Tonality evaluation of wind turbine noise by filter-segmentation

Wind turbine (WT) noise is one of the major hindrances for the widespread use of wind energy. Noise tone can greatly increase the annoyance factor and the negative impact on human health. The national standard for measuring WT noise tonality IEC 61400-11 does not ensure consistency and accuracy in the tonality analysis of strongly non-stationary noise. The aim of this study is to explore a new tonality evaluating methodology that is based on noise separation and stationary processing. An effective Gabor filtering method is proposed to remove background noise embedded in the sound signal of operating wind turbine. One-minute wind-turbine sound signal without background noise is optimally divided into relatively stationary sub-segments, by making full use of the close relationship between the wind-turbine rotor speed and the tonal noise emitted from WT. The proposed method’s theoretical advantages over conventional evaluation in IEC are illustrated. Results of experiments for GOLDWIND 77/1500 WT are presented, which show the capability of the proposed methodology.     

风力发电机齿轮箱测试内齿圈异响分析

对齿轮箱做振动测试和分析,找到齿轮箱异响呈现的特性,为齿轮箱故障诊断提供依据。     

基于风速预测的风电机组自动解缆优化方案研究

针对当前风电机组解缆控制存在的问题,首先对目标风电场的解缆情况进行了统计分析,指出优化解缆控制方案的必要性;然后提出了基于PSO-LSSVM模型的超短期风速预测方法,实现了对未来30 min内平均风速的预测;最后提出了基于超短期风速预测的风电机组自动解缆优化方案,并对目标风电场的解缆控制方案进行了优化升级。测试结果表明PSO-LSSVM模型与LSSVM模型相比具有更高的预测精度,能够满足解缆控制的要求;优化后的解缆控制方案有效降低了因解缆造成的电量损失,具有良好的工程应用价值。     

风力发电机的造型设计

通过对风力发电机的形态设计学研究、空气动力学方面的研究以及机舱内的人机工程学研究从而设计出不仅造型美观而且能提高整体运行的效率、使用寿命的风力发电机。     

Modeling of oscillating wind turbine

The operating capacity of wind turbines of a new type is considered in which autorotation of the wind-receiving surface is replaced by oscillations of small amplitudes. It is shown that an oscillating wind turbine in its utilization of wind power falls between a three-blade Savonius rotor and a Darye rotor. The advantage of oscillating wind turbines is the possibility of significantly increasing the area of the wind-receiving surface without a noticeable growth of the area needed for the placement of the unit.     

下风向风力机风轮直径的最优解

针对现有风轮直径计算精度的不足,根据提出的下风向风力机风轮扫掠面积上能量分布数学模型,推导出了考虑风剪切与塔影效应在内的精确能量获取计算式。结合具体算例,对风轮直径的3种不同计算格式分别予以求解。计算结果表明:风剪切对风力机风轮直径的影响甚小,塔影效应影响明显,塔架高度影响最大;风轮直径与塔架直径近似成线性关系;塔架高度存在极值;存在满足能量输出要求的最优尺寸匹配关系。     

柔性桨风力机理论研究

推导出了柔性桨风力发电机输出功率表达式,讨论了此种风力机6个参数对输出功率的影响。     

提高风力机组可靠性方法研究

为了提高风力机组的安全可靠性，在分析了近年来国内外风力机组实际运行情况的基础上，将引起故障的因素归结为外部环境、组件故障和人为失误3个方面，然后分别从应对外部环境影响、保障风力机组内部安全、减少人为控制失误、定期日常检修维护4个方面结合实际案例进行了论述并总结了相应的解决措施。研究结果表明，该研究为进一步进行风力机组优化设计奠定了基础。     

风电机组的照明配电系统设计

为了解决风电机组安全运行和设备维修的照明问题,在对风电机组的照明灯具、照度和应急电源进行计算与分析的基础上,建立了照明配电系统和风电机组之间的关系,提出了采用正常照明、局部照明和应急照明三级照明设置方法,并进行了计算和研究.风电场现场的应用结果表明,该系统稳定、可靠,能满足现场需要.     

浅谈风力发电机组的监控系统

风力资源丰富的地区一般都是在沿海地区、海岛、海上、山口或草原地区,针对分散安装的风力发电机组要求能够实现无人值守运行和进行远程监控,因此对风力发电机组控制系统的自动化程度和可靠性提出了极高的要求。本文详细介绍了大型风力发电机组监控系统的基本结构、数据监测内容、信息通讯方式、控制软件功能特点及系统的抗干扰措施等。     

风力发电机叶片动力学研究与分析

根据风机气动相关理论,进行叶素空气动力学特性分析,并给出叶片气动力的计算表达式,采用ANSYS有限元分析软件对风机叶片模型进行振动模态分析,计算了叶片的固有频率、各阶振型图,为避免叶片发生共振、提高叶片使用寿命提供了分析方法。     

风力发电机组轮毂结构优化

以中国自行设计的某MW级风机轮毂为研究对象,先对轮毂进行拓扑优化,验证拓扑结构,然后对轮毂进行自由尺寸优化,给出一种新型的轮毂结构,使得轮毂重量减少18.6%.优化后的轮毂不但节省材料的消耗,而且使得轮毂强度增加51.4%,疲劳寿命满足使用要求.     

Laboratory-scale experiments on wind turbine nacelle movement estimation

The effect of nacelle motion should be considered when calculating the wind speed relative to the wind turbine structure, which is essential in wind turbine control and performance testing. A Kalman filter approach is applied to estimate the nacelle motion of a wind turbine. Information from several accelerometers and strain gauges which are installed on the wind turbine tower is combined with the Kalman filter. An optimization algorithm is used to choose the optimal locations for strain gauge and accelerometer installation. A laboratory-scale experimental rig which mimics the tower and nacelle of the wind turbine is constructed to evaluate the performance of the proposed estimator algorithm. The usefulness of the proposed algorithm is validated by these laboratory-scale experimental results.     

基于LabVIEW的双馈风力发电机组在线谐波分析研究

针对双馈风力发电机组在并网运行时,其电力电子变流装置将向电网注入大量谐波电流的问题,将基于LabVIEW的在线谐波分析技术应用到双馈风力发电机组的谐波监测分析中。开展了针对双馈风力发电机组注入电网谐波的傅里叶分析和小波包分析,提出了将傅里叶变换与小波包变换联合使用的方法;在LabVIEW上搭建了仿真平台,对双馈风力发电机组可能存在的谐波进行了仿真分析试验。试验及研究结果表明,对于平稳信号与非平稳信号进行谐波分析时,将傅里叶变换与小波包变换联合使用,两者的效能得到明显的提高,优于单独使用傅里叶变换或小波包变换,且可更准确地获取基波和谐波的实时波形与频域特性,谐波定位更准确,为谐波补偿提供了更可靠、准确的信息。     

垂直轴风力机流场模拟计算网格划分研究

垂直轴风力机是一种全风向工作、结构简单可靠的风力发电能量转换机械,用CFD软件对其流场进行分析、研究,最为关键的是对数值模型进行网格划分。针对垂直轴风力机流场的特点,结合实践运用情况,给出了其网格划分的基本方法及注意要点。     

基于神经网络PID的变速变桨距控制设计

在风力发电中,为了提高风力发电的能量转换效率对风力发电机进行变速变桨距控制,按照所需要的功率系数值确定所需要的变桨角度,以保证功率的稳定.本文研究利用神经网络PID控制器作为变速变桨距系统的控制器.在风速低于额定风速时,采用的是变速控制,此时风能效率高于采用失速控制风电机组的风能效率,具有优化的气动特性;在风速高于额定风速的情况下,根据风速的变化调整桨叶节距角,从而调节发电机的输出功率,使风力发电机组的输出功率保持稳定.最后,利用Simulink构建整个控制系统,对系统进行Matlab仿真.结果表明,使用神经网络PID控制的风力发电系统在风速从额定风速到切出风速时,相对失速控制风电机组,采用变桨距控制风电机组的功率恒定,发电品质较好.     

兆瓦级风力发电机组叶片设计

研究了兆瓦级风力发电机叶片翼型建模的方法,应用UG、Matlab建立叶片实体模型,提高了建模效率,为后续结构强度、叶片的力学特性计算等进一步分析奠定了基础。     

基于有限元模拟的风力机塔架优化

塔架是风力发电机的重要受力部件.首先利用Patran/Nastran对塔架进行静力、模态、稳定性有限元分析,然后将有限元模拟结果与优化软件iSIGHT相结合,利用遗传算法对塔架各节壁厚做优化设计,比较不同约束条件得到的优化结果.通过优化分析可以达到在满足结构性能要求的条件下减轻塔架重量、降低成本的目的.     

Numerical and experimental investigation of wind loadings on vertical axis wind turbine blade deflection

This work focuses on experimental and numerical investigation of the deflection on VAWT blade surface against the high measured wind speeds that were simulated in FLUENT to obtain the corresponding static forces. The effect of forces, blade setting angle and thickness to chord ratio along with their combined effects on deflection were assessed experimentally and numerically. Three airfoils of gradually increasing thickness to chord ratio, NACA 0015, 0021 and 4412, were selected along with three levels of forces and tested at 5°, 10° and 15° of blade setting angle. A 3³ factorial experimental design was used to perform experiments and Analysis of variance (ANOVA) confirmed that individual effects of force and thickness to chord ratio were the most significant factors while blade setting angle had lesser significance on deflected values. However, interactive effects of these parameters were significant. Minimum deflections were observed in the range of 0.25-0.28 mm on NACA 0021 at 3 kg force in combination with all blade setting angles. Maximum observed value of defection was 1 mm, which occurred at 9 kg force at 5°, 10° and 15° of blade setting angle on NACA 0015 and 4412 airfoil shapes. The results ensure that the blade structure remains stable at 9 kg which corresponds to 20 m/s wind speed without affecting the performance. The deflections obtained from Finite element method were compared with experimental results and found in good agreement with each other.

     

风电机组传动链的动力学仿真研究

针对风电机组传动链在工作转速范围内的扭转共振问题,基于GL2010标准,结合动力学仿真软件SIMPACK和有限元分析软件ANSYS,建立了某兆瓦级风电机组传动链的多柔体动力学仿真模型,并使用模态分析方法对传动链动力学仿真模型进行了频域响应分析,基于2D坎贝尔图和模态能量分布图,筛选出了传动链的潜在共振点,最终通过时域仿真分析,对相关部件的加速度进行了傅里叶变换,进一步验证了该潜在共振点是否是实际的危险共振点。研究结果表明,该机型风电机组传动链不存在危险的共振频率,在工作转速范围内能够安全稳定地运行;该方法可为风电机组的稳定性和可靠性设计提供依据。