Design and modelling of asynchronous traction drives fed by limited power source

The paper presents the approaches for design and modelling asynchronous traction drives, fed by limited power source, for railway medium distance journey vehicles or shunt locomotives. The input of the design process is the mission of the vehicle, the rated input voltage of the converter and the maximum motor speed of rotation. The output of the design process is the field of speeds in which the drive can deliver constant power at constant applied voltage, the motor layout and the motor and converter parameters. Using these data the model of the drive has been defined and the transient performance and the system efficiency has been evaluated in all operating conditions in order to facilitate the choice of the degree of hybridisation.