Alternator: Description and Operation

Fig. 1 Exploded View Of A Hitachi Built Alternator:

Fig. 2 Exploded View Of A Mitsubishi Built Alternator:

Alternators are composed of the same functional parts as the conventional D.C. generator but they operate differently. The field is called a rotor and is the turning portion of the unit. A generating part, called a stator, is the stationary member, comparable to the armature in a D.C. generator. The regulator, similar to those used in a D.C. system, regulates the output of the alternator-rectifier system, Figs. 1 and 2.
The power source of the system is the alternator. Current is transmitted from the field terminal of the regulator through a slip ring to the field coil and back to ground through another slip ring. The strength of the field regulates the output of the alternating current. This alternating current is then transmitted from the alternator to the rectifier where it is converted to direct current.