REVERSE POWER RELAY TEST SETUP
For Educational 8& Research insütuions
REVERSE POWER RELAY TEST SETUP NT
DC soURCB
REIY NDICATOR SXNCHROSCOPE
IR ON
SYNC
ON
RST
SPEED INDUCUTER
TEST POL MULTLPUNCTION MTER
V
ORD
CROUE DAGRAN
ALDERNATOR OAD
O O O O O O O
USER MANUAL
Technical clarification/Suggestion:
VERSION-M
JSK LAB INSTRUMENTs
Plot no 16B, Tropical colony,
Thangaraji street,
Pallikaranai.chennai-600100.
Introduction:
Reverse power relay is used to protect the
system duringg
power reversal. When the input to the turbine is
stopped the
generator continues to rotate as a synchronous motor taking
from bus bars and turbine as load. This power
may cause damage to the
system and can be protected. Reverse power protection measures
the power flow from the bus bars to
-
the generator running asa
motor. When the direction of
power flow reverses the relay gets
activated. Time lag is provided in the reverse
that protection does not power protection so
operate during any system disturbances
and power swings.
Reverse power protection is provided in steam turbine,
reciprocating engine, hydraulic turbines gas turbines etc.
PRINCIPIE OF MEASIREMENTS
Active power flowing through a part of an electric circuit is given by
P Vi Cos
Where,
= Phase angle between I and V. The
reactive power is given by VI sin
Region of Region of
Negitive Positive
Cos Cos
180 Vref
For 270°< <+90°, cos is positive and real power P is
so
positive.
For =
90° 180°, real power P is zero.
For +90 << +270°, real power P is negative. So power flow can be sensed by
magnitude and sensing the
sign of V1 cos. The relay used is a directional relay. Voltage coil of is
from secondary of voltage transformer and current coil is supplied
supplied from secondary of current
transformer.
Reverse power relay test
setap
Front panel view:
REVSRSE POWSR RSLAY TESST SETUP
1. VFD drive.
2. Drive
pwm ON/OFFF
3. Speed
adjustment potmeter
4.3phase input terminal
5. Variac for dc
6. Display
voltage adjustment
7. keys
8. Test points
.led indicator for
0. Display
sync panel
1. Circuit diagram
2. MFM
3. Speed indicator
14. Field
voltage
5. Load terminalterminal
SK LAB
Reverse power relay test setup
16. Grid terminal
17. Sensor feedback terminal.
18. Generator terminal.
Block diagram:
CIRCUIT DIAGRAM
P1
m- P2
N1
N2
JSK LAB
Reverse power relay test setup
Wiring diagram:
TO 3 PHASE AC
INDUCTION MOTOR
SETUP
REVERSE POWER RELAY TEST
ARK
RLAY ONATOR
10
7 FROM I PHASE AUTo
ALTERNATOR
TO L.OAD
FROM I PHASE TRANSFORMER OUTPUT
OUTPUT TERMINAL FROM ALTERNATOR TERMINAL
FIELD TERMINAL
JSK LAB
Reversepowerreay
Working procedure:
workingp r o c e d u r e :
connect the wires.
agram
the wiring
1. As per supply turn on.
three phase
2. First then pwm on/off switch turn ON.
drive on.
Now VFD potmeter 50.0 hz.
3. run.now adjus speed adjustment
will and phase
motor
4. Now synchroscope display show frequency,voltage
showing
5. Now or not check.
50 hz coming
angle.frequency
now generator
generate voltage up to 220v set it.
voltage adjust
6. Field dc 220v.synchroscope check two
two source
source
grid voltage
7. Then give three parameters nearest equal
phase angle
voltage,frequency and one not match means
close. Three parameters any
means circuit breaker
close.
circuit breaker not
not synchronized
time note the MFM values.press 'p"
breaker closed that
8. When circuit feeding
is negative means power
button now show power.power
means absorbe the power from grid.
generator to grid.positive
increase ore power
9. Synchronized condition speed adjustment potmeter
delivered to grid.
10.This condition reverse power relay any one button press
11.Set current :2A then enter key press
means go to DMT
12. 1.DMT, 2.IDMT display will come.Press increment key
Mode.
13.Set time:3 sec then press enter button
14.Actual current set current: angle: display will come.
15.This condition actual current compare than set current lovw but relay
not operate this time angle is below 90 degree.
JSK LAB
Reverse power relay test setup
16.Same time reduce the speed using speed
adjustment potmeter. this time
power flow from grid to generator so this time
relay will trip circuit
breaker disconnected.
17.Before reset reverse power relay reduce
grid voltage then reset.
Precautions:
1. Whenfinished the work grid side auto transformer voltage maintain
minimum position.
2. Field variac also maintain minimum position.
3. Pwm ON/OFF switch OFF position.
4. Speed adjustment also minimum position.
Troubleshooting:
1. Any problem means first check all fuses. Any misbehave fuse
the fuse. gone replace
LAB
