Dynamic analysis of traction motor in a locomotive considering surface waviness on races of a motor bearing

Abstract

The traction motor is the power source of the locomotive. If the surface waviness occurs on the races of the motor bearing, it will cause abnormal vibration and noise, accelerate fatigue and wear, and seriously affect the stability and safety of the traction power transmission. In this paper, an excitation model coupling the time-varying displacement and contact stiffness excitations is adopted to investigate the effect of the surface waviness of the motor bearing on the traction motor under the excitation from the locomotive-track coupled system. The detailed mechanical power transmission path and the internal/external excitations (e.g., wheel–rail interaction, gear mesh, and internal interactions of the rolling bearing) of the locomotive are comprehensively considered to provide accurate dynamic loads for the traction motor. Effects of the wavenumber and amplitude of the surface waviness on the traction motor and its neighbor components of the locomotive are investigated. The results indicate that controlling the amplitude of the waviness and avoiding the wavenumber being an integer multiple of the number of the rollers are helpful for reducing the abnormal vibration and noise of the traction motor.

Dynamic Influence of Wheel Flat on Fatigue Life of the Traction Motor Bearing in Vibration Environment of a Locomotive

“…The single−stage spur gear transmission is widely employed in gear transmissions in locomotives [8][9][10][11][12]21,22,27]. The traction torque generated from the traction motor is transmitted to the wheel-rail interface via the flexible teeth deformation of the gear pair along the line of action which is represented by a spring-damper element (K m , C m ).…”

“…Chen et al [8] further considered the power transmission path of the locomotive and developed a locomotive−track coupled dynamics model with gear transmissions to research the dynamic responses of the gear transmissions and the influence of the tooth root crack on the whole coupled system. Liu et al [9][10][11] and Wang et al [12], respectively, analyzed the dynamic and thermal characteristics of the motor bearings in the vibration environment of a locomotive or a high−speed train.…”

Measured load spectra of the bearing in high-speed train gearbox under different gear meshing conditions

“…Wang et al [15,16] developed a comprehensive vehicle-track coupled dynamics model and investigated the influence of wheel-rail excitation on the axle box bearing load. Liu et al [17,18] discussed the effect of surface waviness and rotor eccentricity on the motor bearing load by using a locomotive-track spatially coupled dynamics model with detailed traction power transmissions. To measure the load of the tapered roller bearing in the wind turbine gearbox, four equally spaced axial grooves were machined in their outer rings and eight strain gauge pairs were used by Keller and Guo et al [19][20][21][22].…”

Dynamic modeling of a metro vehicle considering the motor–gearbox transmission system under traction conditions

“…Therefore, the gear transmission system should attract more significant attention. Since the gear mesh stiffness is one of the internal excitations of the gear transmission system, the methods, such as the finite element method (FEM) (Ma et al, 2015), the experimental method (Raghuwanshi and Anand, 2018), the analytical-FEM hy-brid method (Chen et al, 2019), and the analytical method (Mohammed et al, 2015;Chen et al, 2017a) have been used to obtain the gear mesh stiffness. Generally, the advantage of the analytical method in computational efficiency makes it more popular and noteworthy.…”