Copyright ® Siemens Power Generation, Inc. 2007.
All rights reserved
Seite 1 Jan 2007 Michael Wegen PG OE31
Overview GT, Generator and Auxiliaries
System Color
SGT5 – 4000F
Seal Air System
(MBH)
Hydraulic
System (MBX)
Purge Water
Syst. MBN80
Fuel Oil System
(MBN)
Fuel Gas System
(MBP), (MBQ)
Instrument Air
System (MBX21)
Water – System
(MBU/NOx/Emu)
Lube & Lift Oil
System (MBV)
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 2 Jan 2007 Michael Wegen PG OE31
Overview GT Protection Measuring Instruments
System
5. Surge Protect. 5. Fame Monitors 3. Casing Vibration Indicators 6. TOT / Exh. Press.
10. Humming / Accel. 4. Bearing Metal Temperature
2. Speed Sensors
Seal Air T/Press.
HP Hydraulic Press.
Purge Water Press.
9. Fuel Oil Press. / T.
8. Fuel Gas Press./ T.
Water Press. / Temp.
Instrument Air Press
SGT5 – 4000F 1. Lube Oil Pr. / ELP
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 3 Jan 2007 Michael Wegen PG OE31
Safety and Protection Systems
SGT5 – 4000F ( V94.3A )
In the following the
most important
1. Lube oil pressure / Schmieröldruck
Safety and Protection
systems are listed and 2. Over – Speed / Überdrehzahl
described in brief:
3. Vibration – Protection / Schwingungsüberwachung
4. Bearing temperature / Lagertemperatur
5. Surge protection / Pumpschutz
6. Turbine outlet over – temperature / TAT – Schutz
7. Flame monitoring / Flammenüberwachung
8. Fuel gas pressure / Heizgasdruck
9. Fuel oil pressure / Heizöldruck
10. Humming, Acceleration / Brummen, Beschleunigung
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 4 Jan 2007 Michael Wegen PG OE31
1. Lube Oil Pressure, Emergency Lube Oil Pump
Schmieröldruck, Notölpumpe
The Emergency Lube oil Pump comes
into operation under the following conditions:
Î Loss of 380V supply
Î Low Lube oil pressure via 24V and 220V pressure switches
e.g.: if lube oil pressure drops below via PS MBV26 CP001*/002
( supply pressure < min P.SCMOEL.01 ) and/or below 1,0 bar via PS
MBV26 CP003 ( DC direct ) / *Aux. p. and Emerg. Lube Oil p. ON, no delay
If CP001 and 002 < min Æ GT-Trip, delayed by K.SCHMOEL.05; 002* no delay
Î Level lube oil tank << min
Î Manual command ON ( is always possible )
Î Testing logic within Start/Stop-Program
Î Fire alarm ( an OFF – Command by hand is always possible )
308-002-02/308-001-01
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 5 Jan 2007 Michael Wegen PG OE31
2. Over – Speed Protection
Überdrehzahlschutz
The over-speed protection is realized by six (6) speed sensors. Two channels three sensors each.
A over-speed trip signal will be initiated under the following conditions:
If one sensor (1 out of 3) out of one channel signals over-speed
No Trip Æ but an alarm
If two sensors (2 out of 3) out of one channel signals over-speed
Trip of GT and alarm
Remark:
• A SGT5 has 36 grooves in the shaft, SGT6 has 30, SGT – 1000 has 20.
Æ for example a SGT5 – 4000F: 36 multiplied by 50 Hz are 1800 impulses/s
• A Trip-Signal will be initiated when the Turbine reaches a speed of 108%
• Over- / Underfrequency protection [ S.TURB.95 e.g. 51.5 Hz ]
314 – 011 – 02
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 6 Jan 2007 Michael Wegen PG OE31
3. Vibration – Protection
Schwingungsüberwachung
Vibration indicators are located at:
z Turbine bearing casing
z Compressor bearing casing
z Generator bearing casing ( Turbine side )
z Generator bearing casing ( Exiter end )
Remark: Alarm value = 9,3 mm/s (eff)
Trip value = 14,7 mm/s (eff)
In addition there are ( could be ) two shaft vibration indicators
Alarm value = 165 µm/s (rel)
mounted at the Turbine, Compressor and Generator bearing each. Trip value = 260 µm/s (rel)
ISO 10816-4(CT) for absolute casing vibrations [ mm/s, rms ]
ISO 7919-4(CT) for relative shaft vibrations [ µm, pp ]
314 – 008/010
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 7 Jan 2007 Michael Wegen PG OE31
4. Bearing Temperature Protection
Lagertemperaturschutz
Thermocouples are located at all bearings:
z Turbine bearing
z Compressor bearing ( combined, includes thrust bearing )
z Thrust bearing ( front and rear, upper and lower part )
z Generator bearing, turbine side
z Generator bearing, exciter end
[ V64.3A Gear box is additionally equipped with TC ]
Alarm value = 100°C
Trip value = 120°C
314-001
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 8 Jan 2007 Michael Wegen PG OE31
5. Surge Protection
Pumpschutz
The Turbine is protected against surging by
three differential pressure switches which are
located at the compressor inlet.
A Trip-Signal is being initiated under
the following conditions:
Turbine speed > 2520 rpm (50 Hz CT) AND
(MBA 11 CP 001/002/003/ 2 out of 3) < 30 mbar.
Î Compressor Ratio Limit Controller
Î Compressor Gradient Limit Controller
314-013-02
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 9 Jan 2007 Michael Wegen PG OE31
6. Turbine Outlet Over-Temperature Protection
Turbinenaustrittstemperatur, Übertemperaturschutz
The turbine outlet temperature is measured by 24 thermocouples ( three elements each ).
• A-elements are for
temperature control There are three possibilities:
• B and C-elements are
for protection 1. Over temperature in the whole combustion chamber
z Thermocouples MBA 26 CT 101/105/109/113/117/121 element B
3 out of 6 TC’s – Alarm at 50K + actual BL OTC
3 out of 6 TC’s – GT Trip at 90K + actual BL OTC
( final set according to base load OTC, PL not considered )
2. Hot Spot ( Single burner too much fuel ), release: 300°C turbine outlet temperature and speed > 47,5 Hz
z MBA 26 CT 101…124 element B and C
One thermocouple ( B+C ) > turbine outlet t. ( average ) + 30°C … Alarm
One thermocouple ( B+C ) > turbine outlet t. ( average ) + 50°C … GT-Trip
3. Cold Spot ( One or more burner no flame, release at speed > 47,5 Hz and TOT > 300°C )
z MBA 26 CT 101…124 element B and C
Two thermocouples side by side < TOT ( average ) - 50°C … Alarm
Three thermocouples side by side < TOT ( average ) - 50°C … GT shut down program
Four thermocouples side by side or
two, groups with 2x3 thermocouples < TOT ( average ) - 50°C … GT-Trip
314-003/014
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 10 Jan 2007 Michael Wegen PG OE31
TC’s at Turbine Oulet
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 11 Jan 2007 Michael Wegen PG OE31
7. Flame Monitoring
Flammenüberwachung
The
Thecombustion
combustionchamber
chamberisisequipped
equippedwith
withtwo
twoflame
flamesensors.
sensors.
Setting
Settingof
ofthe
theflame
flamemonitors
monitorsisisperformed
performedduring
during
the
the ignition gas tests during the first startup.
ignition gas tests during the first start up.
AAturbine
turbinetrip
tripisisinitiated
initiatedififboth
bothflame
flamesensors
sensorsdetect
detectNO
NOFLAME
FLAMEduring
duringoperation.
operation.
IfIfonly
onlyone
oneflame
flamesensor
sensordetects
detectsNO
NOFLAME
FLAMEan
anAlarm
Alarmisisinitiated.
initiated.
331 - 009
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 12 Jan 2007 Michael Wegen PG OE31
8. Fuel Gas Pressure
Heizgasdruck
GT
GTisisequipped
equippedwith
with33pressure
pressuretransmitters
transmittersto
tomonitor
monitorthe
thegas
gaspressure
pressure
22upstream
upstream( (MBP13
MBP13CP101/102
CP101/102) )and
and11downstream
downstream( (MBP14
MBP14CP101
CP101) )of
ofthe
theESV
ESV
For
Forpilot
pilotgas
gasmonitoring
monitoring22upstream
upstream( (MBP15
MBP15CP101/102
CP101/102) )( (an
anoption
optionfor
forGT
GTwith
withPG-ESV
PG-ESV) )
Gas
Gaspressure
pressurehigh
highininall
alloperation
operationmodes
modes… …Alarm
Alarmonly
only
Gas
Gaspressure
pressurelow
low( (P.GAS.06
P.GAS.06/ /22out
outof
of33) )ininall
allmodes
modes......Alarm
Alarm
Gas
Gaspressure
pressurelow
low (p
(p<<min)
min) …
…Alarm,
Alarm,nonorelease
releasefor
forchange
changeover
overfrom
fromdiffusion
diffusion
to
to premix, interruption of the fuel changeover
premix, interruption of the fuel change over
from
from fuel oil to gas operation ( pGas > pVII! !) )
fuel oil to gas operation ( pGas > pVII
FG
FGTwo
TwoStage
StageBurner:
Burner:NoNochange
changeover
overfrom
fromPM
PMto
toDM,
DM,Premix
Premixmode
modeover
overthe
thefull
fullload
loadrange
range
Gas
Gaspressure
pressuretoo
toolow
low( (pp<<
<<min
min/ /P.GAS.07
P.GAS.07und
und17
17) )…
…GT-trip
GT-trip
[ [No
Nopressure
pressurelimit
limitduring
duringfuel
fuelgas
gasdiffusion-mode,
diffusion-mode,can
canbe
becompensated
compensatedby
bycontroller
controller] ]
Logic:
Logic:22out
outof
of33for
foralarm
alarmand
andtrip,
trip,monitoring
monitoringof
ofpressure
pressuredeviation
deviationbetween
betweenpr.
pr.transd.
transd.
312 – 021 -02
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 13 Jan 2007 Michael Wegen PG OE31
9. Fuel Oil Pressure SGTX – 4000F / VX4.A2
Heizöldruck
Diffusion System
Min-pressure ( P.HOE.01 / MBN13 CP101/102/103 ) downstream of the pump(s) is the release for opening of ESV
Differential pressure between diff. oil feed line ( MBN14 CP101/103 ) and compressor outlet ( MBA12 CP101/102 )
less than min ( specified setting PP.HOEDB.09 ) → Trip
Premix System
If Differential pressure between premix oil feed line ( MBN23 CP101/102 ) and compressor outlet
( MBA12 CP101/102 ) less than min ( PP.HOEVB.07 ) → partial trip of the premix system
Leak Oil
Seal air ball valves in the feed lines are equipped with leak oil pipes
leak oil pressure diffusion system: MBN34 CP001..3 (2 out of 3) > 1,5 bar → Trip
leak oil pressure premix system: MBN44 CP001..3 (2 out of 3) > 1,5 bar → Premix Trip
*Special settings for each turbine are in the SREL ( List of Control Settings )
311-039-01 / 311-022
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 14 Jan 2007 Michael Wegen PG OE31
10. CC Acceleration / BK – Beschleunigung
Æ Two dynamic pressure transducers and two acceleration sensors are monitoring the instability of combustion.
Æ In fuel gas mode the acceleration monitoring system is being used only. It does not apply to SGT – 1000
Æ In fuel oil mode both systems are monitoring the combustion instability.
Æ Different limit values depending on the type of gas turbine.
Æ Limit values 1 and 2 will be active with turbine speed > S.TURB.70 ( e.g. 47 Hz ) for a SGT5 – 4000F (V94.3A)
Limit values humming acceleration
GW1 P.BRUMM.01 Fuel Gas / Fuel oil S.ACC.01 Fuel Gas ( 2,5g RMS )
25 mbar S.ACC.04 Fuel Oil ( 2,5g RMS )
GW2 P.BRUMM.02 Fuel Gas / Fuel oil S.ACC.02 Fuel Gas ( 3,0g RMS )
40 mbar S.ACC.05 Fuel Oil ( 3,0g RMS )
GW3 P.BRUMM.06 Fuel Gas / Fuel oil S.ACC.03 Fuel Gas / Fuel oil ( 8,0g RMS )
80 mbar
GW4 S.ACC.07 ( 1,5 g RMS, 0.5s delay, IGV>95% )
331-016
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 15 Jan 2007 Michael Wegen PG OE31
10. Humming and acceleration protection
Brummen und Beschleunigung
Æ Measures
Æ Load reduction
SGTX – 4000F ( VX4.3A ), fuel gas operation, CC with CHS
GW1 after K.ACC.01 ( 4s) load shed by E.LEIST.32 (6 MW)
repeated every K.BRUMM.05 ( 4s )
GW2 after K.ACC.02 (1s) one load shed by E.LEIST.33 (15 MW)
GW4 Load shed by 6MW ( 1,5 ...1,8g delay 0,5s, release IGV > 95% ),
2,0g for Kureimat which is equipped with a two stage burner
Æ GT-Trip
SGTX – 4000F ( V94.3A ), fuel gas operation, CHS
GW1 Trip after K.BRUMM.03 ( 15s ) + K.ACC.01 ( 4s )
GW2 Trip after K.BRUMM.04 ( 12s ) + K.ACC.02 ( 1s )
GW3 Trip after K.ACC.04 ( no time delay ) ⇒ CC inspection
331-016
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 16 Jan 2007 Michael Wegen PG OE31
Further Protection Sytems
Generator Trip Signal(s)
Boiler Trip Signal(s) ( Combined Cycle Power Plants )
Burner Temperature at Axial Swirler
Oil Pressure hydraulic Skid ( MBX ) too low
Instrument Air Pressure ( MBX2_ ) too low
NOx Water
Purge Water
Burner Seal Air
Pressure / Temperature GT Enclosure
Compressor Air Inlet Damper
Differential Pressure Filter House too high
Water Level too high inside Generator ( Air to Water cooled Generator )
Copyright ® Siemens Power Generation, Inc. 2007. All rights reserved
Seite 18 Jan 2007 Michael Wegen PG OE31
