基于双弹性支撑的复合式行星齿轮传动系统故障机理及其诊断方法研究

By combining the advantages of planetary gear and ordinary gear, multistage compound gearbox has been widely applied to large and complex machinery transmission system. In some situations, mechanical power transmission system may have special double-elastic characteristics for its elastic foundation and elastic support, which cause a natural phenomenon of axial misalignment in the output shaft of gearbox when working. Due to the complex transmission structure, special installation condition and poor working conditions, the vibration signals of the normal gearbox are mixed with serious modulation sidebands and gear mesh frequency and its high-order. When a fault occurs, the impact modulation caused by fault couples with the smooth modulation. For above special characteristic, the technology for traditional gearbox fault diagnosis fail to solve the difficulty of fault feature extraction in multistage compound gearbox based on double-elastic support.By finite element method(FEM) and lumped parameter method(LPM), the dynamics models of multistage compound gearbox based on the double-elastic support are established. The mechanism of fault generation and dynamic evolution in gearbox is analyzed deeply by combining the kinetic analysis and systemic experimental research. A mathematics coupling model, which contain impact modulation and smooth modulation, is established. In order to separate the impact modulation and smooth modulation and extract the characteristic frequencies of gearbox fault, a new signal separation method based on sparse decomposition is proposed. Moreover, to improve the extraction accuracy of fault characteristic frequency, discrete spectrum correction technology and order tracking analysis based on mesh frequency are utilized at the same time. The above researches will provide a new and targeted fault diagnosis method for multistage compound gearbox.

行星轮系+定轴轮系的多级复合式齿轮箱兼备两种传动方式的优点，被广泛应用到大型复杂机械设备的传动系统。在某些场合，机械传动系统的安装条件具有特殊的弹性基础和弹性支撑的双弹性特点，导致齿轮箱运行时输出轴天然地存在轴不对中现象。复杂的传动结构、特殊的安装条件以及恶劣的工作环境使得正常齿轮箱的振动响应存在严重的调制边频带和齿轮高阶啮合频率。当有故障时，平稳调制和冲击调制相互耦合。传统的齿轮箱故障诊断技术难解双弹性支撑多级复合式齿轮箱故障特征提取的难点。本项目拟采用有限元法和集中参数法建立双弹性支撑的多级复合式齿轮箱动力学模型，结合动力学分析和系统性的实验研究，深入分析故障产生及动态演化的机理；建立平稳与冲击耦合调制信号的数学模型，研究基于稀疏分解的耦合调制分离技术，提取故障特征；融合离散频谱校正技术和基于啮合频率的阶比跟踪分析方法，提高特征频率定位精度，构成一种全新的多级复合式齿轮箱故障诊断方法。

利用现象学模型、动力学建模方法和集中参数法建立了定轴和行星轮系齿轮箱模型，从理论上研究了定轴齿轮在正常、平稳型故障和冲击型故障时的振动调幅信号产生机理，总结了频谱特征。根据行星轮系的运动特点，考虑时变传递路径函数和时变啮合力方向的影响，研究了轮系在正常情况下振动调制边带的产生机理，并验证了路径传递函数在不同频率成分下不同，但都能表示为以行星架转频为基频的傅里叶级数。研究了当行星轮系齿轮出现平稳型和冲击型故障时振动信号的频谱特征。根据机理和实验研究，分别建立了定轴轮系故障状态振动信号数学模型、轴承内圈和外圈故障振动信号数学模型、行星轮系故障振动信号数学模型，这些模型是信号处理方法研究中仿真的基础，很多国内外学者引用了我们发表论文中的定轴齿轮和轴承故障的振动信号数学模型。针对齿轮系统时变工作环境，基于离散频谱校正技术，提出了一种齿轮箱振动响应阶次跟踪方法。基于稀疏分解理论和复合式齿轮箱的故障产生机理，提出了一系列有效提取齿轮故障和轴承故障中的平稳型故障和冲击型故障特征的方法。结合阶次跟踪方法和稀疏分解理论，实现齿轮系统非平稳工况下故障解耦。根据齿轮故障机理和稀疏信号分离方法，形成了一套完善的齿轮系统“机理研究-故障特征提取-诊断方法”的理论成果和工程应用技术。.共发表SCI论文9篇(其中中科院二区top 3篇，三区5篇)，EI收录论文5篇；申请授权发明专利3件，受理发明专利共5件；博士学位论文2篇(其中一篇获得2017年华南理工大学十佳优秀博士论文，一人获博士国家奖学金)，硕士学位论文7篇。在国内学术会议作分会主题邀请报告3次，一篇会议论文获2018年全国设备监测诊断与维护学术会议优秀文论奖。发表的论文总引用数量中英文258篇次，SCI总引用为95篇次。单篇SCI最高引用46篇次, 引用次数在2016年《Journal of Sound and Vibration》杂志发表的562篇论文中排名第四，在国内外学术界有较大的学术影响。