| Abstract: | The identification result of operational mode is eurychoric while operational mode identification is investigated under ambient excitation,which is influenced by the signal size and the time interval. The operational mode identification method,which is based on the sliding time window method and the eigensystem realization algorithm(ERA),is investigated to improve the identification accuracy and stability. Firstly,the theory of the ERA method is introduced. Secondly,the strategy for decomposition and implementation is put forward,including the sliding time window method and the filtration method of modes. At last,an example is studied,where the model of a cantilever beam is built and the white noise exciting is input. Results show that the operational mode identification method can realize the modes,and has high robustness to the signal to noise ratio and signal size. |
