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。     

双级NGW型行星轮系的优化设计

按各级径向尺寸协调和外啮合接触强度相等的原则对双级NGW型行星轮系的总传动比进行优化分配 ,将双级行星轮系的优化设计转变成单级行星轮系的优化设计。以太阳轮、行星轮和内齿圈体积之和最小作为优化目标 ,建立了优化数学模型 ,应用复合形法求解数学模型择取最优参数方案。通过实例计算 ,取得了满意的结果     

Torque loss of type C40 FZG gears lubricated with wind turbine gear oils

Five fully formulated wind turbine gear oils were characterised. The gear oils have 320 ISO VG grade and different formulations: ester, mineral, PAO, PAG and mineral+PAMA.A back-to-back FZG test machine, with re-circulating power, was used and a torque-cell was included on the test rig in order to measure the torque loss. Eight thermocouples were included to monitor the temperatures in different locations of the test rig.Tests at 1.13, 2.26 and 6.79 m/s were performed for different FZG load stages: K1, K5, K7 and K9. Both gearboxes were jet-lubricated with an oil flow of 3 l/min. The input flow temperature was kept almost constant (80 ±1 °C).Friction generated between the meshing teeth, shaft seals and rolling bearing losses was predicted.     

Fault diagnosis for wind turbine planetary ring gear via a meshing resonance based filtering algorithm

Identifying the differences between the spectra or envelope spectra of a faulty signal and a healthy baseline signal is an efficient planetary gearbox local fault detection strategy. However, causes other than local faults can also generate the characteristic frequency of a ring gear fault; this may further affect the detection of a local fault. To address this issue, a new filtering algorithm based on the meshing resonance phenomenon is proposed. In detail, the raw signal is first decomposed into different frequency bands and levels. Then, a new meshing index and an MRgram are constructed to determine which bands belong to the meshing resonance frequency band. Furthermore, an optimal filter band is selected from this MRgram. Finally, the ring gear fault can be detected according to the envelope spectrum of the band-pass filtering result.     

Inverse dynamics of a planetary gear train for robotics

Recursive matrix relations concerning the geometric analysis, kinematics and dynamics of a Bendix wrist planetary bevel-gear train for robotics are established in the paper. The prototype of this mechanism is a 3-DOF system with seven links and four bevel gear pairs controlled by electric motors. Supposing that the rotational motion of the platform is known, an inverse dynamic problem is developed using the principle of virtual powers. Some relations and graphs for torques and powers of three actuators are determined.     

风力机齿轮箱布局的多目标可靠性优化设计

针对风力机齿轮箱布局设计中存在的问题,采用多目标可靠性优化设计方法,以风力机齿轮箱的箱体体积和齿轮体积最小化为设计目标,建立了风力机齿轮箱布局的多目标可靠性优化设计模型,分析比较了3种常见传动方案对风力机齿轮箱布局的影响,以某型号1.5 MW风力机齿轮箱为例进行了优化分析。研究结果表明,采用该设计方法得到的齿轮箱箱体体积和齿轮体积加权和值比以齿轮体积为目标的单目标设计方法更低。同时,分析结果表明,提高输入转速可大大降低齿轮箱成本。     

2K-H型人字齿周转轮系的免组装设计与成型

为了解决人字齿周转轮系加工、装配的难题,提出利用3D打印技术制造免组装人字齿周转轮系的新工艺。通过理论推导,建立变位系数、齿侧间隙与齿轮基本参数之间的关系。利用建立的关系式,对行星轮进行负变位,设计具有微量齿侧间隙的2K-H型人字齿周转轮系。利用熔融沉积成型实验平台使设计的人字齿周转轮系成型,成型后的人字齿周转轮系齿轮啮合传动正常,设计、制作相应辅件,将其装配成减速步进电机。结果表明,通过合适的间隙设计,可以利用3D打印技术实现人字齿周转轮系的免组装制造,为小尺寸、一体式人字齿周转轮系个性化定制提供了一种具有工业应用前景的全新解决方案。     

行星轮系的可靠性优化设计

介绍对2K-H（NGW）行星轮系的优化设计方法，给出了其数学模型建立方法和计算程序，根据具体设计条件，利用该计算程序可以得出满足可靠性要求的优化设计方案。     

Study of a spur gear dynamic behavior in transient regime

In this paper the dynamic behavior of a single stage spur gear reducer in transient regime is studied. Dynamic response of the single stage spur gear reducer is investigated at different rotating velocities.First, gear excitation is induced by the motor torque and load variation in addition to the fluctuation of meshing stiffness due to the variation of input rotational speed. Then, the dynamic response is computed using the Newmark method. After that, a parameter study is made on spur gear powered in the first place by an electric motor and in the second place by four strokes four cylinders diesel engine. Dynamic responses come to confirm a significant influence of the transient regime on the dynamic behavior of a gear set, particularly in the case of engine acyclism condition.     

差动轮系变速机构的设计

分析了差动轮系变速机构四种输出转速之间存在的关系,并举例说明了这种变速机构的设计步骤和计算方法。     

大功率风电机组传动系统液力变矩器的设计研究

利用几何相似设计理论,根据风电机组传动系统要求,应用MATLAB编写计算程序,求出专用导叶可调液力变矩器循环圆各部分几何尺寸并设计其机械结构.建立液力变矩器的动态数学模型,并进行MATLAB/Simulink仿真分析,验证了液力变矩器应用在风电机组传动系统的合理性,为大功率风电机组传动系统设计提供必要的理论基础.     

基于逆向工程的风力机叶片动态特性分析

综合逆向工程软件imageware,三维造型软件UG和有限元软件ANSYS,建立了750kw风力机旋转风轮的实体模型和有限元模型,对其振动模态做了仿真分析,得到振动模态数值分析结果,对叶片的动态特性进行了分析和比对,为叶片的进一步研究提供了可靠的基础。     

复杂轮系的运动分析

采用功能示意图和图论知识对复杂周转轮系进行描述。通过拓扑图中基本回路建立基本回路方程,对轮系进行运动分析。此方法能自动分析任意复杂轮系,有效解决了由于结构复杂使运动分析困难的难题,并容易在计算机实现。     

基于ANSYS的1.5MW风电机组斜齿轮轴的有限元分析

以风电机组齿轮箱的斜齿轮轴为对象,首先将Pro/E实体模型导入ANSYS建立有限元模型,在此基础上,对斜齿轮轴进行线性静力分析,最后得出形变和应力分布结果。并以此为据判断强度和刚度条件,提出轴的改进方案,提高了设计的可靠性。     

差动轮系在扩大无级变速范围中的应用

当给差动轮系的太阳轮Z3与行星架H输入适当的转速,且另一个太阳轮Z1静止时,增大或减小太阳轮Z3的转速,可使太阳轮Z1旋转并改变旋转方向。改变无级变速器的输出转速,即可使差动轮系输出较大的无级变速比。     

Torque loss in a gearbox lubricated with wind turbine gear oils

In this study, four different fully formulated ISO VG 320 wind turbine gear oils were select: a mineral oil‐based, a polyalphaolefin‐based, an ester‐based and a polyalkyleneglycol‐based fluids. Their physical properties (viscosity, thermoviscosity, piezoviscosity etc.) were characterised for a wide range of operating temperatures. A two‐stage multiplying gearbox, with helical gears, was selected to evaluate the influence of the wind turbine gear oil formulation on torque loss with the gearbox operating at low speed (130–230 rpm) and high torque (500–1000 Nm). The results obtained showed that each wind turbine gear oil formulation generated very different torque losses, evacuated heat flows and operating temperatures, with differences above 20 °C under the most severe operating conditions. A numerical model was developed, simulating all power loss mechanisms inside the gearbox, in particular the churning and friction losses. The coefficients of friction, between gear teeth and between rolling elements and bearing raceways, were calculated for all the tested oils. Copyright © 2013 John Wiley & Sons, Ltd.     

新型变速风力发电传动系统的研究

介绍一种新的基于液力机械的风力发电传动系统.该传动系统可以使风轮运转在最佳尖速比下,使风轮最大限度地利用风能,不仅可以减轻机电传动系统的极限载荷,延长使用寿命,而且还有储能作用,可以减轻因风速的瞬时变化引起的能量冲击.通过控制传动系统的液力变矩器的运转速度,来实现整个系统的变速恒频,发电机可以直接连到电网上.     

基于直廓内齿轮的行星轮系传动误差分析

直廓内齿轮代替渐开线内齿轮在加工精度、加工效率和加工成本上都有独特的优势,并且已在试验中得以证明.由于直廓内齿轮的行星轮系是多对齿轮副啮合,既有太阳轮与行星轮的渐开线齿轮副,又有行星轮与内齿轮的非渐开线齿轮副.因此,轮齿接触分析(Tooth Contact Analysis,TCA)中必然存在传动误差(Transmission Error,TE).文中通过建立系统中产生传动误差的齿轮副啮合模型,给出基于直廓内齿轮行星轮系传动误差的求解方法.最后,在多体动力学仿真软件Recurdyn中建立了行星轮系的刚柔耦合动力学模型,进行轮齿承载接触分析(Loaded Tooth Contact Analysis,LTCA).     

Blade number effect for a ducted wind turbine

Ducted wind turbine with multiple blades installed was believed to have a good wind power energy conversion effect. However, little information was available on how to design a good ducted wind turbine. In this paper the effects of blade number on a ducted wind turbine performance is studied. Numerical studies using CFD method to simulate the wind turbine performance were adopted. The duct is a converging-diverging nozzle with the turbine blades located at the throat. A rated output of a 1-kW turbine is adopted as the baseline design. It was found that the blade geometry, stagger angle, and number of blades have different duct blockage effects, and do affect the turbine performance (specifically the power coefficient and torque coefficient, etc.). The fewer number of blades has higher through flow speed, while the larger number of blades provides larger torque. The best power coefficient lies in between the two extremes. The appropriate number of blades is important to match the generator performance curve for optimal overall performance and efficiency. This paper was presented at the 9^th Asian International Conference on Fluid Machinery (AICFM9), Jeju Korea, October 16–19, 2007.     

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。