A Bearing Fault Diagnosis Method Using Deformable Periodic Potential System

A bearing fault diagnosis method using the deformation periodic potential system (DPPS) is proposed to solve the problem that the bearing fault signal is difficult to detect in a high-intensity noise environment. The method first inputs the noise-doped fault signal into the DPPS to form a stochastic resonance (SR) system with DPPS as the core and to detect the bearing fault characteristic frequency from the environmental noise and judge the bearing fault type. Then, the spectral power amplification (SPA) and amplitude response are used as measurement indicators to quantify the enhancement effect of the method on the bearing fault characteristic signal. Analytical formulas of SPA and amplitude response are derived using the method of moments and the probability flow method, and the optimal setting parameters of the DPPS diagnosis method are obtained when SPA and amplitude response are maximum. Finally, the DPPS diagnosis method is applied to the fault diagnosis of bearing inner and outer rings, and compared with the bearing fault diagnosis method that uses the novel combined exponential tristable potential system (NCETS) under the same conditions. Experimental results show that the DPPS diagnosis method uses the noise energy to increase the power spectrum amplitudes of fault characteristic frequency of inner and outer rings to 1 950 and 2 950 respectively. Therefore, it can be easily identified in the power spectrum and then faults of the inner and outer rings of the bearing can be detected. While the NCETS diagnosis method can only increase them to 359.2 and 575.6 respectively. The effectiveness and advancement of the bearing fault diagnosis method using DPPS are proved. © 2020, Editorial Office of Journal of Xi'an Jiaotong University. All right reserved.