Electronically commutated electric machine having a rotor with salient poles

摘要

Stator field winding (5) is placed at a stator core (1) so that the entire magnetic flux through the lateral side of the rotor (6) due to an operating electric current flowing through stator phase windings (2) is embraced by the stator field winding (5). The stator field winding (5) is composed of at least a first stator field part-winding (5a) which is shunted by a capacitor (C) and connected between an upstream connection terminal (U) of the electric machine and the downstream ends of all stator phase windings (2), each time through a rectifying element (DR, DS, DT) conducting the electric current towards the upstream connection terminal (U) of the electric machine. At least a part of the magnetic field energy as present in the magnetic circuit before commutation is transformed into the magnetic field energy in the magnetic circuit after commutation has been performed. The electric machine according to the invention operates with wider air gaps between stator and rotor poles; therefore no considerable reactive power is either consumed or generated and, owing to the narrow air gaps, there are no difficulties in its fabrication. Its operating life is long. The electromagnetic compatibility is enhanced. <IMAGE>