Effect of unbalanced magnetic pull on the thermal characteristics of traction motor bearing

Purpose The purpose of this paper is to analyze the unbalanced magnetic pull (UMP) of the rotor of traction motor and the influence of the UMP on thermal characteristics of traction motor bearing. Design/methodology/approach The unbalanced magnetic pull on the rotor with different eccentricity was calculated by Fourier series expansion method. A bearing thermal analysis finite element model considering both the vibration of high-speed train caused by track irregularity and the UMP of traction motor rotor was established. The validity of the model is verified by experimental data obtained from a service high-speed train. Findings The results show that thermal failure of bearing subassemblies most likely occurs at contact area between the inner ring and rollers. The UMP of rotor of traction motor has a significant effect on the temperature of the inner ring and roller of the bearing. When the eccentricity is 10%, the temperature can even be increased by about 12 degrees C. Therefore, the UMP of rotor of traction motor must be considered in thermal analysis of traction motor bearing. Originality/value In the thermal analysis of the bearing of the traction motor of high-speed train, the UMP of the rotor of the traction motor is considered for the first time

Automated summary

The study focuses on analyzing the unbalanced magnetic pull (UMP) of the rotor of traction motor and its impact on the thermal characteristics of traction motor bearing. The research involves calculating UMP with different eccentricity and establishing a bearing thermal analysis model that takes into account both track irregularities-induced vibration and UMP. Findings reveal that thermal failure in bearing subassemblies is most likely to occur at the contact area between the inner ring and rollers, with UMP significantly affecting the temperature of these components.