【作者】 尚振国；

【导师】 王德伦；

【作者基本信息】 大连理工大学 ， 机械设计及理论， 2010， 博士

【摘要】 本论文在国家高技术研究发展计划项目(863计划)(No.2006AA04Z101)的资助下,结合实际工程项目背景,对大功率风力发电机增速器齿轮修形技术理论与方法进行了深入研究。首先建立斜齿轮修形的数学模型。根据齿廓修形参数和齿向修形参数的几何定义,在啮合平面上建立修形曲面方程的统一表达式；以渐开线发生线滚动角和轴向截面的旋转角为参数,建立修形齿面切极坐标方程；根据连续相切接触条件,建立修形齿面啮合方程。为后续的几何模型和有限元分析模型奠定理论基础。其次,给出计算齿轮箱整体变形的具体方法。应用有限元刚体耦合技术构造箱体柔度矩阵,计算箱体变形；根据赫兹接触理论,计算滚动轴承变形。提出了基于SQL Server数据库的斜齿轮有限元信息结构模型,开发了参数化轮齿接触分析有限元建模程序。该程序首先应用APDL生成原始直齿轮模型,将单元、节点信息导入SQL Server数据库,然后在SQL Server数据库中批量化变换、修改节点坐标,并导入ANSYS依据原单元与节点关系重建有限元网格,实现斜齿轮微观几何拓扑修形有限元分析的精确、高效建模。提出了一种基于分级剖分的网格细化方法,解决轮齿接触区网格细化难题,与以往的全齿面细化相比,可以有效地缩减节点规模,提高计算效率和精度。然后,将轮齿齿面离散成若干点,以离散点对的接触代替实际齿面接触,根据轮齿啮合变形协调条件和力平衡关系,建立轮齿面-面接触分析数字化模型。以修形参数作为设计变量,以避免啮入、啮出冲击和载荷均布为目标函数,结合面-面接触分析模型,建立考虑增速器整体变形条件的齿轮修形优化设计模型。将齿轮箱体、轴承、轴、齿轮体的受载变形耦合至齿面各接触点上,对接触点的法向变形进行三次样条拟合,从而得到齿面变形函数,再基于“反变形”思想对齿面进行修形,分析修形后的接触应力、载荷分布、接触斑点等啮合性质,从而确定修形参数。最后,通过分析考察修形参数对某风力发电机增速器输出级斜齿轮传动啮合性质的影响,确定最佳修形参数。在某企业1.5MW风力发电机增速器试验台上,采用DP1500振动信号采集分析系统,测试4种工况下增速器的振动信号。测试结果显示在计算工况下,啮合频率上的振动信号幅值最小,表明根据本文方法确定的齿轮修形参数是基本合理的,验证了本文理论和方法的正确性和有效性。更多还原

【Abstract】 A new methodology for gear modification of high-power speed increasing gearboxes for wind turbine is presented. This research is supported by the National High Technology Research and Development Program of China (863 program) under Grant No. 2006AA04Z101.Firstly, the mathematics model of modified helical gear is established. The unified expression of the modification surface equation on action plane is built according to the geometric definition of modification parameters, the tangent-polar coordinate equation of gear tooth is put forward with involute generation line roll angle and cross-section twist angle as surface parameters and the meshing equation of modified tooth flank is built based on the continuous tangent contact condition. These mentioned above are the theory foundation of the following geometric model and finite element model of modificated gears.Secondly, the flexibility matrix of gearbox is generated by advantage of finite element rigid coupling method in order to calculate the deformation of gearbox housing and the deformation of rolling bearings is calculated by Hertz law. The information structure model of helical gear finite element analysis based on SQL Server data base is put forward. The parameterized modeling program for tooth contact finite element analysis is developed. The original spur gear finite element model is established by APDL, then, node and element is input in to SQL Server data base. The rotation transformation of node coordinates is made and the elements are built according to the correlation of original node and element in order to create quickly helical gear finite element model. A hierarchical subdivision algorithm is developed for mesh refinement of tooth contact zone instead of entire tooth flank. So, the number of nodes is reduced significantly. Accordingly, computation efficiency and computation precision is increased.Then, the tooth flank is discreted to a set of points which are called reference points, and the tooth contact is replaced by the contact of these point pairs on the gears. The digitized surface to surface contact analysis model is established based on the deformation compatibility condition of teeth meshing and force equilibrium relationship. The optimum design model is put forward based on the considerations in the whole deformation of gearbox. In which, the modification parameters are regarded as design variables and Avoiding dynamic impact and geometric interference at both mesh-in position and mesh-out position as well as axial uniformly distributed load is regarded as goal function. The deformation including gearbox housing, rolling bearing, shaft and gear body is maped to the contact points on tooth flanks and the normal deformation of the contact points is fited by cubic spline. The gear is modified based on the thought of reverse deformation to determine the modification parameters by analyzing the tooth contact zone and von Mises stress etc.Finally, an example of a Speed Increasing Gearboxes for Wind Turbines is presented to demonstrate the influences of the gear’s modification parameters on meshing characteristics so as to determine the optimum modification parameters. Furthermore, the speed Increasing Gearbox’s vibration signal under four work conditions is measured by DP1500 type vibration signal collector at a 1.5MW gear test rig. It is demonstrated that the amplitude of vibration under design work condition at gear meshing frequency is minimum. It proves that the modification parameters determined is correct and the theory and method proposed is available.更多还原