Electric traction 2 Traction (friction) 2 Traction control 2 Traction drive Asynchronoi electric motor 1 Control systems 1 Controllers 1 Direct torque control 1 Drive control 1 Elastic waves 1 Electric impedance measurement 1 Electric traction drive 1 Energy efficiency 1 Engines 1 Field-oriented control 1 Induction motors 1 Load disturbances 1 Machine vibrations 1 Nominal frequency 1 Power load 1 Power supply 1 Proportional resonant controllers 1 Railroads 1 Rails 1 Railway traction 1 Railway traction drive 1 Railway traction drives 1 Slip control 1 Slip-stick phenomenon 1 Stick-slip 1