复合齿轮传动系统振动响应调制机理及稀疏分离方法研究

发布时间：2018-05-13 19:30

本文选题：齿轮传动系统 + 振动响应机理　；参考：《华南理工大学》2015年博士论文

【摘要】：当齿轮传动系统某一部件出现故障时,常常会诱发其他故障的发生和恶化,再受到信号传递路径以及其正常啮合振动的影响,不同激励源产生的振动信号相互耦合,增加了故障诊断的难度。深入研究齿轮系统各类故障振动响应的演化机理和特征提取方法,具有重要的理论研究意义和工程应用价值。建立齿轮传动系统动力学模型,揭示了齿轮啮合频率高阶特征及其调制边频带的产生机理。齿轮受载后的静弹性变形与啮合动刚度的相互作用以及系统的非线性反馈是啮合频率高阶特征产生的主要原因。平稳型故障导致的齿轮副周节位移误差激励与啮合动刚度的相互作用诱发故障齿轮转频调制啮合频率的边频带;冲击型故障激励的脉冲力序列诱发齿轮冲击故障频率调制轮系固有频率,并与啮合动刚度负反馈作用使振动响应中出现“虚假”共振峰,但所有的共振频带都是被冲击故障频率在全频带内等间隔离散化。建立了正常行星轮系振动响应耦合调制信号模型。受啮合点与固定位置传感器之间传递路径函数和啮合力在传感器坐标方向投影函数的影响,传感器采集到的振动响应表现出行星架转频调制啮合频率的等间隔边频带特征。传递路径函数和方向投影函数均是周期函数,可用傅里叶级数展开,基频为行星架的转频,展开的阶次决定了调制边频带的宽度。均布式行星轮系的振动响应只在行星轮个数的整倍数频率处存在幅值,当啮合频率及其高阶倍频是行星轮个数的整倍数时,啮合频率成分有幅值,且调制边频带对称分布;反之,啮合频率成分的幅值为零,调制边频带非对称分布。提出了一种基于啮合频率和频谱校正技术的齿轮箱振动响应阶次跟踪分析方法。该方法融合了时频分布的矩估计和峰值搜索法,但能克服矩估计不适用于多分量信号的提取和峰值搜索法在时频分辨率上的限制;通过提取啮合频率成分,再间接获得瞬时转速成分,克服了振动加速度传感器采集信号中频率较低的转频成分幅值小,难以直接提取的难点。经过能量重心法校正后,可获得高精度的齿轮箱瞬时转速估计值,显著提高阶次分析的频率和幅值估计精度。风电齿轮箱振动信号阶次跟踪仿真分析中,提取的输出轴瞬时转速估计值的最大相对误差仅为0.024%,前四阶啮合频率幅值的估计值的最大相对误差仅为2.09%。汽车变速器试验和风电复合式齿轮箱的工程应用验证了该方法的有效性和实用性。提出了一种新的齿轮箱混合故障耦合调制信号分离方法,该方法将具有明确物理意义的平稳调制字典和冲击调制字典、相关滤波法、频谱校正和优化匹配追踪有机的结合在一起,应用于齿轮和轴承故障诊断。建立的平稳调制字典和冲击调制字典融合了齿轮系统故障机理、齿轮箱的结构和运行参数、实测振动信号的特征,物理意义明确,兼具解析字典和学习字典的优点。应用比值校正法从实测振动信号中获得谐波原子参数的精确解,优化平稳调制字典,并对匹配分解系数进行幅值恢复,提高了平稳调制成分的分离精度。基于相关滤波法的冲击响应原子参数优化,能大幅度地降低冲击调制字典的冗余度;分段匹配追踪方法,降低了稀疏系数求解过程中内积计算的点数,达到提高信号稀疏分解速度的目的。通过仿真分析和试验测试验证了所提方法具备分离齿轮和轴承混合故障信号的能力。
[Abstract]:When one part of the gear transmission system fails, it often induces the occurrence and deterioration of other faults, and is influenced by the signal transmission path and its normal meshing vibration. The vibration signals produced by different excitation sources are coupled to each other, and the difficulty of the fault diagnosis is increased. The evolution machine of various fault vibration responses of the gear system is studied in depth. The method of theory and feature extraction has important theoretical research significance and engineering application value. The dynamic model of gear transmission system is set up, which reveals the high order characteristic of gear meshing frequency and the generation mechanism of the modulation edge frequency band. The interaction of the static elastic deformation with the meshing dynamic stiffness after the gear loading and the nonlinear feedback of the system are meshing. The main reason for the high order characteristic of the frequency is that the interaction between the gear pair and the meshing dynamic stiffness induced by the stationary fault induces the side frequency band of the gear frequency modulation of the fault gear, and the pulse force sequence of the shock type excitation induces the natural frequency of the gear shock fault frequency modulation wheel, and it is engaged with the meshing movement. The "false" resonance peak is found in the vibration response, but all the resonance bands are isolated and dispersed in the whole frequency band. The coupling modulation signal model of the normal planetary gear system is established. The transmission path function and the meshing force between the meshing point and the fixed position sensor are used in sensing. The vibration response of the sensor is influenced by the projection function of the coordinate direction. The vibration response of the sensor is characterized by the equal interval band of the frequency modulation of the trip star frame. The transfer path function and the direction projection function are periodic functions, which can be expanded by Fourier series, the fundamental frequency is the conversion of the planetary frame, and the order of the expansion determines the width of the band width of the modulated edge. The vibration response of the uniform planetary gear train is only amplitude at the frequency of the number of planetary gear. When the meshing frequency and its high order frequency doubling is the integer of the number of planetary gear, the meshing frequency component has the amplitude, and the modulation side frequency band is symmetrical distribution; conversely, the amplitude of the meshing frequency is zero and the modulation side frequency band is asymmetrical. A step tracking analysis method for gearbox vibration response based on meshing frequency and spectrum correction technology is used. The method combines moment estimation and peak search method of time frequency distribution, but it can overcome the moment estimation not suitable for the extraction of multicomponent signals and the limitation of the peak search method on the time frequency resolution. The instantaneous speed component is obtained indirectly, which overcomes the difficulty of the small amplitude of the frequency conversion component of the vibration acceleration sensor, which is low in the middle frequency of the acquisition signal. After the correction of the energy center of gravity, the estimation of the instantaneous speed of the gearbox can be obtained, and the frequency and amplitude estimation accuracy of the order analysis can be greatly improved. The wind power gear box is improved. In the simulation analysis of the order tracking of vibration signals, the maximum relative error of the estimated instantaneous speed of the output shaft is only 0.024%. The maximum relative error of the estimated value of the first four order meshing frequency amplitude is only the engineering application of the 2.09%. automobile transmission test and the wind electric compound gear box. The validity and practicability of the method are proved. A new hybrid fault coupled modulation signal separation method for gearbox is introduced. This method combines the stationary modulation dictionary with the impact modulation dictionary, the correlation filter method, the spectrum correction and the optimal matching tracking. It is applied to the diagnosis of gear and bearing barrier. The stationary modulation dictionary and impact modulation are established. The dictionary combines the fault mechanism of the gear system, the structure and operating parameters of the gear box, the characteristics of the measured vibration signals, the physical meaning, the advantages of both the Analytical Dictionary and the learning dictionary. The exact solution of the harmonic atomic parameters is obtained from the measured vibration signals by the ratio correction method, and the stationary modulation dictionary is optimized and the matching decomposition coefficient is added into the dictionary. The recovery of the line amplitude improves the separation precision of the stationary modulation component. The correlation filtering method based on the optimization of the impact response atomic parameters can greatly reduce the redundancy of the impact modulation dictionary. The piecewise matching tracing method reduces the number of inner product points in the sparse coefficient solving process and improves the signal sparse decomposition speed. The simulation and experimental tests show that the proposed method has the ability to separate signals from gear and bearing faults.

【学位授予单位】：华南理工大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TH132.41

【参考文献】