基于时域响应有限元模型修正的磁轴承—转子系统参数识别

发布时间：2018-06-08 16:27

本文选题：磁轴承 + 瞬态时域响应　；参考：《南京航空航天大学》2012年硕士论文

【摘要】：磁轴承-转子系统的动态特性是磁轴承的支承参数与转子动力学综合作用的结果。本文从磁轴承-转子系统的时域响应出发，采用有限元模型修正技术，围绕磁轴承支承动态特性的参数识别问题展开。具体研究内容如下：利用有限元方法建立轴承-转子系统有限元动力学模型，结合通用有限元软件NASTRAN介绍了系统瞬态时域响应以及转子不平衡响应的求解方法，并通过实例验证其求解可靠性。以基于模态参数的有限元模型修正为基础，，实现了基于时域响应的有限元模型修正技术，对其中的关键技术进行理论研究，最终实现修正过程。通过仿真算例验证了时域修正方法的精度。为了建立模型修正所需要的精确有限元模型，对磁轴承-转子系统的阻尼进行了研究。应用时域修正方法通过试验数据修正了自由-自由状态转子的模态阻尼比以及静态悬浮下的磁轴承-转子系统的支承参数，最后识别出磁轴承-转子系统的静态悬浮支承刚度和阻尼。从控制特性出发研究了磁轴承支承参数的理论非线性。结合支承刚度的理论非线性模型，建立了非线性支承参数下的磁轴承-转子系统有限元模型。通过有限元分析研究了非线性支承参数对系统动态响应的影响，并应用时域修正技术识别了磁轴承的非线性参数。
[Abstract]:The dynamic characteristics of the magnetic bearing-rotor system are the result of the combined action of the supporting parameters of the magnetic bearing and the rotor dynamics. Based on the time-domain response of the magnetic bearing-rotor system, the finite element model correction technique is used to solve the problem of parameter identification of the dynamic characteristics of the magnetic bearing. The specific research contents are as follows: the finite element dynamic model of bearing-rotor system is established by finite element method, and the transient time-domain response and rotor unbalance response of the system are introduced with the general finite element software NASTRAN. Based on the finite element model modification based on modal parameters, the finite element model correction technology based on time domain response is realized. The key technologies are theoretically studied and the correction process is finally realized. The accuracy of the time domain correction method is verified by a simulation example, and the damping of the magnetic bearing-rotor system is studied in order to establish the accurate finite element model for the model modification. The time domain correction method is used to modify the modal damping ratio of the free state rotor and the supporting parameters of the magnetic bearing rotor system under static suspension. Finally, the static suspension stiffness and damping of the magnetic bearing-rotor system are identified, and the theoretical nonlinearity of the supporting parameters of the magnetic bearing is studied based on the control characteristics. A finite element model of magnetic bearing-rotor system with nonlinear bearing parameters is established based on the theoretical nonlinear model of supporting stiffness. The influence of the nonlinear bearing parameters on the dynamic response of the system is studied by finite element analysis, and the nonlinear parameters of the magnetic bearing are identified by using the time-domain correction technique.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH133.3

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