基于层次分析法的涡旋压缩机振动特性研究

发布时间：2018-06-06 04:25

本文选题：涡旋压缩机 + 振动　；参考：《中国矿业大学》2017年硕士论文

【摘要】：随着涡旋压缩机的普及,其关注度越来越高。涡旋压缩机运转的平稳与否直接关系到其性能的好坏,而振动信号就是其工作性能的语言。想要获得目标参数,就需要利用相应的方法分析涡旋压缩机的振动信号。由于涡旋压缩机的独特结构,其壳体振动情况复杂,然而在关于涡旋压缩机振动信号的文献中,缺少对压缩机壳体表面振动位置的特殊性的系统研究。此外,由于涡旋压缩机课题研究时间较短,缺少对其进行实时监测的方法,无法判断在其运行过程中的性能变化。本课题基于涡旋压缩机的特殊构造,提出了四个振动特殊位置作为研究对象,即排气口壁面、动涡旋盘及十字滑环位置、曲轴的主轴承以及副轴承对应壳体位置,并对其进行了力与力矩平衡分析,得到不同位置振动产生的原因。并建立涡旋压缩机振动测试系统,获取特殊位置振动信号并进行中值滤波处理,最大限度的排除信号间的干涉与干扰,利用时域中的均方根值和方差两个特征值分析振动波动情况,得到动涡旋盘与十字滑环与壳体的连接位置产生的振动程度最大且波动最剧烈。随后,本文首次提出振动贡献值的概念,此值是利用层次分析法进行求得。在利用层次分析法过程中,提出一种符合涡旋压缩机工况的判断矩阵,即综合信号功率谱和偏向干函数两者建立,以减少计算误差。最终得到特殊位置为涡旋压缩机整体振动提供的贡献比值,得到排气口壁面处的振动对涡旋压缩机整体振动产生的贡献比值最大,即对整体振动影响最大,提出涡旋压缩机轴向振动在减振研究中不可忽视。根据贡献比值可以对涡旋压缩机运转工况进行实时监测,当贡献比值出现波动变化较大的情况时反应出相应的位置可能出现故障,并根据特殊位置的力及力矩分析情况判断出可能产生故障的较大因素,该方法可以作为涡旋压缩机故障诊断的理论依据。基于本文提出的整套计算理论,采用MATLAB软件进行编程,并且把此程序利用到本次实验系统中进行应用。在实验过程中,该程序可以直接显示出不同测试位置的振动时域信号及特征值变化,以及不同位置信号之间的功率谱、相干函数以及偏相干函数等图谱,最重要的功能是可以直接显示出不同位置为涡旋压缩机振动提供的贡献比值,达到对涡旋压缩机运作过程中实时监测的目的。
[Abstract]:With the popularization of scroll compressor, its attention is more and more high. The smooth operation of scroll compressor is directly related to its performance, and the vibration signal is the language of its working performance. In order to obtain the target parameters, it is necessary to analyze the vibration signal of the scroll compressor by using the corresponding method. Because of the unique structure of the scroll compressor, the vibration of the shell is complicated. However, in the literature about the vibration signal of the scroll compressor, there is a lack of systematic research on the particularity of the vibration position of the shell surface of the compressor. In addition, due to the short research time of the scroll compressor, it is impossible to judge the performance change in the running process because of the lack of real-time monitoring method. Based on the special structure of the scroll compressor, four special vibration positions are put forward, namely, the wall of the exhaust port, the position of the moving scroll disk and the cross slide ring, the position of the main bearing of the crankshaft and the corresponding shell position of the secondary bearing. The force and torque balance are analyzed and the causes of vibration at different positions are obtained. The vibration test system of scroll compressor is established to obtain vibration signal of special position and process median filter to eliminate interference and interference of signal as much as possible. Two eigenvalues of root mean square and variance in time domain are used to analyze the vibration fluctuation. It is obtained that the vibration caused by the connection position between the moving scroll disk and the cross slide ring and the shell is the largest and the most violent. Subsequently, the concept of vibration contribution value is proposed for the first time, which is obtained by analytic hierarchy process (AHP). In the process of using analytic hierarchy process, a judgment matrix which accords with the working condition of scroll compressor is put forward, that is, the comprehensive signal power spectrum and the deviation dry function are established to reduce the calculation error. Finally, the contribution ratio of the special position for the whole vibration of the scroll compressor is obtained, and the contribution ratio of the vibration at the exhaust port wall to the whole vibration of the scroll compressor is obtained, that is, the effect on the whole vibration is the greatest. The axial vibration of scroll compressor can not be ignored in the study of vibration reduction. According to the contribution ratio, the working condition of scroll compressor can be monitored in real time. When the contribution ratio fluctuates greatly, the corresponding position may be malfunction. According to the analysis of the force and torque of special position, the large factors which may produce the fault are judged. This method can be used as the theoretical basis for the fault diagnosis of the scroll compressor. Based on the whole calculation theory presented in this paper, MATLAB software is used to program, and the program is applied to this experiment system. In the process of experiment, the program can directly display the vibration time domain signals and eigenvalues of different test positions, as well as the spectrum of power spectrum, coherence function and partial coherence function between different position signals. The most important function is to directly display the contribution ratio of different positions to the vibration of the scroll compressor, so as to achieve the purpose of real-time monitoring the scroll compressor during its operation.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH45

【参考文献】