GAS TURBINE 7
Transcript of GAS TURBINE 7
GAS TURBINE
PROTECTIONS
Protection System
• Electrical Protection systems>>Over Speed>>High Exhaust Temperature>>Low Lube Oil Pressure>>Low Trip Oil Pressure>>High Lube Oil Temperature>>Loss of Flame>>High Vibration
Protection Systems Contd...>>Combustion Monitoring
>>Customer Trip
>>Fire Detection in Compartment Enclosures
>>Generator Class ‘A’ Trip
Over Temperature Alarm & TripOver Temperature Alarm & Trip
TTXM A A>BB
To Alarm Message & Speed Set Point Lower
A A>BB
A A>BB
OR
LATCHSET
RESET
TTKOT3
ToMaster
TTRX
TTKOT2
L86MR1 ProtectionAlarm &Trip
TTKOT1
Over Temperature Protection
TTXMTemp.Feedback
TRIP
Compressor Pressure Discharge
TTKOT3
TTKOT2
TRIP
ALARM
TTRX(Temp. ControlReference)
Vibration protection
• Standard Vibration Measurements used for Tripping GT are Velocity Type on Bearing Housing
• Alarm setting = 0.5 inches / sec
Trip setting = 1.0 inches / sec
• Total System is Tested for Integrity during Turbine Shut Down by Mark IV / V Panel
Vibration ProtectionIf All Gas Turbine Sensors
are Disabled or Faulty
If All Generator Sensors are are Disabled or Faulty
If 3 or more GT Sensors are Disabled or Faulty
If 2 or more Generator sensors Disabled or faulty
OR
OR
T
T
GROUPDISABLEDALARM &TRIP
STARTINHIBIT
Vibration TripOPTVTD
Any Trip and if any Adj.Pair Disabled or Alarmed
Any Trip and any Alarmfrom other Sensor
Any Trip and if 2 or moreSensors are Disabled
Any Trip and Any Alarmfrom another Sensor
Any Trip if 2 SensorInputs or Disabled
Adjacent Sensor
OR
OR
RESET
T
T
SETANDLATCH
RESET
SETANDLATCH
RESET
L39VGTT
Gas TurbineTrip
L39VGT
GeneratorTrip
Vibration Trip Contd..
L39VGTT
L39VGTOR
L39VT
HIGHVIBRATIONTRIP
BB 1
BB 2
A A > BB OR
T
LK39DIFF
OTHER SIMILARGROUPS
VibrationDifferentialAlarm
+_
Combustion Monitoring
• Exhaust Temperature Spreads are the Result of Uneven Combustion in all the Combustion Chambers
• Combustion Monitoring is Built in Mark IV/V
• Combustion Monitoring is Enabled after Machine Reaches FSNL
Exhaust Spread Calculations• Actual Spread
))TTXSP1 : Highest - Lowest TC
))TTXSP2 : Highest - 2 nd Lowest TC
))TTXSP3 : Highest - 3 rd Lowest TC
• Allowable Spread ( TTXSPL )
= 0.145 TTXC - 0.08 CTDA + 30 deg F
• During Dynamic Conditions the Allowable Spread is Increased
Trip Conditions•1. TTXSP1 > TTXSPL and
TTXSP2 > 0.8 TTXSPL and
The two Lowest TCs are adjacent
•2. TTXSP1 > 5 TTXSPL and
TTXSP2 > 0.8 TTXSPL and
The 2nd and 3rd Lowest TCs are Adjacent
•3. All Spreads are > TTXSPLTrip : Any of the above Conditions exists
for more than 9 Sec