Dynamic Characteristics Study of a Typical Electric Powertrain System

The electric powertrain system consisting of electric motor (EM) and multi-stages planetary gearbox is a classical solution for automatic driving, both the driving capacity of EM and the mechanical features of gearbox should be systematically studied. In this paper, an electromechanical coupled modelling strategy was proposed using lumped method. Firstly, the driving model of three-phases asynchronous EM was built under rotor flux oriented control. Subsequently, the force transmissions between all coupled elements are investigated by analyzing the rotational and translational dynamics of planetary gear train, the radial bearing vibration characters of different gears under meshing force are also studied as typical spring damping mass system, and the time-varying meshing stiffness and nonlinear backlash between every meshing pairs are considered. Finally, the dynamic features of the gear train are comparatively studied with different gear teeth number configuration to eliminate the system vibration. The simulation results show that dynamic characteristics of this powertrain system have the frequency features of carrier revolution and the meshing harmonics, and odd teeth configuration is preferred to compress the working rotational vibration mode.