Life prediction of EMU fan bearing based on gray model

The EMU traction motor is a motor that directly drives the wheel to rotate. The matched fan is used to dissipate the heat of the motor to avoid overheating damage. Since the rolling bearing is an important component to support the normal rotation of the traction motor fan, the remaining life of the rolling bearing directly affects the service life of the traction motor fan, which is related to the safe operation of the EMU. In this paper, by extracting the indices of acceleration RMS in the bearing vibration signal, the volatility value of the RMS is slowly increased from 1.7m/s2 to 3.0m/s2, its changing trend is in line with the change rule of rolling bearing life. Therefore, the acceleration RMS is selected as the characteristic index of bearing life prediction, and the GM (1,1) gray model based on the accelerated bearing life test data of rolling bearing is established. Through the acceleration factor, the real remaining bearing life can be calculated by formula. The feasibility of the method is verified by experiments.