OPERATING SEQUENCE OPERATING SEQUENCE
The following flow chart pertains to typical operation of a Frame 6 gas turbine unit designed The following flow chart pertains to typical operation of a Frame 6 gas turbine unit designed for generator drive application.
for generator drive application. The differences from unit The differences from unit to unit (which are to unit (which are based on based on thethe specific requirements of each unit) are not discussed here. Refer to the project or unit specific requirements of each unit) are not discussed here. Refer to the project or unit specific documentation for more details.
specific documentation for more details.
Operational information includes startup and shutdown sequencing in the auto mode of Operational information includes startup and shutdown sequencing in the auto mode of operation. This is intended to cover normal operation and assumes that initial startup, operation. This is intended to cover normal operation and assumes that initial startup, calibration and checkouts have been completed and that the turbine is in the stand by mode calibration and checkouts have been completed and that the turbine is in the stand by mode ready for operation with ac and dc power available for all equipment, and all annunciators ready for operation with ac and dc power available for all equipment, and all annunciators are cleared.
are cleared.
The following flow chart lists operator control system and machine actions or events in the The following flow chart lists operator control system and machine actions or events in the starting sequence of the gas turbine.
All Trip functions are checked to be in the “ Not Tripped” and reset All Trip functions are checked to be in the “ Not Tripped” and reset Protection System Checks Ready to Start Permissive
Protection System Checks Ready to Start Permissive 1.
1. Generator Generator Lockout Lockout relay relay is is resetreset 2.
2. Turbine Turbine is is at at zero zero speedspeed 3.
3. Lube Lube oil oil tank tank temperature temperature is is normalnormal 4.
4. Over Over speed speed bolt bolt is is not not trippedtripped 5.
5. Flame Flame is is not not detected detected in in all all the the scannersscanners 6.
6. OFF OFF is is not not selectedselected 7.
7. Fuel Fuel valve valve is is closed closed an an lockout lockout resetreset 8.
8. Compressor Compressor or or bleed bleed valves valves are are openopen 9.
9. IGV’s IGV’s are are closedclosed 10.
10. Master Master Protective Protective “4” “4” logic logic is is resetreset 11.
11. <R> <R> , , <S> <S> and and <T> <T> Master Master Protective AgreeProtective Agree 12.
12. Emergency Emergency Lube Lube oil oil Pump Pump voltage voltage is is normalnormal 13.
13. Diesel Diesel Test Test is is not not in in progressprogress 14.
14. Off Off line line diagnostics diagnostics are are not not in in progressprogress 15.
15. <R>, <R>, <S> <S> and and <T> <T> communication communication links links healthyhealthy 16.
16. Generator Generator breaker breaker is is openopen 17.
17. Diesel Diesel warm warm up up timer timer resetreset 18.
18. Multiple Multiple starts starts counter counter resetreset
“Auto
“Auto Start” Start” }} “
“ Startup Startup Statust” Statust” } } DisplaysDisplays “
“ Shutdown Shutdown Status” Status” }} “
“ Off Off Select” Select” }} “SHUTDOWN STATUS” } “SHUTDOWN STATUS” } “
“ Not Not Ready Ready to to Start” Start” } Displays} Displays “Off
“Off Cool Cool Down” Down” }} “
“ Off Off Select” Select” }} Operator presses “ Auto” and then “ Execute”
Operator presses “ Auto” and then “ Execute” LED next to “AUTO” Comes on Steady LED next to “AUTO” Comes on Steady
Operator Selects ‘ Normal ‘ Display Operator Selects ‘ Normal ‘ Display
NORMAL START NORMAL START
Protection system
Protection system checks “ checks “ Start Command” Start Command” permissives:permissives: 1.
1. Base, Peak Base, Peak or Pre-selected or Pre-selected load is load is not not selectedselected 2.
2. <C> <C> Communication link Communication link is is healthy and healthy and resetreset 3.
3. Auxiliary Auxiliary checks checks are are goodgood 4.
4. Starting Starting Device Device trip trip is is resetreset 5.
5. Multiple Multiple start start counter counter is is resetreset 6.
6. Emergency Emergency Push Push button button is is resetreset 7.
7. Stop Stop sequence sequence is is not not in in progressprogress 8.
8. Generator Generator breaker breaker closing closing timer timer is is resetreset 9.
9. Control is Control is not not in in “OFF” m“OFF” modeode
LED next to “ Start” is steady ON LED next to “ Start” is steady ON
“ Manual Initiated Starts” counter incremented “ Manual Initiated Starts” counter incremented Auto Synch permissive is latched
Auto Synch permissive is latched
Turbine speed reference TNR is preset to start value Turbine speed reference TNR is preset to start value Multiple start timer is started
Multiple start timer is started Fast start system is disabled Fast start system is disabled AC lube oil pump is started AC lube oil pump is started
Hydraulic ratchet Pump is started (88HR) – if not done already Hydraulic ratchet Pump is started (88HR) – if not done already Starting clutch solenoid energized (20CS)
Starting clutch solenoid energized (20CS) Jaw clutch is engaged
Jaw clutch is engaged and feedback is and feedback is obtained through 33CSEobtained through 33CSE Master Protective System Energizes ( L4)
Master Protective System Energizes ( L4)
“Start Select” “Start Select”
“ Sequence in Progress” displayed “ Sequence in Progress” displayed “ Off
“ Off Cool Down” Cool Down” goes off goes off
“Starting “ displayed “Starting “ displayed “Ready to
“Ready to Start” Start” goes goes off off Operator presses “ Start” and then “ Execute”
Operator presses “ Start” and then “ Execute” LED next to “ Start” is blinking
LED next to “ Start” is blinking “Ready
“Ready to to Start” Start” displayeddisplayed “Not
Auxiliary Hydraulic Pump is started (88HQ) Auxiliary Hydraulic Pump is started (88HQ) Diesel stop valve is energized (20 DV) Diesel stop valve is energized (20 DV)
Diesel engine cranking motor starts for 5 seconds (88DC) Diesel engine cranking motor starts for 5 seconds (88DC)
Diesel engine starts and Diesel lube oil pressure pickups (63QD) Diesel engine starts and Diesel lube oil pressure pickups (63QD) Total starts counter is incremented by 1
Total starts counter is incremented by 1
On On L
Lii uuiidd??
Distillate Fuel forwarding pump is Distillate Fuel forwarding pump is started:
started:
5 sec later distillate fuel 5 sec later distillate fuel stopstop valve (20FD) is
valve (20FD) is energizedenergized
Liquid Fuel Purge solenoid valve Liquid Fuel Purge solenoid valve (20PL) is de-energized
(20PL) is de-energized
Gas Fuel Trip servo solenoid is energized (20FG) Gas Fuel Trip servo solenoid is energized (20FG)
Liquid Fuel purge solenoid is energized (20PL) Liquid Fuel purge solenoid is energized (20PL)
No No
Diesel engine reaches minimum speed (idle speed) Diesel engine reaches minimum speed (idle speed) Diesel engine goes on 2 minute warm up
Diesel engine goes on 2 minute warm up Warm
Warm up up completes. completes. Diesel engine Diesel engine acceleratingaccelerating
Diesel engine accelerating Solenoid is energized (20DA-2) Diesel engine accelerating Solenoid is energized (20DA-2)
Hydraulic ratchet starts continuous ratchet Hydraulic ratchet starts continuous ratchet Turbine breaks away (L14HR becomes zero) Turbine breaks away (L14HR becomes zero)
Starting clutch solenoid de-energized (20CS) Starting clutch solenoid de-energized (20CS) Hydraulic ratchet pump shutdown
Hydraulic ratchet pump shutdown
NOTE: Jaw clutch is held engaged by the torque of diesel engine NOTE: Jaw clutch is held engaged by the torque of diesel engine Diesel engine reaches its cranking speed (14DC)
Diesel engine reaches its cranking speed (14DC)
Diesel engine accelerating solenoid valve de-energized (20DA-2) Diesel engine accelerating solenoid valve de-energized (20DA-2) Diesel engine cranking speed drops out (14DC)
Diesel engine cranking speed drops out (14DC)
Diesel cranking speed locking solenoid energized (20DA-1) and speed stays Diesel cranking speed locking solenoid energized (20DA-1) and speed stays constant
constant
“ Cranking” displayed “ Cranking” displayed “ Starting” goes off “ Starting” goes off
No Yes No Yes On Gas? On Gas? On On L Lii uuiid d ??
Permissive for SRV to open is enabled Permissive for SRV to open is enabled Permissive for GCV to open is enabled Permissive for GCV to open is enabled
Energizes Liquid fuel trip solenoid (20FL) Energizes Liquid fuel trip solenoid (20FL) Energizes fuel pump clutch solenoid (20CF) Energizes fuel pump clutch solenoid (20CF)
Permissive for Fuel Pump Bypass valve to operate is Permissive for Fuel Pump Bypass valve to operate is enabled
enabled
Fuel Stroke Reference (FSR) is set to Firing Value, which in turn is FSR Fuel Stroke Reference (FSR) is set to Firing Value, which in turn is FSR OUT for Gas and FQROUT for liquid
OUT for Gas and FQROUT for liquid
Auxiliary Turbine Vent timer energized (2TV) Auxiliary Turbine Vent timer energized (2TV) Ignition relay is energized after time out (2TVX) Ignition relay is energized after time out (2TVX) Spark plugs are energized (95SP)
Spark plugs are energized (95SP) 60 second Firing timer is started (2TF) 60 second Firing timer is started (2TF)
No No
Crank Crank Select?
Select? End of SequenceEnd of Sequence No
No
Gas Fuel vent solenoid Gas Fuel vent solenoid is energized (20VG) is energized (20VG)
Turbine Air Inlet separator Motor (88TA) started (if used) Turbine Air Inlet separator Motor (88TA) started (if used)
Turbine accelerates to minimum firing speed (14HM) Turbine accelerates to minimum firing speed (14HM)
No No No No Yes Yes Yes Yes “ Firing” displayed “ Firing” displayed
“Startup Control” displayed “Startup Control” displayed “ Cranking” goes off
“ Cranking” goes off
Flame is Flame is detected in 2 out detected in 2 out of 4 scanned of 4 scanned Flame is steady Flame is steady for 2 sec before for 2 sec before
firing timer firing timer Times out Times out
“ Failure to
“ Failure to Fire” alarm appearsFire” alarm appears
•
• Operator presses “Crank” and thenOperator presses “Crank” and then
“Execute” “Execute”
•
• “Crank” LED comes steady ON“Crank” LED comes steady ON •
• Operator presses “ Fire” or “ Auto” andOperator presses “ Fire” or “ Auto” and
then “Execute” then “Execute”
•
• LED comes steady ONLED comes steady ON •
• Turbine vent timer is started for air Turbine vent timer is started for air
purge purge “ Firin
“ Firing” g” goes goes off off “Warming up” “Warming up” displayed displayed Fire Fire Select? Select?
Warm up timer starts (60 sec) (2W) Warm up timer starts (60 sec) (2W)
Turbine compartment vent fans are started (88BT) Turbine compartment vent fans are started (88BT) Fired hours timer is energized
Fired hours timer is energized
Fired starts counter is incremented by 1 Fired starts counter is incremented by 1
After warm up timer times out, FSR is increased at a predetermined rate to the After warm up timer times out, FSR is increased at a predetermined rate to the accelerate limit FSR
accelerate limit FSR
Diesel engine locking solenoid is de-energized (20DA-1) Diesel engine locking solenoid is de-energized (20DA-1) Diesel accelerating solenoid is energized (20DA-2) Diesel accelerating solenoid is energized (20DA-2)
End of End of Sequence Sequence FSR cuts back to warm up
FSR cuts back to warm up value
At about 97% speed, 14HS speed relay picks up. At about 97% speed, 14HS speed relay picks up.
Inlet Guide vanes solenoid energizes (20TV) to open IGV’s to 57 deg Inlet Guide vanes solenoid energizes (20TV) to open IGV’s to 57 deg Compressor Bleed valves are closed
Compressor Bleed valves are closed
Generator Field Flashing relay (41FX) picks up. Generator Field Flashing relay (41FX) picks up.
On On Gas? Gas?
Enables Operator to transfer Enables Operator to transfer From one fuel to the other From one fuel to the other
Control system goes through complete sequence checks Control system goes through complete sequence checks
•
• Above operating speed (14HS)Above operating speed (14HS) •
• AC Lube oil pump is off AC Lube oil pump is off •
• DC lube oil pump is off DC lube oil pump is off •
• AC Hydraulic Pump is off AC Hydraulic Pump is off •
• Jaw clutch is disengagedJaw clutch is disengaged
Yes Yes
Energize Atomizing Air Energize Atomizing Air Bypass valve Solenoid Bypass valve Solenoid (20AA)
(20AA) Turbine Exhaust Frame cooling fans are started (88TK-1 and 2) Turbine Exhaust Frame cooling fans are started (88TK-1 and 2) Auxiliary Lube Oil Pump is stopped
Auxiliary Lube Oil Pump is stopped Auxiliary Hydraulic Pump is
Auxiliary Hydraulic Pump is stoppedstopped Turbine accelerates
Turbine accelerates
Turbine reaches acceleration set point (14HA) at approximately 50% speed Turbine reaches acceleration set point (14HA) at approximately 50% speed
Between 55 to 60% speed, diesel engine torque into turbine becomes low and the Between 55 to 60% speed, diesel engine torque into turbine becomes low and the aw clutch disengages as detected by the limit switch (33CS) and the diesel engine aw clutch disengages as detected by the limit switch (33CS) and the diesel engine cool down timer starts. Diesel engine accelerating solenoid de-energizes and the cool down timer starts. Diesel engine accelerating solenoid de-energizes and the diesel engine will idle until the cool down timer times out (5 minutes)
diesel engine will idle until the cool down timer times out (5 minutes) Turbine accelerates further
Is Generator Is Generator Synchronizing Synchronizing Selector in Selector in AUTO AUTO End of Sequence End of Sequence “Run Status” displayed
“Run Status” displayed
“Full Speed No Load” displayed “Full Speed No Load” displayed “ Start up Status” goes off “ Start up Status” goes off
“ Cranking” goes off “ Cranking” goes off
“ Synch Control” goes off “ Synch Control” goes off “Startup Control” displayed “Startup Control” displayed If Auto Synch permissives are OK, generator and lin are present an If Auto Synch permissives are OK, generator and lin are present an dabove the minimums, the control system will modultae FSR to bring dabove the minimums, the control system will modultae FSR to bring the speed TNH to 1
the speed TNH to 100.3% of the sta00.3% of the station linetion line frequencfrequency ande close they ande close the generator breaker when the phase angle is OK
generator breaker when the phase angle is OK
“Synh. Control” displayed “Synh. Control” displayed “Speed Control” goes off. “Speed Control” goes off. Synchronize Status” displayed Synchronize Status” displayed “ Full Speed No Load” goes off. “ Full Speed No Load” goes off. Synchronizing Control takes over to synchronize the unit
Synchronizing Control takes over to synchronize the unit
“Complete Sequence” displayed “Complete Sequence” displayed “Sequence in Progress” goes off “Sequence in Progress” goes off “Start Select” goes off
“Start Select” goes off
Enables manual raise / lower of the turbine speed reference TNR. Enables manual raise / lower of the turbine speed reference TNR. Closes compressor bleed valves (20CB), if not already closed Closes compressor bleed valves (20CB), if not already closed Note : Shuts of black start inverter on black start
“Loading” displayed “Loading” displayed
“Speed control” displayed “Speed control” displayed
“Pre-Selected” displayed “Pre-Selected” displayed “Loading” goes off
“Loading” goes off “ Cranking” goes off “ Cranking” goes off
Pre-selected Pre-selected load is load is selected? selected?
Turbine speed reference Turbine speed reference increase until the pre-selected increase until the pre-selected load is reached load is reached End of Sequence End of Sequence Base Base Select Select “ Spinning “ Spinning Reserve” Reserve” displayed displayed Turbine speed difference increases until
Turbine speed difference increases until temperature control limit is reached. temperature control limit is reached.
“ Loading” displayed “ Loading” displayed “Synchronizi
“Synchronizing” ng” goes goes off off
“
“ Temperature Temperature Control” Control” displayeddisplayed “Speed Control” goes off
“Speed Control” goes off “ Base Load” is displayed “ Base Load” is displayed
““ ””
End of Sequence End of Sequence
Unit goes to spinning Unit goes to spinning reserve ; end of sequence reserve ; end of sequence
Operator presses “ Stop” then “ Execute” Operator presses “ Stop” then “ Execute” LED comes steady ON
LED comes steady ON
“Stop Select” displayed “Stop Select” displayed “ Unloading” displayed “ Unloading” displayed “ Base Load” goes off “ Base Load” goes off
“Temperature Control” goes off “Temperature Control” goes off “ Sequence in Progress” displayed “ Sequence in Progress” displayed
Turbine Speed Reference TNR
Turbine Speed Reference TNR is is reduced at a reduced at a predetermined rate topredetermined rate to unload the unit
unload the unit
When the load is low enough to trip the reverse power relay, the When the load is low enough to trip the reverse power relay, the generator breaker opens
generator breaker opens
“ Unloading” goes off “ Unloading” goes off
“ Fired Shutdown” displayed “ Fired Shutdown” displayed
On On L Lii uuiidd
Turbine decelerates below the acceleration speed set point (14HA). Turbine decelerates below the acceleration speed set point (14HA). At about 20% speed shutdown command is given to close fuel valves At about 20% speed shutdown command is given to close fuel valves
Yes Yes Atomizing Air Atomizing Air bypass solenoid bypass solenoid de-energizes de-energizes FSR is reduced at a predetermined rate to reduce speed of turbine FSR is reduced at a predetermined rate to reduce speed of turbine Auxiliary Lube oil Pump is started when speed falls below 14HS Auxiliary Lube oil Pump is started when speed falls below 14HS Auxiliary Hydraulic pump is started when speed falls below 14HS Auxiliary Hydraulic pump is started when speed falls below 14HS Compressor bleed valves are open
Compressor bleed valves are open IFV is closed
IFV is closed
Normal Shutdown Normal Shutdown
On On L Lii uuiidd
Distillate Fuel forwarding pump shuts down Distillate Fuel forwarding pump shuts down
Liquid Fuel Stop valve solenoid is de-energized and stop valve Liquid Fuel Stop valve solenoid is de-energized and stop valve is closed
is closed
Liquid Fuel Pump Clutch is disengaged Liquid Fuel Pump Clutch is disengaged
Liquid Fuel Air Purge Solenoid Liquid Fuel Air Purge Solenoid de-energized (20PL)
de-energized (20PL)
End of Sequence End of Sequence
“Sequence in Progress” displayed “Sequence in Progress” displayed “ On Cool down” displayed
“ On Cool down” displayed Turbine coasts down to zero speed (14HR)
Turbine coasts down to zero speed (14HR)
Turbine Inlet air dirt separator fan motor (88TA) is stopped if used Turbine Inlet air dirt separator fan motor (88TA) is stopped if used Gas Fuel vent solenoid is deenergized (20VG)
Gas Fuel vent solenoid is deenergized (20VG) Starting clutch solenoid is energized (20CS) Starting clutch solenoid is energized (20CS) Jaw clutch engages
Jaw clutch engages H
H drdrauaulilicc raratctchehett ststarartsts
“Coasting Down” Displayed “Coasting Down” Displayed “ Stop Select” goes off “ Stop Select” goes off “ Speed Control” goes off “ Speed Control” goes off
No No