Application of grey relation degree in rotor´s fault identification

After deeply researching the relation between reason and symptom of rotor´s fault, a novel fault identification method is proposed based on grey relation degree. Firstly, the sampled data is transformed by FFT in frequency domain. Secondly, the interested frequency band is selected by harmonic window decomposition. Thirdly, the energy distribution of each frequency band is calculated. Different fault type corresponds with different energy distribution. Finally, the grey relation between the symptom set and standard fault set is calculated as the identification evidence for fault diagnosis. The practical results show that this approach is quite efficient. It´s suitable for on-line monitoring and diagnosis of rotating machinery.