一种不受相位噪声影响的模态参数识别法

本文提出了一种根据幅值频响数据来识别模态参数的频域识别法.该方法首先通过识别幅值频响函数模型来得到传递函数的零点和极点.鉴于不同结构系统可以有完全相同的幅值频响函数,文中提出了由相位频响数据来判定传递函数零点的号性,以唯一确定传递函数,从而消除了相位噪声对模态参数识别结果的影响.作为例子,文中给出了计算机模拟实验例子和滚动轴承支承动态参数识别的应用实例.

A METHOD FOR THE IDENTIFICATION OF MODAL PARAMETERS UNAFFECTED BY PHASE NOISE

An estimation algorithm that utilizes amplitude frequency response measurements to identify modal parameters is presented in this paper. The algorithm uses a curve-fitting method to identify the modal of amplitude frequency response functions, and then transforms its 'poles' and 'zeros' to those of transfer function's. Phase information is used to determine the sign of 'zeros', which, no doubt, leads to the low requirement for phase measurements. An ezample of the identification from simulated experimental results is discussed to illustrate the performance of the algorithm in assessing the modal parameters in noise data case. Discussion is also given to its application in the experimental study of dynamic characteristics of taper roller bearings.