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风力机运行在复杂多变的自然环境之中,风是影响风力机气动特性和振动特性的最直接因素,高风速及风速突变将诱发风力机更强的气动载荷。为探究风力机柔性部件在高风速及突变湍流风作用下的振动特性,以NREL(美国国家能源部可再生能源实验室)实测数据为湍流风数据源,并添加相干结构描述风速突变,以NREL 1.5 MW近海桩柱式风力机为样机,建立基于Kane方法的风力机结构动力学模型,并使用假设模态离散化方法对其进行柔性化,而后将该模型与风场和气动力模型一起组成气-弹相互耦合系统动力学模型,分别研究了风力机叶片和塔架的结构动力学响应。结果表明:相干结构的添加可使基础湍流风具有更大的风突变以及更高的湍流强度;额定风速附近,叶尖位移体现为挥舞,切出风速附近,叶尖位移同时体现为挥舞和摆振;相干结构的添加使得叶片和塔架振动加速度成倍增加。
Wind turbines operate in a complex and ever-changing natural environment. Wind is the most direct factor that affects the aerodynamic characteristics and vibration characteristics of wind turbines. High wind speed and sudden changes in wind speed will induce stronger aerodynamic loads on the wind turbines. In order to investigate the vibration characteristics of flexible components of wind turbine under high wind speed and turbulent turbulence, the measured data of NREL (the US Department of Energy’s Renewable Energy Laboratory) were used as the data source of turbulent wind, and the coherent structure was added to describe the wind speed abrupt changes. The NREL 1.5 MW offshore wind turbine as a prototype, the dynamic model of wind turbine structure based on Kane method is established, and the modal discretization method is used to make it flexible. Then the model is combined with wind field and aerodynamic model - Dynamic Coupling System Dynamics Model, the structural dynamic responses of wind turbine blade and tower are studied respectively. The results show that: the addition of coherent structure can make the basic turbulent wind have greater winds mutation and higher turbulent intensity; near the rated wind speed, the tip displacement manifests as waving and cutting out near the wind speed, and the tip displacement simultaneously manifests as wave and pendulum Vibration; the addition of coherent structure makes the blade and tower vibration acceleration multiplied.