THREE-PHASE SYSTEMS
Three-phase generators contain three sinusoidal voltage sources with voltages of the same frequency
but a 120-phase shift with respect to each other. This is realized by positioning three coils at 120
electrical angle separations on the same rotor. Normally, the amplitudes of the three phases are also
equal. The generator is then balanced. In Fig. 11-2, three coils are equally distributed about the
circumference of the rotor; that is, the coils are displaced from one another by 120 mechanical degrees