue life and even wind turbine.