Propulsion system for a multiple-voltage locomotive

A propulsion system for a multiple-voltage locomotive, having a drive transformer (2); a high-voltage stage (3); an inverter (5); and a charge storage device between the output of the high-voltage stage (3) and the inverter (5). The propulsion system provides for a first operating configuration, in which the primary winding (Tp) of the transformer (2) receives an alternating line voltage, and the secondary winding (Ts) of the transformer (2) communicates with an input of the high-voltage stage (3) operating as a controlled rectifier. The propulsion system also provides for a second operating configuration, in which the inputs of the high-voltage stage (3) receive a direct line voltage, and the secondary winding of the transformer (2) is interposed between an output of the high-voltage stage and an input of the inverter (5). In the second operating configuration, the primary winding of the transformer is short-circuited.