针对风电装备的全叶片伞型斜轴折叠叶轮结构及变桨原理

Wind power has become an important green energy. The core technology of wind turbine is how to obtain high efficiency wind energy by blade and the real-time control of system. At present only one active regulation technology is pitch, which is on basis of blade spin on root. The project will focuses on the academic research hot point of pitch to study the mechanical structure and pitch principle of innovative umbrella-type rotor with oblique-axis-based folding for wind turbine. The innovative umbrella-type structure can separate the two functions of pitch and bearing with simplicity characteristics of pitch and force transmission, involving with aerodynamic principles of the oblique folding blade and the kinematics of umbrella-type pitch. Base on theoretical analysis, model wind tunnel tests, numerical simulation and real wind tests of prototype, the mechanical principle of umbrella-type pitch are studied systematically, which concern the structure of rotor, the kinematics and dynamics of the folding blade movement mechanism, the fluid-solid coupling analysis method, the aero-elastic-wake coupling behavior and the characteristics of the eddy current during the folding process, the rotating mechanics of folding pitch blade, and the static / vibration /real-wind-test of experimental prototype. The objectives of this project are fundamentally to change the pitch method and the manner of bearing for the existing wind blades, and to provide theoretical support for the comprehensive high efficiency and lightweight of wind turbine equipment.

风电已成为重要的绿色能源，风机的核心技术之一就是如何高效地通过叶片来捕获风能并进行实时的控制与调节，目前唯一的主动调节技术就是变桨，且只有基于叶片根部回转的自旋转这一种方式。本项目针对风电的变桨调节这一国际学术研究热点，提出全叶片斜轴折叠以及伞型铰接拉杆支撑的结构形式，开展新型变桨原理的研究，将变桨与承力这两个功能分离，使得变桨方式更简洁、传力路径更简单，解决叶轮变桨中的变桨与承力所带来的突出问题。项目将采用变桨理论分析、模型风洞试验、数值仿真以及试验样机测试的研究手段，系统研究全叶片伞型斜轴折叠叶轮的结构形式、机械及力学原理、气流-叶片之间流-固耦合分析的高效计算方法、以及进行全叶片伞型斜轴折叠变桨的非线性气弹行为分析，并对全叶片伞型斜轴折叠模型样机进行测试。可望发展一种新型的风机叶轮变桨结构及原理，以改变现有风机的变桨及承力方式，为风机叶轮结构的轻量化设计提供一种技术途径及理论支持。

随着风电行业的不断发展，为提高风能利用效率，降低度电成本，风电机组逐渐向大型化、海上化的发展趋势，随之而来的叶片轻量化设计、变桨调节、风电机组气动性能、尾流特征、以及风电场优化的深入研究成为当前风电领域的研究重点。本项目通过风洞实验和数值仿真方法，系统研究了风电机组的气动、尾流及载荷特征规律，获得了海上浮式平台纵荡与横荡运动对风电机组气动特性的影响规律，分析了垂直轴风电机组协同效应的机理，建立了偏航风电机组的尾流模型，提出了基于偏航尾流叠加的风电场偏航优化策略。构建了适用于多风电机组分析的柔性致动线方法（FALM）计算模型，研究了风电机组的气弹-尾流耦合行为。在此基础上，进一步提出了应用于水平轴下风向风电机组的向前折叠式斜轴变桨风轮结构，以降低风电机组叶片的载荷与质量；提出了应用于垂直轴风电机组的新型斜轴变桨概念及斜轴变桨结构原理设计，可实现风力发电机功率调节，并具有操作方便、易于工程实施等优点。本项目研究工作对风电机组大型化、轻量化和风电场优化具有实际应用意义。