复杂荷载环境下海上风力机的建模及动力学特性分析  

Dynamics modeling and analysis of offshore wind turbines under complicated loads

作　　者：王青占 赵建中[1] 郭兴明[1] 

机构地区：[1]上海大学上海市应用数学和力学研究所,上海200072

出　　处：《上海大学学报（自然科学版）》2016年第5期573-585,共13页Journal of Shanghai University:Natural Science Edition

基　　金：国家重点基础研究发展计划(973计划)资助项目(2014CB0462003)

摘　　要：通过分析处于海风、海浪、海流、土壤力等复杂荷载作用下的海上风力机支撑结构,采用赫维赛德阶跃函数和狄拉克δ函数建立了连续统一的、顶端带有集中质量块的悬垂梁风力机动力学模型.基于对控制方程的Galerkin截断,得到离散化的常微分方程组,使用四阶Runge-Kutta方法求解,得到了模型的动力学行为特性云图曲线.通过悬垂梁风力机模型的时程曲线、庞加莱映射对风力机模型进行动力学分析,给出了位移和速度的幅值随激振力频率变化的幅频特性曲线,并研究了垂向激振、自重、变刚度参数对风力机结构振动特性及其稳定性的影响.By analyzing the structure and complexity of offshore wind turbines （OWTs）, a beam model with free end carrying a concentrated mass body was built to analyze dynamical characteristics of OWTs subject to adverse working environment loads. Factors including vertical excitation, self-weight, rotary inertia and variety of stiffness were considered to study the effect on offshore wind turbines. A general and uniform governing equation was built by taking advantages of the Heaviside step function and Dirac delta function. Based on the Galerkin truncation and the Runge-Kutta time discretization, numerical solutions of the kinematic governing equation were obtained. By comparing with the analytical solution under specified conditions, validity of the method was checked. The time history of the beam＇s free end was chosen to represent motion of the beam. Based on the steady tirae history of the beam, a Poincare map was constructed to study its periodic motion. Furthermore, an amplitude-frequency curve was given to find the dangerous frequency range where OWTs exist.

关 键 词：海上风力机 变轴力 复杂荷载 变刚度 动力响应 

分 类 号：TH43[机械工程—机械制造及自动化]