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AC Generator
Nearly all electrical power in the world is generated by the 3-phase synchronous gen-
erator, which is also known as the ac generator or the alternator. It consists of three
stationary coils (called the stator, armature, or phase coils), which are physically
separated in space by 120° from each other, and a rotor with a dc coil that produces
the dc magnetic eld. Both the stator and rotor coils are individually embedded in
ferromagnetic cores with an air gap that is consistent with the electrical and mechanical
design requirements. Figure4.1 is a simplied cross section of a 3-phase generator with
three stator coils and salie ...