利用ARV模型识别水轮机轴系模态参数

针对一类输入激振力不可测的工程结构,论述了基于向量自回归（ＡＲＶ）时间序列模型的结构模态参数识别的基本原理。为考察ＡＲ系数估计的精度,利用中心要限定量建立了估计的自回归系数矩阵协方差的表达式。分别和用水轮机的随机响应信号和自由响应信号识别了模态参数。数值仿真结果表明本文给出的识别方法是鲁棒的。此外,给出了试验结果。

IDENTIFICATION OF MODAL PARAMETERS FOR THE SHAFT SYSTEM OF HYDRAULIC TURBINE USING ARV MODEL

The basic principles for identifying of the modal parameters are described based on vector auto-regressive the series model, which deal with structures whose applied input force is not availabel. In order to examine the precision of estimated auto-regres sive coefficients, the covariance expression of the estimated auto-regressive coeffcients is established using cental limit theorem. Modal parameters are extracted from random response and be response signals of hydraulic turbine, respectiely. Numerical simulation results shaw that the method given in this paper is "ha. The test results are the given.