Investigation of electromechanical coupling vibration characteristics of an electric drive multistage gear system

In order to investigate the electromechanical interaction mechanism, a dynamic model of an electric drive multistage gear system is established, wherein the electromagnetic characteristics of the induction machine and the translational-rotational vibration of the gearbox are considered. The influence of the electromagnetic effect on the natural vibration characteristics of the gearbox is studied. An integrated method using Campbell diagram, modal energy and speed sweep analysis is presented to identify the resonances of the electromechanical system. The spectrum characteristics of the mechanical signals and the electrical signals are also compared. The results demonstrate that the magnetic field introduces a new vibration mode to the gearbox and changes the low-frequency torsional vibration characteristics of each component. The system investigated in this study exhibits resonance risk when the rotor speed approaches 989 r/min, and it requires special attention during actual operation. When mechanical resonance occurs, recognizable shape features appear in the spectrum of the current and electromagnetic torque. This study supplies some guidance to the design, speed adjustment, and monitoring of electric drive gear systems. (C) 2017 Elsevier Ltd. All rights reserved.