Generac Power Systems CorePower User Manual

PART 2
AC GENERATORS
Page 26
Section 2.2
Operational Analysis
STARTUP
When the engine is started, permanent magnets embedded in
the rotor induce a voltage into (a) the stator AC power windings,
(b) the stator excitation or DPE windings. In an “on-speed”
(engine cranking) condition, this magnetism is capable of
creating approximately one to three volts AC.
ON-SPEED OPERATION
As the engine accelerates, the voltage that is induced into the
stator windings increases rapidly, due to the increasing speed
at which the rotor operates.
FIELD EXCITATION
An AC voltage is induced into the stator excitation (DPE)
windings. The DPE winding circuit is delivered to the voltage
regulator through the two Blue Wires and C1-1 and C1-2.
Unregulated alternating current flows from the winding to the
regulator. The voltage regulator “senses” AC power winding
output voltage and frequency through the Green and White
Wires.
The regulator changes the AC from the excitation winding to DC
Field Excitation. In addition, based on the AC sensing wires,
it regulates the flow of direct current to the rotor. The rectified
and regulated current flow from the regulator is delivered to the
rotor windings through the (+) Red Wire and the positive brush
and slip ring. This excitation voltage flows through the rotor
windings and through the negative (-) slip ring and brush on
the negative (-) Black Wire.
The greater the current flow through the rotor windings, the
more concentrated the lines of flux around the rotor become.
The more concentrated the lines of flux around the rotor that cut
across the stationary stator windings, the greater the voltage
that is induced into the stator windings.
Initially, the AC power winding voltage sensed by the regulator
is low. The regulator reacts by increasing the flow of field
excitation voltage to the rotor until voltage increases to a
desired level. The regulator then maintains the desired voltage.
For example, if voltage exceeds the desired level, the regulator
will decrease the flow of field excitation voltage. Conversely, if
voltage drops below the desired level, the regulator responds by
increasing the flow of excitation current.
AC POWER WINDING OUTPUT
A regulated voltage is induced into the stator AC power windings.
When electrical loads are connected across the AC power
windings to complete the circuit, current can flow in the circuit.
STATOR
EXCITATION
WINDING
VOLTAGE
REGULATOR
STATOR
POWER
WINDING
STATOR
POWER
WINDING
MAGNETIC
FIELD
MAGNETIC
FIELD
MLB = MAIN LINE CIRCUIT BREAKER
ROTOR
SENSING
TO LOAD
MLB
ENGINE -
DIRECT
DRIVE
Figure 18. Operating Diagram

Generac Power Systems CorePower Specifications

General

Brand	Generac Power Systems
Model	CorePower
Category	Portable Generator
Language	English