Incipient fault information determination for rolling element bearing based on synchronous averaging reassigned wavelet scalogram

• Synchronous averaging reassigned wavelet scalogram method is proposed.
• The proposed method is helpful to determine weak impact fault.
• Simulation results confirmed this proposed method.
• Weak fault determination for rolling element bearings verify the effectiveness.

As incipient fault of rotating machinery is weak and interfered by noise, it is difficult for characteristic information determination and incipient classification. In this research, a new method is put forward on rolling element bearing (REB) incipient impact information using synchronous averaging reassigned wavelet scalogram (SARWS) according to time–frequency analysis. Firstly, multi-cycle signal is processed by continuous wavelet transform. Then, time frequency distribution for every working cycle of vibration signal is obtained by wavelet scalogram (WS) based on time domain information. Thirdly, reassigned wavelet scalogram (RWS) for every working cycle of REB can be calculated. In the end, synchronous averaging is applied on RWS, which can effectively reduce noise interference and identify the weak fault information. Both simulated signals and real vibration signals collected from REB of rotating machinery are used to verify this proposed method. Analyzed results show that the proposed method is effective for REB incipient weak fault classification.