[航空航天]机车振动论文：机车车辆多点激励模态试验系统研究.doc

机车振动论文：机车车辆多点激励模态试验系统研究【中文摘要】随着机车车辆运营速度的提高,车辆振动强度也随之增强,影响了结构的疲劳寿命。研究结构振动特性,可以优化车辆结构,抑制过大振动,改善车辆性能,具有重要意义。而模态试验是获得结构振动特性的主要手段之一,其中多点协调激励模态试验能够在提高模态纯度的同时准确识别铁道车辆模态参数。本文以车辆为研究对象,研制了多点协调激励系统,并进行结构动态特性参数测试。第二章阐述了多点协调激励模态试验技术原理；探讨了多点协调激励在二系悬挂车辆上进行模态试验的适用性,同时建立具有二系悬挂车辆的纯模态判据和模态纯度指示函数；应用多点协调激励模态技术,对某二系悬挂车辆进行了仿真。第三章以二系悬挂模型车为对象,以多点协调激励理论为基础,Labview为编写平台,研制了多输入多输出纯模态试验系统。系统采用网格法对调力区间进行了优化设计；利用模态纯度指标为目标函数实现了系统的反馈控制。最后,应用研制的模态试验系统对二系悬挂模型车进行了多点协调激励模态试验,得到了模型车各阶固有频率及振型。对比使用Ploymax参数识别方法获得的该模型车的固有频率和振型,表明在误差范围内两次试验的结果是一致的,而多点协调激励法获得的各阶模态纯度更高。【英文摘要】With the increasing velocity of locomotive train, the train vibration also has increased, thus the structure fatigue life is influenced. It is meaningful to study the vibration characteristics of structure, through which we can optimize the structure of vehicles, restrain the overlarge vibration and improve the performance of vehicles. Modal test is one of the major means to obtain structural vibration characteristics. Multi-point coordinated excitation modal test can accurately identify the modal parameters of railway vehicles and improve the modal purity at the same time. Taking the vehicle as the object of study, this paper developed a multi-point coordinated excitation system, and made the structural dynamic characteristics parameter testing.Chapter two introduced the principle of the multi-point coordinated excitation modal test technology, the applicability of multi-point coordinated excitation modal test on secondary suspension vehicles, and established the pure modal criterion and modal purity indicating functions of secondary suspension vehicles at the same time, then conducted the simulation on secondary suspension vehicle by applying the multi-point coordinated excitation modal technique.In chapter three, taking the secondary suspension model car as the object, taking the multi-point coordinated excitation theory as the basis and the Labview as the compiling platform, a multi-input and multi-output pure modal test system was developed. The system made an optimization design on the adjustable force interval of force signal via grid method; the feedback control of the system was achieved by using purity as the target function.At last, with the developed modal test system, multi-point coordinated excitation modal test was conducted on the secondary suspension model car, and the natural frequency and vibration mode of the model car was obtained. Comparing the result with the natural frequencies and vibration modes obtained via Ploymax parameter identification method, it indicated that the results of the two tests are in accordance with each other within an acceptable error, but the multi-point coordinated excitation method got a higher modal purity of each vibration mode.【关键词】机车振动 模态分析 模态纯度 多点协调激励 铁道车辆【英文关键词】locomotive vibration modal analysis mode purity multi-point coordinated excitation railway vehicle【目录】机车车辆多点激励模态试验系统研究摘要6-7ABSTRACT7第1章 绪论11-161.1 研究背景11-121.2 国内外现状分析12-151.3 研究思路及内容15-16第2章 多点协调激励模态试验理论16-312.1 模态分析的基本理论16-182.2 多点协调激励模态试验基本理论18-252.2.1 MIMO频响函数估计18-192.2.2 参数估计19-202.2.3 车辆达到纯模态依据20-242.2.4 纯度指示函数24-252.3 具有二系悬挂系统车辆实现纯模态计算分析25-282.3.1 具有二系悬挂系统车辆频响函数25-262.3.2 具有二系悬挂系统车辆纯模态参数的获取26-282.4 试验中的非线性和误差28-302.5 本章小结30-31第3章 多点协调激励模态试验系统设计31-453.1 试验系统设计概述31-323.2 多点协调激励系统硬件组成32-333.2.1 信号调理模块32-333.2.2 数据采集模块333.3 多点协调激励模态系统软件设计33-413.3.1 设计软件的流程图34-353.3.2 软件主要模块及其用途35-413.4 调力控制41-443.5 本章小结44-45第4章 悬挂系统多点激励模态试验及结果分析45-624.1 试验系统构成45-514.1.1 试验对象45-464.1.2 激振器/传感器配置46-484.1.3 选择激励谱48-494.1.4 试验的原理494.1.5 多点协调激励模态试验的流程49-504.1.6 模型车试验准备50-514.2 模型车2点协调激励模态试验51