Turbine Package Operators Manual
s
Chapter 1
Turbine Package System Overview
Engine Core Assembly ...................................................................................................................5
General Description...................................................................................................................................5
Air Inlet Casing...........................................................................................................................................5
Compressor Inlet Bearing Housing Assembly........................................................................................5
Compressor Stator Casings......................................................................................................................5
Center Casing and Bearing Housing Assembly......................................................................................6
Combustion System ..................................................................................................................................6
Compressor Turbine Outer Casing ..........................................................................................................6
Compressor Turbine Nozzle Assembly Stage 1 and Duct .....................................................................6
Turbine Rotor Assemblies ........................................................................................................................6
Power Turbine Outer Casing and Interduct Assembly ...........................................................................7
Power Turbine Bearing Housing ..............................................................................................................7
Exhaust Diffuser ........................................................................................................................................7
Auxiliary Gearbox ......................................................................................................................................7
Cooling and Sealing Air System...............................................................................................................7
Turbine Instrumentation............................................................................................................................8
Temperature Monitoring ........................................................................................................................................... 8
Speed monitoring ..................................................................................................................................................... 8
Vibration Monitoring ................................................................................................................................................. 8
Pressure Monitoring ................................................................................................................................................. 8
Turbine Core Auxiliary Equipment ...........................................................................................................9
Variable Guide Vane (VGV) Actuator....................................................................................................................... 9
Interstage Bleed Valve ............................................................................................................................................. 9
P2 Blow-off Valves ................................................................................................................................................... 9
Waterwash Nozzles.................................................................................................................................................. 9
Auxiliary Gearbox ....................................................................................................................................10
Lubricating Oil System .................................................................................................................11
General Description.................................................................................................................................11
Lubricating Oil Tank ............................................................................................................................................... 11
Lubricating Oil Pumps ............................................................................................................................................ 11
Temperature Control Valve .................................................................................................................................... 12
Pressure Control Valve .......................................................................................................................................... 12
Lubricating Oil Filters.............................................................................................................................................. 12
Oil Cooler Circuit .................................................................................................................................................... 12
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Oil Mist Eliminator .................................................................................................................................................. 12
Lubricating Oil Tank Breather System Flame Trap (if applicable).......................................................................... 12
Secondary Breather Flame Traps (if applicable).................................................................................................... 12
Instrumentation........................................................................................................................................12
Temperature Monitoring ......................................................................................................................................... 13
Pressure Monitoring ............................................................................................................................................... 13
Lubricating Oil Tank Level Monitoring .................................................................................................................... 13
Lubricating Oil System Requirements ...................................................................................................13
Fuel System ...................................................................................................................................15
General Description.................................................................................................................................15
Gas Fuel System Components ...............................................................................................................15
Off-Skid Block and Vent Valve ............................................................................................................................... 15
Demister or Filter/Coalescer (if applicable) ............................................................................................................ 16
Pipeline Trace Heating (if applicable)..................................................................................................................... 16
Fuel Strainer........................................................................................................................................................... 16
Block Valves........................................................................................................................................................... 16
Vent Valve .............................................................................................................................................................. 16
Fuel Control Valve/Actuator Assemblies ................................................................................................................ 16
Electronic Control Unit (ECU)................................................................................................................................. 17
Fuel Burners........................................................................................................................................................... 17
Igniter ..................................................................................................................................................................... 17
Instrumentation........................................................................................................................................17
Position Monitoring................................................................................................................................................. 17
Pressure Monitoring ............................................................................................................................................... 17
Temperature Monitoring ......................................................................................................................................... 18
Burner Instrumentation........................................................................................................................................... 18
Fuel System Requirements .....................................................................................................................18
Air Distribution System ................................................................................................................19
Air Distribution System Components ....................................................................................................19
Instrument Air Manual Shut-Off Valve and Filter Assembly ................................................................................... 19
Gas Fuel Module.................................................................................................................................................... 19
Off-Skid Gas Fuel Block and Vent Valve Assembly............................................................................................... 19
Lubricating Oil Module............................................................................................................................................ 19
P2 Blow-Off Valve Air Manifold .............................................................................................................................. 20
Engine Auxiliary Module......................................................................................................................................... 20
Combustion Air Filter System................................................................................................................................. 20
Ignition System .............................................................................................................................21
Introduction ..............................................................................................................................................21
General Description.................................................................................................................................21
High Energy Spark Generator.................................................................................................................21
Starting System.............................................................................................................................23
General Description.................................................................................................................................23
AC Electric Drive Motor.......................................................................................................................................... 23
Hydraulic Pump Assembly ..................................................................................................................................... 23
Hydraulic Motor Assembly...................................................................................................................................... 23
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Hydraulic Pump Boost Flow Oil Filter..................................................................................................................... 24
Starter Clutch ......................................................................................................................................................... 24
Turbine Underbase, Enclosure and Air Supply/Exhaust Systems............................................25
Introduction ..............................................................................................................................................25
Underbase ................................................................................................................................................25
Turbine Acoustic Enclosure ...................................................................................................................25
Ventilation System...................................................................................................................................25
Dampers................................................................................................................................................................. 26
Ventilation Inlet and Outlet Silencers ..................................................................................................................... 26
Ventilation Inlet Filter – Inertial Type (if applicable)................................................................................................ 26
Ventilation Inlet Filter – Marine Type (if applicable) ............................................................................................... 26
Negative Pressure Ventilation Fan(s) (if applicable) .............................................................................................. 26
Positive Pressure Ventilation Fan(s) (if applicable)................................................................................................ 26
Instrumentation....................................................................................................................................................... 26
Combustion Air System ..........................................................................................................................27
Air Inlet Filter - Marine Type (if applicable)............................................................................................................ 27
Air Intake Filter - Pulse Type (if applicable)............................................................................................................ 27
Air Intake Silencer .................................................................................................................................................. 27
Acoustic Lagging.................................................................................................................................................... 28
Instrumentation....................................................................................................................................................... 28
Exhaust System .......................................................................................................................................28
Exhaust Silencer .................................................................................................................................................... 28
Acoustic and Thermal Lagging............................................................................................................................... 28
Instrumentation....................................................................................................................................................... 28
Fire & Gas Protection System......................................................................................................29
General Description.................................................................................................................................29
System Control and Operation ...............................................................................................................29
System Components ...............................................................................................................................29
Heat Detectors ....................................................................................................................................................... 29
Infra Red (IR) Flame Detectors .............................................................................................................................. 30
Gas Detectors ........................................................................................................................................................ 30
Ventilation Dampers............................................................................................................................................... 31
Extinguishant Bottles.............................................................................................................................................. 31
Instrumentation........................................................................................................................................31
Pressure Monitoring ............................................................................................................................................... 31
Position Monitoring................................................................................................................................................. 32
Gearbox and Generator ................................................................................................................33
Gearbox ....................................................................................................................................................33
Generator..................................................................................................................................................33
Cooling System ...................................................................................................................................................... 33
Generator Bearing Lubrication ............................................................................................................................... 33
Vibration Monitoring ............................................................................................................................................... 34
Generator Winding Temperature Monitoring.......................................................................................................... 34
Anti-condensation Heating ..................................................................................................................................... 34
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Electrical Operation .................................................................................................................................34
Generator Control System ......................................................................................................................34
General Description................................................................................................................................................ 34
Operation................................................................................................................................................................ 34
Control Panels and Electrical Equipment Cabinets ...................................................................35
Introduction ..............................................................................................................................................35
Unit Control System ................................................................................................................................35
General Description................................................................................................................................................ 36
Human / Machine Interface (HMI) .......................................................................................................................... 36
Generator Monitoring & Control ............................................................................................................................. 37
Generator Control Panel (GCP) ..............................................................................................................37
Description ............................................................................................................................................................. 37
Batteries & Battery Charging System ....................................................................................................38
Battery Charger & System Controller ..................................................................................................................... 38
24 Volt Batteries..................................................................................................................................................... 38
24 Volt DC Battery Charger.................................................................................................................................... 38
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Engine Core Assembly
The SGT-400 is a twin shaft, simple open cycle; non-regenerative industrial gas turbine designed
for both power generation and mechanical drive applications. The core engine consists of a
radial inlet casing through which air enters the eleven stage axial compressor for compression
prior to entry to the combustion system.
General Description
The combustion system employs reverse flow combustion chambers to mix, burn and expand the
air fuel mixture to drive the twin shaft turbine and exit through the exhaust diffuser.
The integrated compressor and compressor turbine assembly, and separate power turbine rotor
assembly, are supported and located by journal and thrust bearings in the inlet, compressor
turbine and power turbine bearing housings respectively.
An auxiliary gearbox provides ancillary drives for the main lubricating oil pump, the liquid fuel
pump (if fitted), and to provide drive to the turbine from the starting system.
Refer to the SECTIONAL ARRANGEMENT – SGT-400 (MW-1-1) located in this Manual
Volume.
Air Inlet Casing
The Air Inlet Casing is secured to the Inlet Bearing Housing both designed and shaped to provide
a smooth path for the incoming air to the compressor. An inlet screen and a flexible joint, which
accommodates relative movements due to thermal expansion, are fitted to the rectangular casing
entry point to which external ducting is connected.
Compressor Inlet Bearing Housing Assembly
The Compressor Inlet Bearing Housing Assembly, which is mounted on the turbine/auxiliary
gearbox support casing, provides support for the Air Inlet Casing and Low Pressure (LP)
Compressor Stator casing. Provision is made, at the bottom of the casing, for the attachment of
the front gas generator support assembly. A tilting pad journal and thrust bearing assembly
within the housing supports and locates the inlet end of the gas generator rotor.
Compressor Stator Casings
The Compressor Stator Casings consist of an LP Compressor Stator casing and a High Pressure
(HP) Compressor Stator casing.
The LP Compressor Stator casing is split along its centerline, bolted at its forward face to the
Compressor Inlet Bearing Housing assembly, and has a spigot bolted to the center casing at the
rear end. Boroscope access holes are provided in the top half casing to enable examination of
the compressor stator and rotor blades.
Variable geometry inlet guide vanes form the first row of stator vanes, with the subsequent four
rows being variable geometry compressor stator blades, which assist starting and prevention of
compressor surge. An externally mounted operating mechanism controls the movement of the
vanes. The remaining LP stator blades are retained by dovetail grooves in the casing.
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The HP compressor stator casing is in the form of an insert split along its horizontal centerline
and located in the pressure casing back plate. The HP compressor stator blades being retained by
dovetail grooves in the insert.
Center Casing and Bearing Housing Assembly
The Center Casing and Bearing Housing Assembly provide support for the hot end of the gas
generator assembly, including the combustion system and the Compressor Turbine (CT) Outer
Casing. A tilting pad journal bearing provides support for the exit end of the gas generator rotor.
Combustion System
The Combustion System comprises six tubular combustion chambers symmetrically positioned on
the forward face of the Center Casing and Bearing Housing Assembly.
The system is of axial reverse flow design; air leaving the compressor exit nozzle is reversed and
enters the head of the combustion chambers via a swirler plate, which imparts a rapid swirling
motion to the flow to ensure complete mixing of fuel and air.
Compressor Turbine Outer Casing
The CT Outer Casing provides the interface between the Center Casing and Bearing Housing
Assembly and the Power Turbine (PT) Outer Casing and Interduct Assembly. Provisions are
made, at the bottom of the casing, for the attachment of the rear gas generator support
assemblies. Boroscope access holes are provided in the top of the casing to enable examination
of the CT stator and rotor blades.
Compressor Turbine Nozzle Assembly Stage 1 and Duct
Within the Compressor Turbine Nozzle Assembly Stage 1 and Duct are housed the CT1 nozzle
segments, the combustion chamber transition ducts and the CT 2 nozzle assembly. Also, with the
CT2 nozzle segments is the CT 2 retaining shroud, which carries a seal ring between the CT
Nozzle Assembly Stage 1 and Duct and the PT Outer Casing and Interduct Assembly.
Turbine Rotor Assemblies
The turbine rotor assemblies are comprised of two separate assemblies, the CT Rotor Assembly,
and the PT Rotor Assembly.
The Compressor Rotor is a single spool 11 stage axial design made up of a series of discs
carrying dovetail rooted compressor blades, located together with Hirth couplings at the outside
diameter and held together with a single central tension stud bolt. Overhung from the
Compressor rotor and secured to it with a central tension stud bolt is the CT, which is of a twostage design. It consists of two rotor discs located on the Compressor spool by means of a
central tension stud and Hirth couplings and carrying fir tree rooted turbine blades.
The Power Turbine is of two-stage axial design, consisting of two-rotor disc located with Hirth
couplings and carrying fir tree rooted turbine blades. The PT rotor is bolted to a solid output
shaft by means of a tension bolt.
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Power Turbine Outer Casing and Interduct Assembly
The Power Turbine Outer Casing and Interduct Assembly are attached to the CT Center Casing
and Bearing Housing and the Spoke Frame Assembly. It provides the mounting for the PT1
Stator assemblies with the Exhaust Diffuser bolted to the Spoke Frame Assembly/PT Support
Assembly.
Power Turbine Bearing Housing
The exhaust diffuser and support assembly from the outer casing rigidly support the Power
Turbine Bearing Housing. The power turbine exit rotor shaft is supported in two tilting pad
journal bearings and provided with main and reverse thrust bearings.
Exhaust Diffuser
The lagged Exhaust Diffuser, mounted from the turbine pressure casing provides diffusion of the
exhaust gases for the exhaust ducting system.
Auxiliary Gearbox
The auxiliary Gearbox is mounted via an adapter ring directly off the gas generator inlet bearing
housing and driven from the gas generator shaft. It contains the necessary auxiliary drives for
the hydraulic starter motor and its associated clutch, and the main lubricating oil pump.
Cooling and Sealing Air System
Compressor air is used for sealing at labyrinth seals and cooling of high temperature
components. Refer to the COOLING AND SEALING AIR SYSTEM DIAGRAM – SGT-400
(MW-2-1) located in this Manual Volume. Medium pressure air, taken from the bleed band at
the seventh stage of the compressor, is used to:
•
•
Pressurize the inlet labyrinth seal.
•
Pressurize the labyrinth seals of the PT and cool the turbine discs.
Pressurize the labyrinth seals located either side of the compressor turbine journal
bearing to prevent stage ten high-pressure air entering the bearing housing.
Stage ten high-pressure bleed air taken from before the compressor exit guide vane is used to:
•
Balance the medium pressure air used to pressurize the labyrinth seals at the compressor
journal bearing.
•
Cool the turbine rotor discs and the interstage diaphragm.
Compressor exit air is used to:
•
Cool the CT1 and CT2 nozzle assemblies via holes in the nozzle inner and outer carrier
rings into the cooling tube of each nozzle followed by discharge into the gas stream by
trailing edge slots.
•
Cool the CT1 and CT2 rotor blades via their triple pass convection system prior to being
ejected into the gas stream.
Used medium pressure air is vented to atmosphere through the secondary breather system.
Used stage ten high-pressure air is vented into the exhaust system through the primary breather
system.
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Turbine Instrumentation
Instrumentation is provided to monitor the turbine parameters and provide warning and trip
control functions.
Refer to the Turbine Instrumentation schematic diagram located in this Manual Volume.
Temperature Monitoring
Temperature detectors (RTD1 and RTD48) mounted in the air inlet casing, and thermocouples
(TC1 to TC13 inclusive), mounted in the gas generator exhaust outlet, monitor compressor
turbine operating temperature and temperature deviation. Additionally the output thermocouples
monitor combustion condition and will shut the turbine down in the event of flame out in one of
the combustion chambers. A further two thermocouples (TC101 and TC102) are mounted in the
exhaust ducting, downstream of the exhaust diffuser, as part of the turbine gas path
instrumentation for turbine control.
Thermocouples (TC17 and TC18), mounted in the Center Casing and Bearing Housing Assembly,
measure the compressor exit temperature.
Thermocouples (TC21 to TC28, and TC91, TC92, TC96 and TC227) positioned in the appropriate
bearings, measure journal and thrust bearing temperatures.
Speed monitoring
Speed probes (SD20 to SD23) are used for speed detection and overspeed protection in the gas
generator, and speed probes (SD24 to SD27) are used for speed control indication and
overspeed protection in the power turbine. Probes monitor from the gas generator rotor shaft
and power turbine rotor shaft.
Vibration Monitoring
X-Y non–contacting vibration probes (UD10X1 UD10Y1, UD11X1, UD11Y1, UD12X1, UD12Y1 and
UD13X1 UD13Y1) are provided adjacent to each rotor journal bearings, within the gas generator
and power turbine, to monitor radial vibration. Probes (UD10X2 UD10Y2, UD11X2 UD11Y2,
UD12X2 UD12Y2, UD13X2 and UD13Y2) are fitted as non–active spares.
Axial vibration detection probes (ZD10T1 and ZD10T2) are provided at the gas generator input
end thrust bearings.
Keyphasors (ND10K1 and ND12K1) are provided at the gas generator input end bearing and
power turbine output end bearing respectively, (ND10K2 and ND12K2) are fitted as non-active
spares.
Pressure Monitoring
Pressure transmitters are provided to facilitate engine control as follows:
•
Air inlet pressure (PT7).
•
Turbine compressor discharge pressure (PT8).
•
Interduct static pressure (PT258).
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Turbine Core Auxiliary Equipment
Variable Guide Vane (VGV) Actuator
The purpose of the variable guide vane (VGV) system is to vary the flow through the gas
generator to optimize starting and running conditions. This is achieved by altering the angles at
which the inlet guide vanes and the first three stages of compressor blades are presented to the
airflow. The position of the blades is altered by the operation of the mechanically linked VGV
actuator.
The electrical VGV actuator (ZZ8) consists of an actuator and servo positioner assembly. The
assembly is mounted on the turbine to vary the position of the inlet guide vanes and the first,
second, third and fourth stages of compressor stator blades.
The actuator position is controlled by the servo positioner, which reacts to drive signals (ZC4)
from the unit control panel. The unit control panel monitors the position of the VGS blades/inlet
guide vanes using a proportional feedback signal (ZT9) from the VGS actuator.
Interstage Bleed Valve
To prevent gas generator surge during starting, it is necessary to reduce the compressor delivery
air pressure. This is achieved by the use of the interstage bleed valve, mounted on the upper
low-pressure compressor stator casing.
During the turbine starting sequence, as the compressor speed increases, control air is bled from
the delivery stage of the compressor and routed through a pilot valve (XV60) onto the piston of
the interstage bleed valve (XV59). As the air pressure increases, the piston is pushed to its full
extent of travel, thus closing off the air being vented to atmosphere.
Operation of the pilot valve is achieved by instrument air controlled by a solenoid mounted in the
instrument air pipeline.
P2 Blow-off Valves
Blow-off valves (XV267 and XV268) are mounted on the port and starboard sides of the turbine
to modulate engine compressor air during starting and to enable a rapid discharge of air during
engine over-speed conditions.
This is achieved by bypassing engine air from upstream of the power turbine through the blowoff valves into the exhaust diffuser.
The blow-off valves are operated by solenoid valves (port - SOL625, SOL627 and starboard SOL626, SOL628). The solenoids direct P2 air to either side of the valve actuators (XV267 and
XV268). The solenoid valves are operated by a drive signal (ZC43, ZC44) from the unit control
panel. The unit control panel monitors the position of the P2 blow-off valves using a proportional
feedback signal (ZT141, ZT142) from the P2 blow-off valve butterfly spindles.
Waterwash Nozzles
Waterwash nozzles are mounted in the engine air inlet to facilitate the supply of wash and rinse
fluids into the turbine during engine hot and cold wash operations. A last chance filter (XF27)
ensures filtration of the wash/rinse fluids.
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Auxiliary Gearbox
The auxiliary gearbox is mounted via an adaptor ring directly off the gas generator inlet bearing
housing and driven from the gas generator shaft. It contains the necessary auxiliary drives for
the hydraulic starter motor and its associated clutch, and the main lubricating oil pump.
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Lubricating Oil System
Mineral lubricating oil is used to lubricate and cool the turbine journal and thrust bearings, the
generator bearings and the gearbox bearings, gears and splines. The oil is also used as a
hydraulic oil to operate the hydraulic starting system when starting the turbine.
General Description
The oil is delivered from an on-skid lubricating oil tank and circulated throughout the lubricating
system under normal running conditions by a main oil pump. The system includes a temperature
control valve, pressure control valve, filter, instrumentation and associated piping to provide the
correct delivery conditions.
The used oil is returned to the tank by gravity drainage to create a continuously circulating
system.
Heat is removed from the oil by an oil cooler circuit, which is controlled by the temperature
control valve.
A lubricating oil tank breather system is provided to vent to atmosphere oil fumes that are
generated whilst the turbine is running.
A schematic diagram of the lubricating oil system is located in this Manual Volume.
Lubricating Oil Tank
The lubricating oil tank is integrated into the underbase fabrication and is provided with internal
baffles to aid circulation and maximize removal of entrapped air. Covers are provided to facilitate
cleaning of the interior if contamination occurs.
The tank is fitted with immersion heater(s) to maintain the correct pre-start oil temperature.
Integral thermal protection is provided.
Flip lid filler point(s) with integral strainers are provided for filling and replenishment.
Level gauge(s) provide visual indication of the oil level within the oil tank.
Lubricating Oil Pumps
Three lubricating oil pumps are provided:
•
The main pump (XP1) which is mounted on, and driven by the auxiliary gearbox,
provides lubrication during normal running.
•
The auxiliary pump (XP2), which is submerged in the lubricating oil tank and driven by an
AC motor, provides lubrication during turbine start, run up and post shutdown.
•
The emergency pump (XP3) which is submerged in the lubricating oil tank and driven by
a DC motor, provides essential lubrication to the turbine hot bearing in the event of the
auxiliary pump or AC power failure, during or after shutdown.
Circulation between the three pumps is controlled by non-return valves, located in each pump
delivery system.
Each pump is provided with a pressure relief valve to guard against over-pressurization.
A strainer is provided at each pump suction inlet.
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Temperature Control Valve
A temperature control valve (XV428) operates at a set value to divert lubricating oil through the
oil cooler (TH1) as necessary to maintain the temperature of the oil at the optimum level.
Pressure Control Valve
Pressure control valve (PCV1) maintains a constant oil pressure to the bearings during turbine
running. The excess oil is spilled back through the valve to the lubricating oil tank.
Lubricating Oil Filters
Two filters are provided:
•
The main filter(s) (XF2 and XF3), which are installed downstream of the pressure control
valve, filters the main line flow of lubricating oil from the main and auxiliary pumps.
•
The lubricating oil flow from the DC motor driven emergency pump, which is separate
from the main line flow, is filtered by an emergency filter (XF4).
Oil Cooler Circuit
An oil cooler circuit incorporating an air blast oil cooler (TH1) is used to dissipate heat from the
lubricating oil prior to its entry into the main supply line. Flow to the cooler circuit is controlled
by the temperature control valve (XV428).
Non-return valves (XV26 and XV27) are fitted in the supply and return lines to prevent the
lubricating oil draining back to the tank when the turbine is shutdown.
Oil Mist Eliminator
An oil mist eliminator (XF7) is provided in the lubricating oil tank breather system to reduce the
amount of oil mist being exhausted to atmosphere.
Lubricating Oil Tank Breather System Flame Trap (if applicable)
The breather system contains a flame trap to prevent the ignition of any oil mist, which may
cause a subsequent explosion in the lubricating oil tank.
Secondary Breather Flame Traps (if applicable)
Flame traps are fitted in the compressor turbine and power turbine secondary breather systems
to prevent the ignition of any oil mist which may cause a subsequent explosion in the breather
passages.
Instrumentation
Instrumentation is provided to monitor the lubricating oil system parameters, provide warning
and trip control functions.
Refer to the Lubricating Oil System schematic diagram located in this Manual Volume.
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Temperature Monitoring
A resistance temperature detector (TT7) mounted in the lubricating oil supply tank monitors the
tank oil temperature and provides a permissive signal for tank immersion heater(s) control. The
information is also used to inhibit a start until the tank oil temperature is above a set value.
The temperature of the lubricating oil is measured by instrumentation mounted in the manifold
block by resistance temperature detectors (TT66A and TT66B) provide high oil temperature
warning and shutdown.
Pressure Monitoring
A pressure transmitters (PT6A, PT6B and PT6C (if fitted)) are mounted in the compressor
turbine supply line to provide lubricating oil pressure low/high warning and emergency lubricating
oil pump control signals.
The pressure drop across the main lubricating oil filter assembly is monitored by a pressure
differential transmitter (PDT8) to provide a warning of deteriorating element condition.
Each main lubricating oil filter housing (XF2, XF3) and the emergency oil filter housing (XF4) is
fitted with a pop up indicator button to provide a visual indication of filter blockage.
Lubricating Oil Tank Level Monitoring
A level transmitter (LT1) is used to monitor the level of the oil in the lubricating oil tank. The
information provided is used to inhibit starts if the oil level is below a set value during the gas
turbine starting process and to annunciate a warning or shutdown if the oil level falls below a set
value during normal gas turbine operation.
The level switch is also used to inhibit the operation of the immersion heater(s) if the level of the
oil in the tank is below a pre-determined level.
Lubricating Oil System Requirements
In normal conditions, the turbine is designed to run on mineral oil to ISO/VG46 in accordance
with company Fluids Specification 65/0027, which is located in this Manual Volume. Where, due
to prevailing ambient conditions or driven machinery requirements, it is necessary to use a
heavier or lighter viscosity grade of oil, ISO/VG68 or ISO/VG32 may be used respectively.
However, the company must be consulted before the use of these alternative oils.
a
Caution: It is important to use the correct type of lubricating oil. The use of oil
with insufficient or incorrect additives will cause oil performance to deteriorate.
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Fuel System
The fuel system is designed to deliver fuel to the combustion system at the correct pressure and
flow required for the applicable power demand.
General Description
The schematic diagrams of the Fuel System can be found in this Manual Volume.
The fuel system comprises:
Off-skid Components
•
block and vent valve assembly (XV30, XV31)
•
demister (if applicable)
•
filter/coalescer (if applicable)
On-skid components
•
gas fuel supply strainer (XF94)
•
two block valves (XV6, XV7)
•
vent valve (XV212)
•
main fuel control valve/actuator assembly (XV150, XM26)
•
pilot fuel control valve/actuator assembly (XV149, XM27)
•
electronic control unit
•
system monitoring and control instrumentation
•
pipeline trace heating (if applicable).
Gas Fuel System Components
Off-Skid Block and Vent Valve
The block and vent valve assembly is located in the customers gas supply line. The assembly
comprises of a block valve (XV30) and a vent valve (XV31). Both valves are controlled by
pneumatically operated rotary actuators. Air is directed to the actuators by solenoid valves
(SOL12 and SOL11) respectively. When the situation demands, the block valve closes to prevent
gas entering the on-skid fuel system and the vent valve opens to vent the interconnecting
pipework.
The block valve is spring loaded to fail in the ‘closed’ position. The vent valve is spring loaded to
fail in the ‘open’ position.
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Demister or Filter/Coalescer (if applicable)
The off-skid demister or filter/coalescer is used to remove liquids and particulates from the gas
fuel.
The gas enters the filter/colaescer at the inlet pipe and passes through a special filter element
into the top chamber, from where it leaves the filter/colaescer in a clean dry condition via the
outlet pipe.
Pipeline Trace Heating (if applicable)
The gas fuel pipelines are trace heated to prevent the formation of condensation in the gas
system.
Fuel Strainer
A 76-micron fuel strainer (XF94) is located in the fuel pipework downstream of the skid edge to
protect the burner orifices from blockage and contamination.
Block Valves
The primary (XV7) and secondary (XV6) block valves provide isolation of the on–skid fuel system
from the gas supply. They are controlled by integral actuators, which are operated by instrument
air and spring pressure. The instrument air supply to the actuators is controlled by pilot solenoids
(SOL5 and SOL110).
The block valves are designed to fail in the closed position.
Vent Valve
The vent valve (XV212) provides for venting of the gas fuel pipework between the two block
valves on turbine shutdown. The valve is controlled by an integral actuator operated by
instrument air and spring pressure. The instrument air supply to the actuator is controlled by a
pilot solenoid (SOL470).
The vent valve is designed to fail in the open position.
Fuel Control Valve/Actuator Assemblies
The main and pilot fuel control valves (XV150 and XV149) are of the rotary ball valve type and
operated through a zero backlash coupling by electrically operated rotary actuators (XM26 and
XM27). Each valve/actuator assembly is firmly mounted and connected into the fuel system. The
valves are calibrated and set up to meter the fuel flow to the burners under the control of an
electronic control unit. Integral position transmitters (ZT12 and ZT103) monitor the position of
the control valve actuators.
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Electronic Control Unit (ECU)
The ECU is an integral part of the fuel system and interfaces with the fuel control valve actuator
and the turbine governor to provide accurate fuel control, utilizing a high-speed microprocessor
at its heart.
The ECU constantly receives fuel condition input signals, and uses this information to calculate
the correct position of the fuel valve according to the flow rates demanded by the turbine
governor. The ECU also provides feedback of valve position and fault conditions to the turbine
control system.
Fuel Burners
The burners incorporate main and pilot gas ports to introduce the correct proportion of fuel for
the combustion process during starting and turbine operation.
Igniter
An igniter (IG1 to IG6) is incorporated in each burner to provide a heat source to the fuel during
engine starting. The units are connected by high-tension leads to a high-energy spark generator.
Instrumentation
Instrumentation is provided to monitor the fuel system parameters and provide warning and
protective control functions if unsafe or damaging conditions are detected.
Position Monitoring
Position switches (ZS12 and ZS45) monitors the open/closed position of the off-skid block valve
and switches (ZS44 and ZS11) monitor the open/closed position of the off-skid vent valve.
Position switches (ZS178 and ZS5) monitor the open/closed position of the primary on-skid block
valve, switches (ZS207 and ZS208) monitor the open/closed position of the secondary on-skid
block valve and switches (ZS742 and ZS743) monitor the open/closed position of the vent valve.
The switches initiate a start inhibit signal if the any of the valves are wrongly positioned prior to
start.
Pressure Monitoring
Pressure transmitters (PT2 and PT181) monitor the gas supply pressure at the input and the
demand pressure at the output of the main gas fuel control valve respectively. The pressure
differential across the valve is used in conjunction with the valve feedback position to calculate
the approximate percentage fuel flow through the valve.
Pressure transmitters (PT220 and PT182) monitor the gas supply pressure at the input and the
demand pressure at the output of the pilot gas fuel control valve respectively. The pressure
differential across the valve is used in conjunction with the valve feedback position to calculate
the approximate percentage fuel flow through the valve.
Dynamic air pressure through the center casing is monitored by a pressure transmitter (PT200).
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Temperature Monitoring
A temperature transmitter (TT6) monitors the gas fuel supply temperature upstream of the gas
fuel control valve(s). The transmitter relays temperature information to the ECU and
programmable controller and provides low and high temperature shutdown signals.
Burner Instrumentation
Six temperature sensors (TC255–TC260) mounted in each of the burner assemblies continuously
monitor burner operation and provide operational data to the turbine control system.
Fuel System Requirements
Refer to the SIEMENS Fluids Specification 65/0027, which is located in this Manual Volume,
for more specific information on fuel requirements.
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Air Distribution System
Instrument air is supplied to the package to assist in the operation and control of the gas fuel
module valves, the off-skid gas fuel block and vent valves, the lubricating oil module valves, the
P2 blow-off valves during starting and stopping, the interstage bleed valve, the combustion air
filter pulse cleaning system, the enclosure vent dampers, the auto drain system and the turbine
seals. P2 air from the turbine core is used to operate and control the P2 blow-off valves during
normal turbine operation.
The air distribution system delivers the air through a system of pipework and manifolds to the
various components.
Refer to the SIEMENS Fluid Specification 65/0027, which is located in this Manual Volume,
for specific information on the instrument air quality requirements.
Instrumentation
The pressure transmitter (PT185) monitors the instrument air supply pressure. The pressure
transmitter initiates high and low pressure warning and shutdown signals.
Air Distribution System Components
Instrument Air Manual Shut-Off Valve and Filter Assembly
A manual shut-off valve (HV220) and filter (XF102) assembly is located in the instrument air
supply pipework. The shut-off valve facilitates manually isolation of the system for maintenance
purposes. The filter provides filtration of the instrument air supply to remove particles above
5 microns.
Gas Fuel Module
Instrument air is supplied to the gas fuel module to provide actuation for the primary and
secondary block valves (XV7, XV6), and for the vent valve (XV212). The air is directed by the
valve solenoids (SOL5, SOL110, SOL470) to the actuators, which position the valves as required
for engine operation.
Off-Skid Gas Fuel Block and Vent Valve Assembly
Instrument air is supplied to the block valve (XV30) solenoid (SOL12) and the vent valve (XV31)
solenoid (SOL11) of the off-skid gas fuel block and vent valve. The air is directed by the
solenoids to actuators, which position the valves as required for engine operation.
Lubricating Oil Module
Instrument air is supplied to the lubricating oil module to provide control air for the lubricating oil
supply pressure control valve (PCV1) and the temperature control valve (XV428) position
indication.
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P2 Blow-Off Valve Air Manifold
Instrument air is supplied to the P2 blow-off valves via the air manifold during engine start and
shutdown. The P2 blow-off valve system is protected from excessive pressure by a pressure relief
valve (PSV159).
P2 air for the P2 blow-off valves is supplied from the engine through a filter (XV187) and
pressure control valve (PCV150) during normal engine operation.
A non-return valve (XV430) prevents P2 air from entering the main instrument air system during
normal engine operation.
Engine Auxiliary Module
Instrument air is supplied via process airlines to the engine auxiliary module for pressurization of
the engine seals and to the instrument air manifold.
Combustion Air Filter System
Instrument air is supplied as required to the combustion air filter for operation of the pulse clean
system (if applicable).
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Ignition System
Introduction
During the start up cycle, a high-energy pulse spark from the ignition system is used to ignite the
combustion chamber air/fuel mixture.
General Description
The ignition system consists of a high-energy spark generator mounted in the underbase, with
each combustor flame tube having its own igniter assembly (IG1 to IG6), which is permanently
fixed. The units are connected with high-tension leads enclosed in an armored conduit.
High Energy Spark Generator
The high-energy spark generator is a capacitor discharge system encapsulated within a steel
enclosure with appropriate supply and high-tension terminations.
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Starting System
The turbine is started with a hydraulic transmission system driving through an overrunning clutch
assembly on the auxiliary gearbox. The turbine rotor is accelerated to a speed at which fuel may
be introduced into the combustion system and ignited to provide self-sustained acceleration, up
to the normal operating speed.
General Description
The hydraulic start system comprises of an AC motor driven hydrostatic pump and boost pump
mounted on the turbine underbase to drive the gearbox mounted hydrostatic starter motor. The
hydraulic starter motor connects through a high-speed overrunning clutch and associated gearing
in the gearbox to the turbine rotor assembly.
The pump and motor displacements are controlled to provide the correct system acceleration.
On achieving a successful turbine start and at a pre-set speed, power to the AC motor is
removed and the system deactivated.
Turbine lubricating oil is used for the closed loop hydraulic circuit. Make-up oil is drawn from the
lubricating oil tank to provide cooling.
During the hydraulic starter motor run up, the position of the variable geometry inlet guide vanes
and stator blades are adjusted by the variable geometry stator actuator to optimize aerodynamic
conditions for the starting cycle.
Prior to ignition, the turbine compressor interstage bleed valve is used to bleed compressor air to
atmosphere to reduce the start-up power requirements and prevent compressor surge.
The Schematic Diagram of the Starting System is located in this Manual Volume.
AC Electric Drive Motor
The AC electric drive motor (XM3) for the start system is an induction motor with anticondensation heaters and thermistors for monitoring the motor winding temperatures. The
thermistors relay temperature information to the programmable controller and provide start
inhibit, and high temperature warning and shutdown signals.
Hydraulic Pump Assembly
The hydraulic pump assembly (XP5, XP9) is a variable displacement, axial piston type with preset pressure cut-off control. The varying current signal from the unit control panel adjusts the
pump displacement to achieve the required control rate.
Hydraulic Motor Assembly
The variable displacement hydraulic starter motor (XM91) is fitted with a pre-set high-pressure
related volume control. This control will decrease the motor displacement thereby increasing
turbine speed as the motor differential pressure reduces.
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Hydraulic Pump Boost Flow Oil Filter
A high-pressure filter (XF14) and bypass valve assembly (XV185) filters the oil to the hydraulic
pump. The filter housing is fitted with a pop up indicator button to provide a visual indication of
filter blockage.
Starter Clutch
The hydraulic motor is mounted to the auxiliary gearbox through a high-speed overrunning
clutch. During start up, the motor/clutch has a positively engaged connection to the auxiliary
gearbox. The hydraulic motor runs the turbine up to its ignition speed. Upon ignition, the turbine
speed increases further which causes the clutch to disengage. The design of the starter clutch
enables re-engagement on run down, without having to fully stop the turbine before attempting
a restart.
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Turbine Underbase, Enclosure and Air Supply/Exhaust
Systems
Introduction
The underbase forms a structure for mounting the turbine, auxiliary gearbox and associated
systems.
An acoustic enclosure is provided over the turbine, interfacing with the underbase, to reduce
noise levels from the machinery to an acceptable level.
A ventilation system is used to purge the turbine enclosure prior to a start, to cool the turbine
during running and for a period following shutdown, and to ventilate the enclosure should a gas
leak occur. The ventilation air is discharged from the enclosure through the ventilation outlet.
The intake system filters and ducts combustion air to the turbine inlet casing and incorporates a
silencer to reduce noise emissions from the turbine intake.
The exhaust system ducts the exhaust gases from the turbine to atmosphere and incorporates a
silencer to reduce noise emissions
A schematic diagram of the ventilation and combustion air systems is located in this Manual
Volume.
Underbase
A single piece underbase of fabricated steel construction, which incorporates an integral
lubricating oil tank, provides mounting points for the main turbine/gearbox support and the
turbine combustion casing support. Torque reactions from the turbine/gearbox are transmitted
from the fabrication to the foundations through the multiple mounting pads and foundation
bolting.
The underbase incorporates mounting features/points for all the turbine support systems. System
supply, vent, and drain connections are integrated into the main side members of the fabrication.
The underbase also incorporates integral plating on the underside of the fabrication, which forms
a spillage collection feature for any system leakage.
Turbine Acoustic Enclosure
The turbine acoustic enclosure comprises a load bearing framework, with removable paneling
and hinged doors, mounted on the turbine underbase. Sound attenuation is achieved by a
combination of material thickness, acoustic infill and, if required, the provision of an acoustic
skirt.
Ventilation System
The ventilation system draws air from the atmosphere and directs it through ducting and system
components before discharging it back to atmosphere in a safe area.
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Dampers
Control system activated dampers are located at the enclosure ventilation inlet and outlet
openings, which close when a fire is detected to retain the fire extinguishant. The dampers are
also closed when the unit is in standby mode.
Ventilation Inlet and Outlet Silencers
Silencers are provided to reduce noise emissions through the ventilation ducting from the gas
turbine and the ventilation fan(s).
Ventilation Inlet Filter – Inertial Type (if applicable)
An inertial type ventilation filter (XF33) is provided at the inlet to the ventilation system.
An AC driven bleed fan (XM42) is used to remove contaminants from the inertial panels.
Ventilation Inlet Filter – Marine Type (if applicable)
A multi stage marine type ventilation filter (XF33) is provided at the inlet to the ventilation
system.
The first stage of the filter consists of an optional selection of either; a weather louver, vane
separator, vane separator with hood or a weather hood and bird screen, dependant upon the
specific site conditions.
The main filter section comprises of a coalescer filter panel.
The final stage consists of a vane separator.
Negative Pressure Ventilation Fan(s) (if applicable)
Motor driven fan(s) (XM6 and if applicable XM7) are mounted in the ventilation outlet duct to
provide a flow of air through the enclosure. The system is designed to give a negative pressure
within the acoustic enclosure.
Positive Pressure Ventilation Fan(s) (if applicable)
Motor driven fan(s) (XM59 and if applicable XM37) are mounted in the ventilation inlet duct to
provide a flow of air through the enclosure. The system is designed to give a positive pressure
within the acoustic enclosure.
Instrumentation
Filter Differential Pressure Monitoring (if applicable)
The ventilation intake filter pressure drop is monitored by a differential pressure transmitter
(PDT27) which provides warning signals to the unit control panel.
Enclosure Differential Pressure Monitoring
The enclosure pressure is monitored by a differential pressure transmitter (PDT138) which
provides shutdown signals to the unit control panel.
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Combustion Air System
Air Inlet Filter - Marine Type (if applicable)
The combustion air intake filter (XF34) is of the high velocity, high efficiency multi-stage type
consisting of five stages.
The first stage of the filter consists of a weather hood and bird screen.
The second stage consists of a spin tube module and extractor assembly. The spin tube module
consists of a bank of spin tubes mounted in a frame. Air entering the inlet tube strikes a fixed
spinner that imparts a whirl effect, which develops a high radial velocity to the air stream. The
inertial action forces heavy contaminants in the airflow to the periphery of the tube, separating
them from the airflow. Purified air exits through a central discharge tube whilst contaminants are
carried by the secondary discharge stream into a bleed duct system. The bleed duct system
comprises a small transition section that leads to a short case axial flow fan. The fan pulls the
contaminant-laden air through the bleed duct to the outside of the filtration system.
The main filter section is a high efficiency bag type filter with an optional pre–filter bag fitted
directly in front of the main filter bags to prolong their life by removing heavy contamination.
The final stage consists of a vane separator for the inertial interception and removal of bulk
water caused by high humidity, rainfall or sea spray.
The filter housing is provided with a side or front access door for servicing of filter elements and
gas detectors (when fitted).
Where anti-icing is required a heat exchanger is mounted onto the front of the filter and provided
with hot exhaust gases ducted from the exhaust system.
For further information, refer to the Maintenance Manual.
Air Intake Filter - Pulse Type (if applicable)
The combustion air intake filter (XF34) is of the high efficiency, single stage, pulse clean type.
The filter comprises of a matrix of cylindrical filter elements, which are cleaned by means of a
reversed pulse of compressed air.
Pulsing occurs automatically when a preset pressure differential is reached; it can also be
initiated manually or via a timer to over-ride the differential pressure control signal. An additional
timer is included to over-ride the control system to inhibit the pulse at preset times e.g. late at
night.
Compressed air headers and blow tubes deliver a solenoid valve (SOL361) controlled pulse of air
that clears dust cake and any ice build up from the outside surface of the elements.
A pulse clean scavenge fan XM19 is fitted to assist removal of debris from the filter (if applicable
to this application).
For further information, refer to the vendor documentation in Volume V – Vendor Information
Manual.
Air Intake Silencer
A silencer is provided to reduce noise emissions from the turbine intake.
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Acoustic Lagging
To meet site noise emission requirements, the intake system may be acoustically lagged up to
and including the air intake silencer. As a minimum, the lagging will have sufficient physical
properties to meet the package noise level requirements.
Instrumentation
The air intake filter pressure drop is monitored by a differential pressure transmitter (PDT1)
which gives warning and shutdown signals to the unit control panel.
Exhaust System
Exhaust Silencer
An exhaust silencer reduces noise emissions from the turbine exhaust.
Acoustic and Thermal Lagging
To meet site requirements, the exhaust system may be acoustically and thermally lagged
downstream of the acoustic enclosure, up to the silencer or waste heat recovery unit (where
applicable) excluding flexible joints. As a minimum, the lagging is sufficient to ensure the outer
surface of the cladding is restricted to 55ºC for metallic cladding or 65ºC for non-metallic
cladding. This will ensure:
•
Heat is kept within the duct for overall system efficiency.
•
Acoustic attenuation.
•
Protection of personnel.
Instrumentation
A pressure differential transmitter (PDT133) situated in the exhaust duct provides indication of
exhaust gas backpressure (if applicable).
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Fire & Gas Protection System
The turbine acoustic enclosure is provided with a fire and gas monitoring system and a fire
extinguishant system to protect the installation should a gas leak or fire be detected. A
schematic diagram of the Fire System is located this Manual Volume.
General Description
The system comprises gas detectors, infrared flame detectors and heat detectors mounted in the
turbine enclosure. Fire extinguishant cylinders are mounted external to the enclosure with an
associated release mechanism, which delivers the extinguishant through pipework to nozzles
located inside the enclosure. The system is automatically controlled by the fire and gas
monitoring module located within the unit control panel. A manual extinguishant release button,
on the turbine extinguishant release control panel located on the unit control panel, enables
manual operation of the system. Audible and visual alarm units are fitted to the turbine
enclosure roof.
Ventilation dampers, which are situated in the enclosure ventilation inlet and outlet ducts, are
used to prevent the loss of extinguishant to atmosphere if a fire occurs.
System Control and Operation
A twin shot system provides initial and reserve extinguishant charges. If a fire is detected either
via the heat detector(s) or via infrared flame detectors then the turbine, all AC power supplies
and fuel is shut down and isolated. After a short time delay, the initial charge of extinguishant is
released and the DC motor driven emergency lubricating oil pump automatically starts.
If the extinguishant release is not detected by the in-line pressure switch, the reserve shot will be
released. After a successful release is detected, then any further automatic releases are inhibited
for 20 minutes. The emergency lubricating oil pump will continue to run.
Note: If a fire is considered to be due to a lubricating oil leak and being
potentially fed by the emergency lubricating oil pump, then it is the
responsibility of the operator to decide whether to switch off the pump or allow it
to continue running.
The CO2 extinguisher cylinders must be isolated from the engine package during maintenance. A
signal from the isolation valve inhibits a gas turbine start attempt when the valve is in the
isolated position.
System Components
Heat Detectors
Heat detectors (TD2A (TD2B, TD13, TD21 - optional)) are mounted in the turbine enclosure. If a
heat detector detects a fire, a fire shutdown will immediately be initiated, and the fire
extinguishant released after a predetermined time delay.
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Infra Red (IR) Flame Detectors
IR flame detectors (YD5, YD7, and YD8) are provided, suitably located to detect a fire at any
location within the enclosure.
If a detector detects a fire, a turbine shutdown will be initiated and the initial fire extinguishant
charge will be released.
Fault conditions in the infrared detection system are monitored. If a fault is detected in a
detector, a fault warning will be annunciated; if the fault is not rectified within 15 minutes the
turbine will be shutdown (not a fire shutdown).
Gas Detectors
Enclosure ventilation outlet
Two gas detectors (GD1, GD2) are provided, suitably located to detect gas exiting the enclosure
vent outlet.
The detection of gas by any single gas detector in an area will provide fault and low/high alarm
level signals. Operation of the low-level alarm will give an audible warning. Operation of the highlevel alarm will initiate a turbine shutdown, but keep the turbine enclosure ventilation fan(s)
running.
Enclosure ventilation inlet (if applicable)
Two gas detectors (GD3, GD4) are provided, suitably located to detect gas entering the enclosure
vent inlet.
The detection of gas by any single gas detector will provide fault and low/high alarm level
signals. Operation of the low-level alarm will give an audible warning. Operation of the high-level
alarm will initiate a turbine and turbine enclosure ventilation fan shutdown.
Combustion air inlet (if applicable)
Two gas detectors (GD6, GD11) are provided, suitably located to detect gas entering the
combustion air inlet.
The detection of gas by any single gas detector will provide fault and low/high alarm level
signals. Operation of the low-level alarm will give an audible warning. Operation of the high-level
alarm will initiate a turbine shutdown, but keep the turbine enclosure ventilation fan(s) running.
General
If gas is detected at ‘warning’ level then a warning will be annunciated followed 15 minutes later
by a turbine shutdown.
Prior to engine start, if gas is detected at the warning level, purging of the enclosure will take
place and a subsequent recheck. If gas continues to be present at the warning level the start
attempt will be aborted after 15 minutes. If gas is detected at the ‘shutdown’ level, purging of
the enclosure will take place, followed by a subsequent recheck. If gas continues to be present at
the ‘shutdown’ level, a start will not be permitted and should not be attempted.
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Ventilation Dampers
Dampers (YV1 and YV2), located in the enclosure vent inlet and outlet respectively, are
automatically opened during turbine operation by instrument air pressure. When the turbine is
shutdown, the controlling solenoids (SOL162 and SOL161) are de-energized and the dampers will
close under spring pressure. In the event of a fire, the dampers will therefore be closed to retain
the fire extinguishant.
Extinguishant Bottles
Four fire extinguishant bottles, two initial (XX16 and XX17) and two reserve (XX19 and XX20),
are positioned on a skid outside the turbine acoustic enclosure with connecting pipework to
nozzles within the enclosure. The bottles are suspended from automatic bottle weighing devices,
if either of the initial or reserve bottles indicates low contents a warning is annunciated on the
turbine control module. If BOTH sets of bottles indicate low contents then a warning will be
annunciated followed 15 minutes later by a turbine shutdown.
The fire extinguishant is released by either a signal from the turbine control module or by manual
actuation from the breakglass units located on corners of the turbine enclosure package
(optional) and one located on the turbine control module. The bottles give the capacity for an
initial automatic or manual release of extinguishant followed by the option of another automatic
or manual reserve release. Both sets of bottles may be manually fired by operating the manual
lever actuator located on top of the bottles.
A valve is provided adjacent to the extinguishant bottle skid for manual isolation. The valve is
fitted with limit switches to indicate when the valve is fully open or closed. When the valve is
closed the enclosure vent system trip is inhibited.
An integral safety feature of the extinguishant bottle skid is the provision of five bursting discs to
safeguard against system overpressure. The discs are positioned on the ‘initial’ first bottle (PSE4),
‘initial’ second bottle (PSE5), ‘reserve’ first bottle (PSE6), ‘reserve’ second bottle (PSE7) and
upstream of the manual shut off valve (PSE3).
Instrumentation
Pressure Monitoring
Pressure monitoring is provided as follows:
Fire Extinguishant Bottles
Pressure switches (PS8 and PS73) provide the unit control panel with a C02 Gas Gone warning for
both Initial and Reserve cylinders respectively.
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Position Monitoring
Valve position monitoring is provided as follows:
Ventilation Dampers
Position switches (ZS16 and ZS17) monitor the enclosure ventilation dampers to ensure they are
in the Open position. Position switches (ZS76 and ZS99) indicate when the enclosure ventilation
dampers are in the Closed position.
Isolation Valve
Position switches (ZS384 and ZS235) monitor the C02 Isolation valve in the Open and Closed
positions respectively.
Fire Extinguishant Bottles
Position Switches (ZS749 and ZS748) monitor the ’Initial’ C02 second bottle and first bottle low
contents respectively.
Position Switches (ZS751 and ZS750) monitor the ’Reserve’ C02 second bottle and first bottle low
contents respectively.
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Gearbox and Generator
Gearbox
The main gearbox located between the gas turbine and the generator provides speed reduction
of the turbine output shaft to that suitable for operation of the generator.
The gear unit is a single reduction parallel shaft speed reducer with vertical offset. Lubrication of
the gear units and bearings is provided by the gas turbine lubricating oil system. The gear unit is
foot mounted on to the underbase.
Gearcase-mounted accelerometers provide indication of excess vibration.
The information contained within this section provides an overview of a typical gearbox and
associated equipment. For specific manufacturer information, refer to the Driven Unit Manual.
Generator
The generator is of salient-pole construction with brushless excitation, and a permanent magnet
generator (PMG) for automatic voltage regulator (AVR) power supply. The design incorporates
accessibility to facilitate commissioning, operation, inspection and maintenance.
All the component items of the generator are fixed to the base frame, which is the main
structural member. It carries the end brackets and bearings, the stator corepack and the cooler,
which is mounted on top. The exciter and PMG stators are fixed to a bracket mounted on the end
bracket at the non-drive end (NDE). Terminals are mounted off the frame, either all on one side
or lines one side and neutrals on the other, as required.
The information contained within this section provides an overview of a typical generator and
associated equipment. For specific manufacturer information, refer to the Driven Unit Manual.
Cooling System
A fan, mounted on the generator rotor shaft, provides circulation of cooling air to the electrical
windings of the rotor and stator. This circulating cooling air inside the machine is sealed in and is
cooled by passing it through an air cooled heat exchanger mounted on the top of the generator.
The air flow to the heat exchanger is induced by fans mounted in the air inlet.
A pressure differential switch monitors air flow to the heat exchanger.
The temperature of cooling air to the generator windings is monitored by resistance temperature
detectors.
Generator Bearing Lubrication
The generator bearings are supplied with lubricating oil from the turbine lubricating oil system.
One resistance temperature detector is fitted to each bearing housing. This monitors bearing
temperature and provides warning and turbine shutdown functions if the temperature levels
reach predetermined levels.
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Vibration Monitoring
The generator is monitored for vibration by accelerometers located at the drive end and nondrive end bearings. The accelerometers provide warning and turbine shutdown functions if
vibration levels reach predetermined levels.
Generator Winding Temperature Monitoring
Resistance Temperature Detectors (RTD's) are fitted on the stator windings to monitor
temperature and to provide warning and turbine shutdown functions if the temperature levels
reach predetermined levels.
Anti-condensation Heating
Anti-condensation heaters are located to protect the generator windings and generator exciter.
Electrical Operation
The AC generator converts mechanical energy into electrical energy by electro-magnetic
induction. To produce a voltage, there must be a relative motion between the armature windings
of the stator and the field windings of the rotor. The motion is produced by the action of the gas
turbine engine turning the rotor via the gearbox.
An automatic voltage regulator (AVR) provides and controls the DC power for the excitation of
the generator.
A power factor/VAr control circuit enables the generator to operate at constant power factor or
constant VAr’s when in parallel with other generators or with the public supply.
The overcurrent limit circuit protects the AVR and generator excitation system against overloads
by limiting the maximum excitation output from the AVR.
An excitation fault detector is used to detect the malfunction of a generator caused by faulty
excitation.
Generator Control System
The generator control system protects and monitors the operation of the generator.
General Description
As required, the generator control system consists of various metering, indication, control,
protection, and synchronizing devices and instrumentation as well as the panel switches that
enable generator functions.
Operation
Control of the generator is achieved through a generator control panel (GCP). Links exist
between the GCP and the turbine control system to enable emergency stop, raise, and lower
command signals.
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Control Panels and Electrical Equipment Cabinets
Introduction
This section describes details of the control panels and electrical equipment associated with the
turbine package.
Unit Control System
The unit control system provides control signals and monitoring for all the turbine systems and
associated instrumentation to allow safe starting, normal running and shutdown of the gas
turbine.
The system, which is microprocessor-based, provides control and monitoring which includes:
•
Turbine sequencing and protection,
•
Fault monitoring,
•
Annunciation,
•
Gas turbine speed control and temperature monitoring,
•
Back up protection for safety related functions,
•
Driven unit monitoring,
•
Fire and gas monitoring.
Figure 1-1 Unit Control Panel (UCP) (onskid)
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Figure 1-2 Operator Panel
General Description
The on-package control system comprises a main controls housing mounted on the outside of the
turbine enclosure together with networked I/O nodes mounted inside the turbine package
distributed around the engine. A driven unit node is located on the driven unit end of the
package. Some modules are mounted off the package, such as the motor control center (MCC)
and battery system. The main operator interface is a remote desktop personal computer (PC) or
a touchscreen display mounted on a free standing controls cubicle.
Human / Machine Interface (HMI)
The human / machine interface is provided for unit operation, control data and status
information. The displays are selected by using a mouse to make selections via a menu system.
The Human / Machine Interface (HMI) includes on screen data trending facilities. Screens display
the information in various formats, including pictorial and tabular, and can incorporate live data
and animation. All text on the HMI is in the native language.
A typical selection of main menu functions available on the display is listed below:
1.
Unit Operation – This is the main page from which control of turbine and driven
unit can be performed. The mimic also shows summary data for the unit.
2.
Auxiliaries – This shows turbine auxiliaries such as the seal air system and drains
tank.
3.
Core Instruments – Shows bearing temperature and vibration data.
4.
Core Temperature – The temperature of the turbine core as measured by a
thermocouple ring is shown here.
5.
Fire and Gas – Summary of data from the fire and gas systems.
6.
Fuel – An overview of the fuel system is shown on this mimic. Where multiple fuels
are available to the turbine, the individual systems are also selectable.
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Turbine Package Operators Manual
Chapter 1
Turbine Package System Overview
7.
Gas Path – The temperature and pressure of air flowing through the turbine is
displayed on this mimic.
8.
Turbine Governor – This shows the state of the turbine fuel governor and allows
selection of all governing modes.
9.
Lubrication Oil –Shows the lubrication oil system for the turbine and driven unit,
indicating which oil pumps are running and giving oil pressure and temperature.
10.
Turbine Log – This page shows key data for the turbine which can be interpreted
by experienced personnel.
11.
Ventilation – Includes the enclosure ventilation fans, flow detection and related
items such as inlet filters and enclosure dampers.
12.
Driven Unit – A group of mimics provide access to driven unit control and
monitoring.
Generator Monitoring & Control
The control system provides a mixture of digital and analogue I/O for the generator sequencing /
monitoring and alarm protection. The exact configuration is dependent on the generator
instrumentation and electrical interface, but would typically include:
•
Monitoring of the Shutdown Sequencing and Protection relays,
•
Generator Control Panel Speed Control and synchronizing unit interface,
•
Instrument Fault Monitoring,
•
Message Annunciation,
•
Generator Winding and Bearing Temperature Monitoring and Protection,
•
Generator Cooling Control and Monitoring,
•
Vibration Monitoring of the generator non-driven and drive end seismic probes.
Generator Control Panel (GCP)
Normal control of the generator is achieved from the HMI via a generator control panel (GCP).
Links exist between the GCP and the turbine control system to enable emergency stop and
raise/lower command signals.
The generator control panel also protects and monitors the operation of the generator.
Description
The GCP consists of a cubicle housing various metering, indication, control, protection, and
synchronizing devices and instrumentation as well as the panel switches which enable the
generator functions.
Access into the cubicle can be gained through a front mounted door. Opening the door will
activate a light within the cubicle.
For more specific details of the GCP refer to the ACTEMIUM literature contained in the Vendor
Information Manual.
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Chapter 1
Turbine Package System Overview
Batteries & Battery Charging System
The DC supply is provided by 24 volt batteries and a battery charger. The supply is directed
through a DC distribution plate to the package systems.
The battery system is designed to have the capacity to run the DC motor driven emergency
lubricating oil pump for three hours in the case of a mains failure.
Battery Charger & System Controller
The battery charger is housed in a freestanding steel enclosure, which also contains the
batteries, DC-DC converters, and a system controller. The system controller allows the user to
configure, monitor and control the entire DC power system from a touch screen display. In
addition to local indicators and alarms, the system controller also has Ethernet communication
capabilities.
24 Volt Batteries
24 volt NiCad battery, plastic cased, consisting of 20 cells having a nominal capacity of 550Ah.
The cells are designed for optimal operating in an ambient of 25ºC.
The cells are mounted on a battery rack.
24 Volt DC Battery Charger
The 24 volt battery charger is housed in a freestanding steel cubicle.
The equipment comprises a 24V 3k1W Rectifier module, a CXCR Controller, 24V battery and
associated protective devices. The rectifier will support any standby load and recharge the
associated battery.
Local indicators and alarms provide indication of voltage/current, charge/charge failure, and
mains supply.
Contacts are also included to provide remote indication of mains and charger failure.
For more specific details of the Batteries and Battery Charger refer to the Alpha-Argus literature
contained in the Vendor Information Manual.
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