Nidec 22765-01, Руководство пользователя

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Page 7
Connection Boxes
The main lead connection box houses the load lead terminals. In
addition, the generator may have auxiliary connection boxes for
connecting temperature detector outputs, space heater connectors, and
sensing outputs.
Excitation System
The excitation system consists of the exciter stator assembly and the
exciter armature assembly.
The exciter stator assembly consists of windings in a core. The core
is made from steel laminations that are stacked and welded together.
The main exciter stator coils are placed in slots in the core and form
alternate north and south poles. The entire assembly is either mounted
to the end bracket or mounted in a frame, which is mounted to the
end bracket. The stator is a stationary field, which is powered by the
voltage regulator.
The assembly consists of two subassemblies: the exciter armature and
the rotating rectifier. The exciter armature assembly contains steel
laminations that are stacked and keyed on the shaft or on to a sleeve,
which is keyed to the generator shaft. A three-phase winding is inserted
into slots in the laminations. The coils are held in place by insulating
wedges. The coil extensions are braced with tape. Output leads from
the winding are connected to the rotating rectifier assembly.
The rotating rectifier is a three-phase full-wave bridge rectifier,
converting the AC from the exciter armature to DC, which is
transferred to the revolving field windings. Two aluminum steel plates,
each containing three rotating rectifier diodes, are mounted on each
side of an insulating hub to form the negative and positive terminals.
The plates also act as heat sinks for the diodes.
Figure 1 Overview of Excitation System
Output leads
Voltage
regulator
Exciter stato
r
(field)
Main stator
(armature)
Shaft
Main rotor (DC)
Rectifier
Exciter
armature (AC)
PMG stato
r
(armature)
PMG rotor
(field)
Prime mover
Power input