Powertrain system for driving at least one wheel of a vehicle

A powertrain system for driving at least one wheel of a vehicle, comprising:

• a motor having an output shaft;
• a transmission system between the motor and a drive shaft connected to said wheel, the transmission system comprising two epicyclic gear trains each including the following components:
• a ring, a sun, a planet carrier and planet gears, wherein:
• a first epicyclic gear train has a first axis, a component forming a first input component connected to the motor output shaft, and a component forming a first output component;
• a second epicyclic gear train has a second axis parallel to the first axis, a component forming a second input component meshing with the first output component, and a component forming a second output component configured to be connected to the drive shaft,
• wherein the ring, an intermediate part slidably mounted on the outer part of the ring, or the sun of one of the epicyclic gear trains is movable between at least:
• a first position, in which the motor is able to transmit torque to the drive shaft according to a first gear ratio;
• and a second position, in which the motor is able to transmit torque to the drive shaft according to a second gear ratio.