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2018.01 / g
6
Electric Power Generation
Installation and maintenance
R150
AVRs
5384 en -
4 - MAIN FUNCTION OF THE AVR
The AVR is powered by the line-to-neutral terminals of the AC generator with 240 VAC at
50/60 Hz. The regulated sensing voltage is based on the generator line-to-line terminals.
The AVR builds up the generator voltage
from its residual voltage to rated voltage.
When the generator is loaded, the sensed
voltage decreases and generates an error
signal, which is required in order for the
closed loop system to work.
Depending upon the value of the amplified
voltage, the ramp intersects the amplified
voltage at a point which is early or late in the
half-cycle.
At this intersection point, a starting pulse is
produced to trigger the power device.
Only qualified personnel should replace/
work on the AVR.
Do not increase the voltage beyond the
rated voltage.
Options:
Q1 and Q2: CT for parallel operation TI04 (remove ST2)
R1 and R2: 2/2.5 kOhm external potentiometer (remove ST1)
A1 and A2: isolated voltage ± 4.5 VDC
+
-
+
-
2K/2.5K (1W)
7
8
R2
Droop
50 Hz
V
AC
S
UF
OE
SL
UF
OE
60 Hz
R1
A1
A2
Q2 Q1 F2 F1 N
FUSE
W V
ST1 ST2
T1
U1
T4
U2
T3
W1
T6
W2
P2
S2
S1
8
7
P1
TI04
T2
V1
T5
V2
R150
EXCITER
MAIN FIELD
Armature
Exciter field
Varistor
Rotating rectifiers
optional
red or white
black or blue
STATOR: 6 wires (T1 to T6 identification)
yellow
green
blue
Star configuration
Delta
configuration