实验研究随机支撑刚度参数对转子系统动力学性能的影响

发布时间：2018-03-04 23:05

本文选题：随机支撑刚度　切入点：电磁支撑　出处：《河南工业大学》2011年硕士论文　论文类型：学位论文

【摘要】：支撑刚度参数是转子系统的重要动力学参数，对系统的动力学性能具有重要的影响。在实际的工程中，由于制造、安装、运行、维护等多种因素的影响，转子系统的刚度模型往往具有随机性，用随机参数模型来描述更能反映实际情况。研究随机支撑刚度参数对转子系统动力学性能影响的理论成果很多，但由于实验研究随机支撑刚度动力学问题需要加工大量的试件，这在研究时间和成本上都是不允许的，因此相关的研究很少。本文设计、加工了一种低成本的随机支撑刚度参数模拟试验平台，实验研究了随机支撑刚度参数对转子系统动力学性能的影响。主要研究内容和研究成果如下： 1.以LabVIEW为开发平台，设计开发了基于虚拟仪器技术的振动信号测试与分析系统，用于测量转子系统的振动信号。 2.基于电磁支撑的工作原理，以实验室现有的转子实验台为研究对象，设计、加工了电磁支撑，构建了电磁支撑-转子-轴承系统，用于在实验室条件下模拟转子系统的随机支撑刚度参数；以该系统为研究对象，分析了电磁支撑不通电时，影响系统动力学性能的各种不确定参数，给出了逐步识别这些不确定参数的实验方法，识别出了这些不确定参数，，建立了电磁支撑-转子-轴承系统的实验研究模型，为实验研究随机支撑刚度转子系统固有频率消除了干扰因素。 3.以电磁支撑-转子-轴承系统为研究对象，实测了电磁支撑通入0~200mA励磁电流时转子系统的固有频率，识别出了电磁支撑在不同励磁电流工况下的实际刚度参数，找出了电磁支撑的线性工作区。由于在线性工作区内支撑刚度参数与励磁电流呈线性关系，通过控制电磁支撑励磁电流的随机分布特征，可以实现各种支撑刚度参数的随机模拟。 4.以电磁支撑-转子-轴承系统为实验平台，给出了一种模拟随机支撑刚度参数的实验方法，实验研究了随机支撑刚度参数符合正态分布时转子系统固有频率的均值、方差和随机分布，通过实验值、摄动值及Monte Carlo模拟结果的对比，证明了该方法可以实现转子系统支撑刚度的随机模拟，且实验结果可信，降低了实验成本，提高了经济效益。该实验平台可用于后续转子系统随机动力学响应问题的研究。
[Abstract]:The support stiffness parameter is an important dynamic parameter of the rotor system, which has an important influence on the dynamic performance of the rotor system. In actual engineering, it is affected by many factors, such as manufacture, installation, operation, maintenance and so on. The stiffness model of rotor system is always stochastic, and the stochastic parameter model can better reflect the actual situation. There are a lot of theoretical results to study the influence of the random support stiffness parameters on the dynamic performance of the rotor system. However, due to the large number of specimens that need to be processed to study the dynamics of random braced stiffness experimentally, this is not allowed in terms of research time and cost, so there are few related studies. A low cost simulation platform of random bracing stiffness parameters is developed, and the effect of random bracing stiffness parameters on the dynamic performance of rotor system is studied experimentally. The main contents and results are as follows:. 1. The vibration signal testing and analysis system based on virtual instrument technology is designed and developed on the platform of LabVIEW, which is used to measure the vibration signal of rotor system. 2. Based on the working principle of electromagnetic support and taking the existing laboratory rotor test bench as the research object, the electromagnetic support is designed and machined, and the electromagnetic brace-rotor bearing system is constructed. It is used to simulate the random support stiffness parameters of the rotor system under the laboratory condition, taking the system as the research object, the various uncertain parameters which affect the dynamic performance of the system are analyzed when the electromagnetic support is not electrified. The experimental method of identifying these uncertain parameters step by step is given, and the experimental research model of electromagnetic brace-rotor bearing system is established. The interference factors are eliminated for the experimental study of the natural frequency of the rotor system with random support stiffness. 3. Taking electromagnetic brace-rotor bearing system as the research object, the natural frequency of the rotor system is measured when the electromagnetic support passes through the excitation current of 0 ~ 200mA, and the actual stiffness parameters of the electromagnetic support under different excitation current conditions are identified. The linear working area of electromagnetic bracing is found. Because of the linear relationship between the support stiffness parameters and the excitation current in the linear working area, the random distribution characteristics of the electromagnetic braced excitation current are controlled. The random simulation of various support stiffness parameters can be realized. 4. Taking the electromagnetic brace-rotor bearing system as the experimental platform, an experimental method to simulate the random bracing stiffness parameters is presented. The experimental results show that the random bracing stiffness parameters accord with the mean of the natural frequency of the normal distribution time-transfer subsystem. The variance and random distribution are compared with the experimental values, perturbation values and Monte Carlo simulation results. It is proved that this method can realize the stochastic simulation of the support stiffness of the rotor system, and the experimental results are credible and the experimental cost is reduced. The experimental platform can be used to study the stochastic dynamic response of the subsequent rotor system.
【学位授予单位】：河南工业大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH113

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