There is provided an electric traction system (1), comprising: a step-down transformer (35) comprising a primary winding (36) for operatively coupling to an AC power supply (40) and a secondary winding (37) which is inductively coupled to the primary winding (36); a traction converter module (2) comprising a first input terminal (4) and a second input terminal (6) which are operatively coupled to the secondary winding (37), and a plurality of AC-to-AC power converters (11), each of which comprises first and second input nodes (3, 5) configured to receive AC power and output nodes (9) configured to supply AC power, wherein the first and second input nodes (3, 5) of the plurality of AC-to-AC power converters (11) are electrically connected in series between the first input terminal (4) and the second input terminal (6); and at least one electric motor (25) configured to be driven by the traction converter module (2).