应用传递函数的零、极点辨识集聚质量系统的模态矩阵  

Identifying Modal Matrix of a Lumped Parameter Vibration System by Pole-zero Points of Transfer Function

作　　者：张治中[1] 许玉武[1] 

机构地区：[1]西北纺织工学院机械系

出　　处：《西北纺织工学院学报》1989年第3期27-36,共10页Journal of Northwest Institute of Textile Science and Technology

摘　　要：本文主要讨论集聚质量系统的刚度矩阵为对称三角降时,利用Tacohi矩阵逆问题解的唯一性来辨识系统的模态矩阵;并引证了解析函数一次极点λ=λ;留数的方根,就是Jacobi矩阵模志阵的第一行元素。因此,辨识过程中只需要输入系统的零、极点(共振和反共振频率),就可以解出模态矩阵;既不要求精确测量其峰值和相位,也不需要采用矢量图来分离总响应中其它模态的影响。辨识的精度取决于共振和反共振频率的测量精度;实验证明:它将高于振型的测量精度。A methed is proposed for this paper which applies unique solution of the inversive problem for Jacobi matrix to recognize the modal matrix, in case of stiffness matrix of a lumped parameter system is a tridiagonal matrix. The square root of residue at resonant frequency λ=λ_i is cited to the first row of mode shape matrix, and a group of pole-zero points is regared as the input datas. It follows that the peak amplitude and the phase need not be measured accursedly, and the vector diagram might not be used to separate resonance in resonant mode from the total measured resonance. It depands on the accuracy of pole-zero points, and the identifiable accuracy is more higher than the mode shape measurement.

关 键 词：传递函数 模态矩阵 反共振频率 集聚质量系统 

分 类 号：O32[理学—一般力学与力学基础] TH113.1[理学—力学]