电子设备硬振设计的模态测试与分析

【作者】 张天琳；

【导师】 黄大贵；

【作者基本信息】 电子科技大学 ， 机械电子工程， 2007， 硕士

【摘要】 电子设备小型化已成发展趋势，现有的电子设备抗振性不能满足要求。由于机电系统小型化和轻量化以及其愈来愈严酷的应用环境条件，振动和冲击对机电系统的影响已变得非常突出，因此机电系统的结构的设计必须重视结构的动态特性分析。如果不能比较准确地把握电子设备本身性能，就无法形成一套完整的电子设备的抗振动设计方法，更难以主动的、有针对的提出改进和保证设备动态性能的方案。因此在实现电子设备硬装过程中，必须掌握电子设备结构的动态性能，才能有针对性地进行结构设计，实现电子设备硬装。于是，对设备进行模态分析，了解其固有频率等性质就显得非常必要。模态分析是一种研究结构动力特性的方法，是系统辩识方法在工程振动领域中的应用，是结构动态设计及设备故障诊断的重要理论基础；结构动力修改则研究系统结构做出某种修改后动力学特性的变化或为获得某种动力学特性应如何对系统进行修改等问题。本论文正是针对上述问题，对组件和整机系统进行实验模态测试与分析，总结出一套对电子设备模态测试以及分析的方法。通过研究实验数据，了解参数估计的原理及方法，从频域方面进行模态的参数辨识。从而辨识出被测对象的模态参数，并总结出结构参数对它的影响。测得的模态数据可以为有限元模型提供匹配依据，使其数值计算结果能与实验测试相匹配，这样的有限元模型可为电子设备硬装设计或改进提供有力的设计指导。在得到模态参数之后，对组件以及整机系统进行谱分析。通过响应谱分析来了解对象的振动特性。冲击谱分析检测电子设备整机或关键元器件，部件的抗震，抗冲特性。随机谱分析的主要目的是研究与正弦扫频信号相比对模态参数提取的影响等。本文提出了一些对冲击以及随机响应谱进行分析的方法。在模态分析的基础上对设备进行结构动力学修改。通过实验得到组件的动力学特性对整机的动态性能频率等方面的影响，并通过改变结构来优化设计，得到所需要的动态特性。再根据组件和整机系统在模态分析之后得到的机械性能指标，开发出有效方法来控制组件和整机振动的方法，本文主要讨论了组件阻尼器的设计以及动态设计两种方法，得到了一定的减振效果。更多还原

【Abstract】 Miniaturization has become the trend in the development of electronic equipment, so that vibration resistance of electronic equipment can not meet the existing requirements. Because the small and lightweight application of mechanical and electrical systems, and the increasingly harsh environmental conditions. Vibration and shock’s effect of the electrical and mechanical systems have become very prominent. Therefore the design of the mechanical and electrical systems must attach importance to the dynamic characteristics of the structure analysis. If we can not accurately grasp the properties of electronic equipment, it is impossible to establish a complete set of anti-vibration design methods of electronic equipment, and also having less initiative. It is necessary to improve the dynamic performance of the equipment and guarantee programs. During the install process of electronic equipment, we must master the dynamic performance of electronic equipment. So that we can be targeted to the structural design and electronic equipment install. Therefore, the modal analysis of equipment, which using to understand their nature such as natural frequencies, is very necessary.Modal analysis is a method to study the effects of structural dynamic characteristics, applying the system identification in the field of vibration engineering. Dynamic design equipment and fault diagnosis are basis for the important theoretical. Dynamic changes to the structure research that system make some changes in the revised dynamics. It is also research that how to obtain some dynamic characteristics by the system changes and other issues.This paper will address these issues. It contains experimental modal testing and analysis of components and the whole system, and summed up a set method of electronic equipment modal testing and analysis. Based on the experimental data, realize the principles and methods of parameter estimation, and understand the modal parameter estimation from frequency domain. Determine the modal parameters of the measured object, and summed up the impact of structural parameters of modal parameters. It can provide numerical results to match the finite element model. This finite element model can provide effective guidance for the design or improve electronic equipment.Understand the vibration characteristics of testing equipment by responding spectrum analysis. The impact spectral analysis is to study the anti-vibration and the impact characteristics of components or critical parts. Random spectral analysis is the main purpose of the study the influence of modal parameters compared with the sin-swept signal extraction and the random signal. This paper presents some method of the shock and random response spectrum analysis.Founded on the experimental analysis, it can know the dynamic characteristics of components and the whole system. It focuses on how the dynamic characteristics of components affect the dynamic performance of a whole system. It also study that how to optimize the structure to gain the dynamic characteristics which are required.Based on systems and components performance from the modal analysis, develop effective ways to control parts and components vibration. It main include designing internal components damper to reduce vibration and dynamic designing. And the result of the experiment show that this design obtains better reduces vibration effective.更多还原