基于子空间法与子结构法时变结构连接处的物理参数在线辨识

结构系统连接处的物理参数对于系统建模具有极其重要的影响,如何准确合理地辨识出结构系统连接处的物理参数一直是人们研究的热点,也一个存在相当大难度的问题。一般利用传统的子结构法进行参数辨识,还仅局限于针对非运动状态下系统结构连接处的物理参数识别问题。文中在传统子结构法的基础上,提出一种计算结构系统在运动状态下连接处时变物理参数在线辨识方法,这种方法分两步对系统进行辨识。首先利用子空间法实时辨识出时变结构系统的特征值与特征向量,然后利用辨识出的特征值与特征向量以子结构法为基础在线辨识出连接处的物理参数。通过改变子空间法的Hankel矩阵的分解方法提高计算速度。文中仅用响应数据形成子空间法的脉冲响应矩阵。通过仿真分析验证方法的有效性。

On-Line Identification of Physical Parameters at Joint in Time-Varying Structure System Based on Subspace and Substructure Method

An on-line parameter identification method used to identify physical parameters at joint in moving structure is presented. There are two steps in the identification process. First, eigenvalues and eigenvectors of time-varying system are identified in real time with subspace approach and then, physical parameters at joint in structure are estimated on the basis of the eigen pairs obtained by using substructure method. Computing speed of the algorithm is increased by modifying the decomposition method for Hankel matrix, and the pulse response matrix of subspace is built only by response data. The method is testified to be effective by numerical simulation.