MM0704, Lesson 3
Figure 3-11. AC Generator.
armature windings. The exciter output commutator and brushes (4) connect the exciter output directly to the AC
generator field input sliprings and brushes (5). Since these sliprings, rather than a commutator, are used to supply
current through the AC generator field (6), current will always flow in one direction only through these windings.
Thus, a fixed polarity magnetic field is maintained at all times in the AC generator field windings. When the AC
generator field is rotated, its magnetic flux is passed through and across the AC generator armature windings (7).
Remember, a voltage is induced into a conductor if it is stationary and a magnetic field is passed across the conductor,
the same as if the field is stationary and the conductor is moved. The alternating voltage induced in the AC generator
armature windings is connected through fixed terminals to the AC load.
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