Dynamic Features of Motor Electrical System in Locomotive Under Excitations of Wheel Polygonization

As a major component of the locomotive, wheels have great importance to realize their functions such as load carrying and power transmission through interactions with the track. However, the polygonised wheels will aggravate the dynamic performance of the locomotive and accelerate the component failures. Monitoring of the wheel polygonization is very important for the locomotive maintenance. In this paper, the effects of the wheel polygonization on the dynamic responses of the traction motor electrical system are analyzed based on the established locomotive dynamics system by considering the electromechanical coupling effect between the mechanical transmission subsystem and the electrical subsystem. The results indicate that the impact effect of the wheel polygonization has a great effect on the vibration of the wheelset and has almost no contribution to the vibration acceleration of the bogie frame, and the characteristic frequency of the lower order wheel polygonization can be found in the frequency spectrum of both the vibration responses of the mechanical system and the electrical signal of the traction motor. And this phenomenon can be used for the monitoring of the wheel polygonization.