Indirect friction force identification for application in traction electric drives Original Research Article

The skidding phenomenon in railway traction is analysed, a procedure for indirect identification of friction force is proposed and the results obtained from the procedure are experimentally validated. Validation is achieved through testing of a scale model of a E402 locomotive. The scale model is presented. The derivative of friction force with respect to time can be assumed as a parameter to deduce skidding, but is insufficient to realise anti-skidding control. The purpose of the control is both to keep the force between wheel and rail near the maximum of adhesion and to prevent slip-stick oscillation.