A novel modal parameter identification method based on principal component analysis is proposed to improve the operational modal analysis and the independent component analysis
and to decrease the possibility of identifying false modal. The essentiality is to find the relationship between modal shape and linear compound matrix and the relationship between modal responses and principal components. The modal parameter identification is then changed into principal component decomposition. Numerical simulations of two beams with different state show that the new principal component extraction based method is insensitive to Gauss measurement noise
and enables to identify dominant modal shapes and natural frequencies only using vibration time-domain response signals of a structure with measurement noise in despite of system boundary
load type
and load position. The proposed method can be applied to independent modal control method in terms of system recognition and modeling
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