A novel threshold segmentation instantaneous frequency calculation approach for fault diagnosis

Instantaneous frequency can well track and reflect the transient information of signal, so it plays an important role in the analysis and processing of the non-stationary signal. In this paper, the single component signal is compared with the Second Order Differential Equation in polar coordinates. Based on this, a threshold segmentation instantaneous frequency calculation method is proposed. This method is mainly for characteristics of the non-stationary signal, use the change of the area around the signal and the x axis to determine the amplitude mutation point of each single component signal, and perform segmentation. Simulations, mathematical derivations and experimental tests are used to highlight the performance of the proposed method. It is not only simple in calculation, but also can reduce the unnecessary influence of non-stationary signal amplitude mutation on instantaneous frequency, and can effectively judge the fault of rolling bearing in fault diagnosis. Keywords: rolling bearings; signal analysis; instantaneous frequency; fault diagnosis; performance