A synchronous multipolar brushless machine includes an immobile stator armature and field windings, which are placed concentrically around a shaft and radially inwardly positioned relative to the stator armature, on a power unit carrying disc, so that the field windings and armature windings form a mechanically connected unit which generates an excitation magnetic field, and in which an alternate voltage is generated. The excitation magnetic field is transferred to a rotor via labyrinth shaped first and second air gaps. A multipolar rotating magnetic field is generated around the stator armature while the synchronous machine is operated, thereby magnetizing the rotor. In order to reduce magnetic flux resistance, a ferromagnetic tolerance ring is inserted in each first and second air gap. Alternatively, a ferrofluid is provided in each first and second air gap, which significantly increases the magnetic conductivity.