Fault diagnosis of cracked rotor using phase wavelet map

Based on the simple hinge crack model, the dynamic equation of a rotor containing transverse crack and initial deflection is modelled in dimensionless form, which can be applied to the vibration analysis of cracked rotor with different parameters at stationary, transient and nonlinear state. By analytical solution, the frequency components of the cracked rotor with initial deflection are analyzed, and the subcritical resonance is discussed. The wavelet transform is introduced into the fault diagnosis of cracked rotor, and the features of phase wavelet map in the cracked rotor are compared with those in the uncracked rotor, which can be used as criteria for identification of cracked rotor. Experiment verifies the validity and feasibility of the proposed algorithm.