一种分段频域子空间模态参数辨识算法应用

A New Modal Parameter Identification Algorithm with Segment Frequency Domain Subspace and Its Application

针对频域子空间算法在模态参数识别中的使用限制,提出了一种分段计算的频域子空间模态参数辨识方法。该方法对输入和输出的频域数据进行分段,再重新计算广义算子,构成新的状态方程,从而实现模态参数辨识。对该方法进行了仿真验证,并利用该方法对某变截面轴进行了模态参数识别,获得了与有限元计算结果相一致的计算结果,从而证明了方法的可靠性。该方法能够减小单次计算量,从而能够使频域子空间方法在普通计算设备上实现应用。

In order to overcome the application restriction of frequency domain subspace algorithm in modal parameter identification,a new subspace algorithm with segments of frequency domain（SFDS） is put forward in this paper.The SFDS algorithm segments the frequency domain data and re-computes the broad sense arithmetic operators to construct the new state equation and identifies the modal parameters.The simulation validation is carried out.The SFDS algorithm is used to identify the parameters of some variable section shaft.The result is consistent with the finite element result,so it is verified that the SFDS algorithm is effective.It is concluded that the SFDS algorithm can significantly reduce the computation volume,so can be realized on the common computing device.