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Rotor
The main rotor assembly is the revolving field. It consists of windings
in a core, which is in turn mounted on a steel shaft. The exciter
armature assembly and permanent magnet generator (PMG) rotor
are also mounted on the shaft as are the fan(s) and other optional
accessories. The core consists of laminations, thin sheets of electrical
steel, which are stacked together. The core makes the salient poles. See
Figure 6.
The rotor windings consist of insulated magnet wire wound around
each pole. V-blocks or spreader bars between each pole keep the rotor
windings in place. Damper windings consist of copper or aluminum
rods that are inserted through each pole surface and are brazed to
copper or aluminum damper end plates at each end of the lamination
stack.
Figure 6 Generator Rotor
The end plates are brazed to adjacent poles to form a continuous
damper winding. The ends of the windings are supported with bars or
aluminum pole shoes. Some designs have neither end shoes or plates.
The rotor is vacuum-pressure impregnated with resin.
The shaft is made from high-strength rolled or forged steel and
machined to accommodate all the rotating generator components.
Keyways in the shaft ensure precise positioning of the rotor, fans,
exciter armature, and PMG rotor as well as drive couplings. On the
exciter side, the shaft has a slot or hole in its centerline for running the
revolving field leads to the rectifier.
Summary of Contents for 4P10
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