倒置式轴承动特性试验台建模及参数识别精度  

Modeling and parameter identification accuracy on inverted test bed of dynamic characteristic coefficients for sliding bearing

作　　者：陈润霖[1] 王建磊[1] 袁小阳[2] 刘凯[1] Chen Runlin;Wang Jianlei;Yuan Xiaoyang;Liu Kai(School of Mechanical and Precision Instrument Engineering, Xi＇an University of Technology, Xi＇an 710048, China;Key Laboratory of Education Ministry for Modem Design and Rotor-Bearing System, Xi＇an Jiaotong University, Xi＇an 710049, China)

机构地区：[1]西安理工大学机械与精密仪器工程学院,陕西西安710048 [2]西安交通大学现代设计及转子轴承系统教育部重点实验室,陕西西安710049

出　　处：《华中科技大学学报（自然科学版）》2018年第6期31-37,共7页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家重点基础研究发展计划资助项目(2015CB057303-2);陕西省教育厅科研计划资助项目(15JK1528)

摘　　要：针对滑动轴承倒置式试验台,建立了轴承转子动力学模型和动特性系数测试的频域模型,提出了基于正反动力学仿真的动特性系数识别的精度评估方法,重点分析了测试误差和激振频率对动特性系数识别精度的影响.结果表明：刚度阻尼系数的识别误差与幅值误差的大小基本成正比;相位误差对主刚度和交叉阻尼影响很小,对交叉刚度和主阻尼影响较大;当同时存在幅值和相位误差时,对动特性系数识别精度的影响为两种误差单独影响效果的叠加.当采用单频激振法测试轴承动特性时,宜在低频和共振频率附近分别进行两次测试.低频范围内主刚度和交叉阻尼识别数据较为可信,而在共振频率附近主阻尼识别误差小;交叉刚度对相位误差敏感,只有当相位误差很小时识别结果才较为可信.For sliding bearing inverted test bed,the dynamic model of test bed system and the frequency model of dynamic characteristics test were established.A accuracy evaluation method of dynamic characteristic coefficients identification was proposed based on the forward and inverse dynamics simulation.The influences of displacement measurement error and excitation frequencies on the identification accuracy were analyzed.The results show that the identification error of stiffness and damping coefficients is mainly proportional to the amplitude error.The phase error has a little effect on the principal stiffness and cross damping,and a great impact on the cross stiffness and principal damping.When the measurement of displacement has the amplitude and phase errors,the impacts of these errors on the identification accuracy of dynamic characteristic coefficients are the superimposed results of two separate errors.It is suggested that two test should be implemented in both low excitation frequency and resonant frequency when identifying the dynamic coefficients under single frequency excitation method.The principal stiffness and cross damping identified in low frequency are more plausible,and the principal damping around resonant frequency has less identification error.The cross stiffness is very sensitive to phase error,and the identification results is credible only in very small phase error.

关 键 词：滑动轴承 动特性系数 倒置式试验台 参数识别精度 激振频率 

分 类 号：TH133.31[机械工程—机械制造及自动化]