Nidec 22765-01, Руководство пользователя

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Page 6
Construction and Operating Principles
Stator
The stator consists of the supporting frame, core, and armature
windings.
The stator core is made from laminations, thin sheets of electrical steel,
which are stacked and held in place by steel endrings and support
bars. The rings and bars are welded to or are part of the steel frame.
Base mounting plates are welded to the bottom of the frame. The base
mounting plates allow the assembly to be mounted on the genset base.
The windings (coils) are constructed of layered and insulated copper
wire. The coils are inserted in the core slots, connected together, and
the entire assembly is vacuum-pressure impregnated with resin. Stator
leads terminate in standard connection lug or strap terminals for ease of
connection to the load.
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
(four, six, eight or 10). With six or more poles, the poles are typically
attached to a center hub.
The rotor windings consists of insulated magnet wire wound around
each pole. V-blocks 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.
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. The rotor either has resin applied during the
winding process or 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, exciter
armature, and optional 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.
Bearings
The generator may contain either one or two bearings. Bearings
are typically ball or roller type and are regreasable bearings, which
contain fill and drain ports for easy lubrication. Sleeve bearings are
optional on some designs. A supplementary instruction will be included
in the manual package for sleeve bearings if they are applicable to
this generator. Some smaller generators may use heavy duty double
shielded bearings, which are typically used on smaller generators and
are greased for life.
NOTE: For specific lubrication instructions,
always refer to the bearing lubrication
sheet that came with your manual or the
lube plate on the generator.
NOTE: Generators equipped with sleeve
oil bearings must have oil added to
the bearing prior to rotation. Failure to
comply will result in bearing damage. See
the bearing manual.