Dual excitation electrical machine, and especially motor vehicle alternator

摘要

A flux commutating electrical machine includes a stator and a rotor, the stator including at least one armature coil housed in at least one pair of notches and the rotor selectively establishing closed magnetic circuits around sections of the armature coil(s). At least one excitation permanent magnet establishes a magnetic flux in a circumferential direction of the rotor and at least one excitation coil establishes a localized variable magnetic flux in the same circumferential direction as the flux produced by the magnet(s). The magnet or each magnet is housed in a first rotor part defining a first pair of rotor poles, the coil is or the coils are housed in a second rotor part defining a second pair of rotor poles and the rotor parts are separated from each other by essentially magnetically non-conductive areas.