Research on rotor startup condition estimation by using FRFT combined with double PCA

A new method of FRFT combined with double PCA is proposed for the vibration estimation of a startup rotor interfered with simultaneously non-stationary both from the amplitude modulation (AM) and the frequency modulation (FM). In this method, FRFT is used to extract the primary frequency component changed with the rotating speed from an investigated signal. Meanwhile, double PCA is applied for the dimension reduction of a constructed fault feature data set and a speed feature data set. We also provide the principle and the detailed procedure of the proposed method, and the analyses on the actual vibration signal derived from a normal rotor and an unbalance rotor with different degrees are performed. The result shows that the new method not only can identify different running conditions of the rotors, but also can easily observe the evolution process between the normal condition and the unbalance ones with different degrees.