Abstract: A self-excited brushless alternator having a rotating field excited by an alternating current exciter whose armature rotates with the field winding of the alternator and is permanently connected to that winding by a rotating field rectifier. To obtain reliable regulation over a wind range of load and power factors, at least one exciter stator primary winding is magnetically coupled to at least one exciter rotator secondary winding which is connected by the rectifier to the main field. Primary excitation direct current for the exciter is derived by a magnetic coupling from a rotary auxiliary magnetic field produced by a feedback winding connected in series with the main field winding and rotating therewith. Preferably, current paths for the exciter primary excitation are different during and after build-up.