风电叶片联接结构常规强度校核方法

风电叶片联接结构是联接叶片和轮毂的唯一结构，其安全性设计非常重要。文中介绍了风电叶片“T”型叶根联接结构的常规强度校核方法。     

风电叶片固有频率相关性分析新方法

为进行三维风电叶片振动系统固有频率相关性分析,采用MATLAB和ANSYS共同建立了风电叶片三维有限元参数模型,并分析了叶片固有振动特性.考虑系统随机结构参数对风电叶片固有振动的影响,运用将Monte Carlo与ANSYS相结合的方法对叶片固有振动特性进行相关性分析,进而判断其对随机结构参数的敏感性,形成了一种叶片结...     

大型风电叶片缺陷及其无损检测技术研究

文章介绍了大型风电叶片在生产制作、转运以及服役过程中产生的主要缺陷和损伤形式,讨论了静态无损检测技术和动态监测技术的特点及其在风电叶片缺陷检测领域的必要性,并对其优、缺点进行了比较和评价。     

风电叶片的五年之忧——某风电场风电机组叶片定检、维护、维修统计分析报告

自2006年6月第一台国产1.5MW风电机组成功下线,拉开我国大风电时代的帷幕伊始,大功率叶片已风风光光地走过5载有余。在这辉煌的历程中,风电机组在使用、维护方面也曾出现过一些波折,如叶片服役初期折断,击毁机舱、毁坏塔筒导致风电机组倒塌的事件;横向裂纹、前后缘开裂等隐患。针对采取什么样的措施、投入多少费用,才能保证叶片在20年的设计寿命中,保持良好的功率产出状态这一难题,业内各界始终存     

扩博智能收购Finetune——以数据能力领跑风机后运维市场

正2020年8月19日,上海-扩博智能Clobotics宣布收购全球领先的风机叶片运营维护服务提供商Finetune公司。此次收购,将进一步巩固扩博智能集团Clobotics在全球风机后运维市场上的领先地位,结合其以数据分析能力见长、以全自动无人机为载体的风电叶片维修维护大数据平台,扩博智能将继续领跑全球风机后运维市场。     

GE着手开发织物型风机叶片

<正>2013年3月19日,GE全球研发中心首席工程师Wendy Lin在新技术发布会上说:"我们正在开发的织物型叶片将更加强劲而柔韧、更易于安装和维护。这正好描绘了一条清晰的路径,将使风电成本甚至比化石燃料发电更具竞争力。"GE认为,这种新型设计将使风机叶片成本降低25%到40%,使得在没有政府补贴的情况下,风电与化石燃料发电成本相近。GE的研究将聚焦于叶片结构上的织物的使用,将其包裹在金属结构上,就好像鱼骨架。织物会被拉紧并蒙在骨架上,从而满足风机叶片运行的需求。受设计、生产、安装和运输的限制,目前的技术很难让风机转子的直径超过120 m。更宽、更长的风机叶片更难搬运和操     

浅析退役风电叶片的回收与再利用

风电设备退役潮即将到来,退役风电叶片数量庞大,以掩埋或焚烧方式处理会造成资源浪费和环境污染,有必要研究以更具经济价值的方式将废弃风电叶片进行回收再利用。目前,风电叶片主流的回收方法及利用形式各有利弊,回收再利用技术需要持续优化,需要制定推广风电叶片回收的相关标准,促进退役风电叶片的循环利用。     

大型水平轴式风电叶片的结构设计

风电叶片是风力发电设备的关键部件之一,其制造成本占总成本的20%～30%.叶片结构是叶片捕获风能的保证,并直接影响风力发电设备的运行寿命.因此,叶片结构设计的好坏在很大程度上决定了风力发电设备的可靠性和利用风能的成本.文章从材料、结构形式、铺层设计、结构分析等4个方面详细地阐述了风电叶片结构的设计技术.     

DTR E240E风电叶片用环氧胶黏剂的研制

文章在综述风电叶片用环氧胶黏剂国内外研究进展,风电叶片在环氧胶黏剂的性能要求的基础上,采用固化剂改性的方法研制出DTR E240E系列风电环氧胶黏剂.对该胶黏剂的工艺性能、浇铸体力学性能、粘接性能及耐蠕变性能进行了详细的表征.结果表明DTR E240E系列风电环氧胶黏剂拥有良好的综合性能,完全满足风电叶片的要求.DTR E240E系列风电环氧胶黏剂成功地应用于1.5 MW和2.0 MW风电叶片上.     

废弃风电叶片材料回收与再制造技术的研究进展

首先，介绍国内外风电叶片的使用规模和退役风电叶片趋势，阐述国际上通用的退役风电叶片处置方式（堆放、掩埋、回收利用）及其优缺点；其次，系统介绍废弃叶片材料的典型回收利用方法，即机械回收、热回收和化学回收，比较3种典型回收利用方法的技术特点；然后，总结了利用退役风电叶片进行产品再制造的典型案例，包括制备再生复合材料板材、制造混凝土骨料、制备3D打印耗材等；最后，针对风电材料常见的玻璃纤维复合材料、碳纤维复合材料等的难切削性能，介绍风电叶片回收加工技术与装备，包括切割加工技术和装备、破碎及粉碎加工技术和设备等。     

基于NX二次开发的大型风机桨叶参数化建模

风机桨叶作为捕捉风能的关键零部件,其复杂表面是三维建模的难点.以2 MW风机桨叶为依托,对桨叶参数化建模进行研究,开发出基于NX的桨叶参数化建模程序,用户只需输入风机基本参数可快速生成桨叶三维模型.缩短了建模周期,提高了模型精确度,为桨叶的气动外形优化和模态分析提供三维模型.     

Measurement of stress on blade of NEDO's 500 kW prototype wind turbine

Among the components used in a wind turbine the blade is the most damageable component for fatigue caused by atmospheric turbulence. Therefor it is necessary to understand the stresses which are occurring on the operating wind turbine blade. We installed a prototype 500 kW wind turbine developed by the NEDO (New Energy and industrial technology Development Organization) in Tappi Wind Park where is very complex terrain, to study its performance, reliability and durability. Some measurements and data analysis of the blade stress have been done. In this paper, some results of the stress measurement are presented.     

Assessment of optimum tip speed ratio in wind turbines using artificial neural networks

Wind turbine blade design depends on several factors, such as turbine profile used, blade number, power factor, and tip speed ratio. The key to designing a wind turbine is to assess the optimal tip speed ratio (TSR). This will directly affect the power generated and, in turn, the effectiveness of the investment made. TSR is suggested to be taken between 7 and 8 and in practice generally taken as 7 for a 3-blade network-connected wind turbine. However, the optimal TSR is dependent upon the profile type used and the blade number and could fall out of the boundaries suggested. Therefore, it has to be assessed accordingly. In this study, the optimal TSR and the power factor of a wind turbine are predicted using artificial neural networks (ANN) based on the parameters involved for NACA 4415 and LS-1 profile types with 3 and 4 blades. The ANN structure built is found to be more successful than the conventional approach in estimating the TSR and power factor.     

大型风力发电机组独立桨叶控制系统

设计出独立桨叶控制系统的机构方案，依据空气动力学分析，提出模糊控制结合以桨叶空间方位角作为主体因素的加权系数的控制策略，建立了系统模型，仿真结果表明，在风速高于额定风速时，作用在桨叶上的负载波动大为减小，输出功率维持在额定功率附近。     

风力机叶片动力特性实验台设计

设计开发了一种风力机叶片动力学特性实验台,可以进行风力机叶片的静载荷实验、模态测试、叶片损伤测试、模拟桨叶结冰附着物载荷实验、桨叶疲劳载荷实验以及破坏性实验等。介绍了实验台的设备组成、结构特点以及该实验台的主要功能,在实验台上进行了风力机叶片的静态载荷实验和模态测试,得出了实验用风力机叶片的六阶模态参数,利用MAC、MOV两种模态判定准则对试验结果进行了验证。     

Combining economic and fluid dynamic models to determine the optimal spacing in very large wind farms

Wind turbine spacing is an important design parameter for wind farms. Placing turbines too close together reduces their power extraction because of wake effects and increases maintenance costs because of unsteady loading. Conversely, placing them further apart increases land and cabling costs, as well as electrical resistance losses. The asymptotic limit of very large wind farms in which the flow conditions can be considered ‘fully developed’ provides a useful framework for studying general trends in optimal layouts as a function of dimensionless cost parameters. Earlier analytical work by Meyers and Meneveau (Wind Energy 15, 305–317 (2012)) revealed that in the limit of very large wind farms, the optimal turbine spacing accounting for the turbine and land costs is significantly larger than the value found in typical existing wind farms. Here, we generalize the analysis to include effects of cable and maintenance costs upon optimal wind turbine spacing in very large wind farms under various economic criteria. For marginally profitable wind farms, minimum cost and maximum profit turbine spacings coincide. Assuming linear‐based and area‐based costs that are representative of either offshore or onshore sites we obtain for very large wind farms spacings that tend to be appreciably greater than occurring in actual farms confirming earlier results but now including cabling costs. However, we show later that if wind farms are highly profitable then optimization of the profit per unit area leads to tighter optimal spacings than would be implied by cost minimization. In addition, we investigate the influence of the type of wind farm layout. © 2016 The Authors Wind Energy Published by John Wiley & Sons Ltd     

Wind turbine aerodynamics and loads control in wind shear flow

Wind turbine is subjected to some asymmetrical effects like wind shear, which will lead to unsteady blade airloads and performance. Fatigue loads can lead to damage of turbine components and eventually to failures. It is evident that the variation of the velocity over the rotor disc has an influence on the blade and introduces both flap-wise and edge-wise fatigue damage on the blade as a result of moment fluctuations in the two directions. The flap-wise moments on the blade are the origin of the rotor yaw and tilt moments which transmit to the turbine structure through the drive train to the yaw system and the tower. A lifting surface method with time marching free wake model is used to investigate the periodic unsteady nature in the wind shear. Individual pitch control (IPC) that is applied nowadays is the most advanced active control to reduce the fatigue. The blade airloads and performance of the turbine are also predicted under IPC control. It is found that IPC of the fluctuating blade root flap-wise moment can reduce the flap-wise fatigue damage remarkably while the blade root edge-wise moments are less sensitive to the varying blade pitch than the blade root flap-wise moments.     

Estimating the angle of attack from blade pressure measurements on the National Renewable Energy Laboratory phase VI rotor using a free wake vortex model: yawed conditions

Wind turbine design codes for calculating blade loads are usually based on a blade element momentum (BEM) approach. Since wind turbine rotors often operate in off‐design conditions, such as yawed flow, several engineering methods have been developed to take into account such conditions. An essential feature of a BEM code is the coupling of local blade element loads with an external (induced) velocity field determined with momentum theory through the angle of attack. Local blade loads follow directly from blade pressure measurements as performed in the National Renewable Energy Laboratory (NREL) phase IV campaign, but corresponding angles of attack cannot (on principle) be measured. By developing a free wake vortex method using measured local blade loads, time‐dependent angle of attack and induced velocity distributions are reconstructed. In a previous paper, a method was described for deriving such distributions in conjunction with blade pressure measurements for the NREL phase VI wind turbine in axial (non‐yawed) conditions. In this paper, the same method is applied to investigate yawed conditions on the same turbine. The study considered different operating conditions in yaw in both attached and separated flows over the blades. The derived free wake geometry solutions are used to determine induced velocity distributions at the rotor blade. These are then used to determine the local (azimuth time dependent) angle of attack, as well as the corresponding lift and drag for each blade section. The derived results are helpful to develop better engineering models for wind turbine design codes. Copyright © 2008 John Wiley & Sons, Ltd.     

基于应变模态的风机叶片损伤诊断研究

针对多种受损工况下的风机叶片损伤诊断问题,文章基于模态理论对受损前和受损后的风机叶片进行位移和应变模态分析。首先建立风机叶片的三维模型并对其进行有限元分析;然后模拟叶片两位置不同的损伤状况,比较各工况下位移模态曲线、应变模态曲线和应变模态差分曲线在受损前后的变化规律,进而对叶片进行损伤辨识;最后选取应变模态变化率和由差分曲线建立的直接定位损伤指标I_SMSD作为风机叶片损伤诊断指标,进一步辨别叶片的损伤程度。通过结构损伤前后模态频率、位移模态及应变模态参数的对比可以发现:在受损量不同的情况下,叶片模态频率损伤前、后变化较小,位移模态几乎没有产生变化;在受损区域应变模态及其差分曲线均有突变产生,裂纹的长度越大突变越明显。可将应变模态变化率和I_SMSD作为损伤诊断的特征参数,为风机叶片的预报维修提供参考。     

Study of ageing of laminates and its effects on wind turbine blade deflection

Some wind turbines have exceeded their nominal design service life and are continuing their operation with periodic inspections and maintenance. In the case of rotor blades, the reliability of the inspection is very limited because of the blade structure that comprises laminates and sandwich structures, which are very difficult to monitor. For this reason, wind farm owners are searching for technologies or approaches that will guarantee a safe operation of their wind turbines after the design life has elapsed. The main objective of this paper was to investigate whether detection of ageing of wind turbine blades using deflection as key parameter is feasible using commercial equipment. The paper is divided in three phases. In phase 1, the effect of ageing on a new UD‐0° glass fibre with high moduli was obtained. Using these results and bibliography data, a theoretical study was performed in phase 2 to determine the magnitude of blade deflection along its lifetime due to material ageing. Finally, in phase 3, in‐field deflection measurements where performed on a wind turbine blade to evaluate the utility and limitations of commercial equipment for the detection of blade ageing. It was concluded that material ageing could result in an increase in blade deflection under self‐weight that can be detected using commercial measurement equipment. These results can be used by wind farm owners in their O&M strategies to monitor blades over time and decide whether they should be repaired or replaced.