摘要
本文主要使用頻率域圓嵌合法與時間域亞伯拉罕法兩種系統識別法進行結構系統參數識別,在頻率域法部分由於需使用到結構系統之頻率反應函數,故在文中對於結構系統頻率反應函數之理論與獲得方法作說明,同時並敘述圓嵌合識別法。而在時間域法部分則延續亞伯拉罕識別法,但利用資料時間間距與識別結果關係與遞迴分析法獲取較佳之資料時間間距,同時並使用頻率反應函數之模態識別法扣除較低模態之反應以分析較高模態之參數。文中以數值模擬了單自由度與二自由度結構系統,分別以時間域與頻率域兩種方法進行識別,在頻率域法部分其模態阻尼識別結果誤差較大,模態頻率結果則較好,在時間域法部分經過遞迴分析與頻率反應函數之模態識別法處理後再經由亞伯拉罕法識別結果則較為準確。

there are two main sream methods in system identification,one is time domain method,the other is frequency domain method.In time domain use Ibriahim method ,but in order to reduce time data dt-effect,firsr we should use time-domain iteration to gain more accture data,then use this data to structural identification.In frequency domain we should first gain structural frequency response function ,then use modal testing Nyquist-polt to do system identification.If structural natural frequency is high,use frequency response function modal identification method to cut lower frequency response then use frequency domain method .

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