Torsional vibration assessment in railway traction system mechanical transmission

The diagnosis of mechanical anomalies in railway traction system (RTS) have significant importance on traction system safety and reliability, which can avoid train derailment. This paper deals with torsional vibration assessment in mechanical transmission of RTS by a non-invasive technique. The previous studies on an elementary gearbox-based electromechanical system have shown that the influence of gearbox torsional vibration in torque and stator current signatures. It will be demonstrated here that in RTS the traction motor can be considered as a torque sensor through electromagnetic torque estimation for torsional vibration monitoring without any extra mechanical sensor. The results of estimation are compared with the measured mechanical torque and validated through a reduced-scale RTS simulator in stationary and non-stationary conditions.