AC Generators
AC GENERATOR OPERATION
AC GENERATOR OPERATION
Because of the nature of AC voltage and current, the operation of an AC
generator requires that rules and procedures be followed. In addition, there are
various types of AC generators available, each type having advantages and
disadvantages.
EO 1.5
DESCRIBE the bases behind the kW and current
ratings of an AC generator.
EO 1.6
DESCRIBE the conditions that must be met prior to
paralleling two AC generators including consequences of
not meeting these conditions.
EO 1.7
DESCRIBE the difference between a stationary field,
rotating armature AC generator and a rotating field,
stationary armature AC generator.
EO 1.8
EXPLAIN the differences between a wye-connected and
delta-connected AC generator including advantages and
disadvantages of each type.
Ratings
Typical name plate data for an AC generator
Figure 4 AC Generator Nameplate Ratings
(Figure 4) includes: (1) manufacturer; (2)
serial number and type number; (3) speed
(rpm), number of poles, frequency of output,
number of phases, and maximum supply
voltage; (4) capacity rating in KVA and kW
at a specified power factor and maximum
output voltage; (5) armature and field current
per phase; and (6) maximum temperature rise.
Power (kW) ratings of an AC generator are
based on the ability of the prime mover to
overcome generator losses and the ability of
the machine to dissipate the internally
generated heat. The current rating of an AC
generator is based on the insulation rating of
the machine.
Rev. 0
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