Erawan ECP Compressor Control Upgrade O&M Training - Full Version

7/7/2015Erawan ECP Compressor ControlUpgrade - O&M TrainingSession# 1: 08-09 July 2015 (Settapat, SKL)Session# 2: 29-30 July 2015 (Settapat, SKL)© 2013 ChevronErawan ECP Compressor Control Upgrade 08:00-08:30O&M Training 08:30-12:00 13:00-14:30Day : 1 14:30-17:00 1 Introduction and objective 2 Fundamental Knowledge - Turbine Package Operation 08:00-09:30 3 Fundamental Knowledge - Compressor 09:30-10:30 4 Compressor Package Unit Overview 10:30-12:00Day : 2 4 Compressor Package Unit Overview (Continue) 13:00-14:00 5 HMI Screen and Function 14:00-16:00 Starting Sequence  Wet Seal System, Enclosure Vent Fan 6  Yard Valve Sequence  Lube Oil Check  Fuel Gas Valve Check 7 Stop Sequence 8 Anti-Surge Control, Process Control and Load Sharing System Morning Break : 10:00-10:15 Lunch : 12:00-13:00 Afternoon Break : 14:45-15:00© 2013 Chevron 2 1

7/7/2015 Erawan ECP Compressor Control System Upgrade – Mechanical© 2013 Chevron 3 ERCP Control Upgrade O&M Training: Gas Turbine Engine Fundamental Comparison of working cycles for turbojet engine and 4-stoke piston engine.© 2013 Chevron 4 2

7/7/2015 ERCP Control Upgrade O&M Training: 5 Gas Turbine Engine Fundamental Gas Turbine Engine • This air is first drawn into the engine where it is compressed, mixed with fuel and ignited. • The resulting hot gas expands at high velocity through a series of airfoil-shaped blades transferring energy created from combustion to turn an output shaft. • The residual thermal energy in the hot exhaust gas can be harnessed for a variety of industrial processes.© 2013 ChevronERCP Control Upgrade O&M Training:Gas Turbine Engine Fundamental© 2013 Chevron 6 3

7/7/2015ERCP Control Upgrade O&M Training:Gas Turbine Engine Fundamental_ Terminology• T1, Air temp before enter Air • Air Compressor, Turbine Compressorcompressor • GP Turbine, Turbine• PCD,CDP,P2 • Power Turbine• T5,EGT,ECT (T4) • Air Inlet duct• T7, Power turbine exhaust temp • Exhaust Duct• Trit, TET, TIT, T3 • Air filter• NGP, GG speed,N1 & N2 • Light off & Flame out• NPT, N3 • Single shaft & Multiple shaft• VIGV, IGV • Single spool& Double spool & triple• Bleed Valve spool• Q = Energy or Heat© 2013 ChevronERCP Control Upgrade O&M Training:Gas Turbine Engine Fundamental© 2013 Chevron 4

7/7/2015ERCP Control Upgrade O&M Training:Gas Turbine Engine Fundamental_Diffuser & Nozzle Divergent>> Convergent>> 9© 2013 Chevron ERCP Control Upgrade O&M Training: Gas Turbine Engine Fundamental© 2013 Chevron 5

7/7/2015ERCP Control Upgrade O&M Training:Gas Turbine Engine Fundamental_T-s DiagramTRIT Limit GP Turbine (= Work input) Work 5 input Useful Work, UW© 2013 ChevronERCP Control Upgrade O&M Training:Centaur Gas Turbine Familiarization© 2013 Chevron 6

7/7/2015ERCP Control Upgrade O&M Training:Centaur Gas Turbine Familiarization© 2013 Chevron ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization© 2013 Chevron 7

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationCentaur50 Engine cut-awayand Breakdown detail© 2013 Chevron 15 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization© 2013 Chevron 16 8

7/7/2015ERCP Control Upgrade O&M Training:Centaur Gas Turbine Familiarization© 2013 Chevron 17PACKAGE MAIN ASSEMBLIESAIR FILTER EXHAUST GAS IN GAS OUT HOOD FANS VENT VENT IN OUT GAS PATH PLENUM GAS GENERATOR POWER TURBINE ENCLOSURE SYSTEMS GAS COMPRESSOR BASE FRAME© 2013 Chevron 18 DRIVER UNIT 9

7/7/2015ERCP Control Upgrade O&M Training:Centaur Gas Turbine Familiarization© 2013 Chevron 19 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Major components of Gas Turbine ● Axial Compressor ● Combustor ● Injector ● Gas Generator Turbine ● Power Turbine© 2013 Chevron 20 10

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationAir Inlet and Axial Compressor Section© 2013 Chevron 21 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Axial CompressorRotating Part Stator part© 2013 Chevron 22 11

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationAxial Compressor Rotating Part Stator part© 2013 Chevron 23 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationAxial Compressor© 2013 Chevron 24 12

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationAxial, Centrifugal and Recip Type of Compressor  Application of radial, Axial and Recip Performance characteristics of different types of compressors.© 2013 Chevron 25 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationAxial Compressor Wash Characteristic© 2013 Chevron 26 13

7/7/2015 ERCP Control Upgrade O&M Training: 27 Centaur Gas Turbine Familiarization Axial Flow Compressor Degradation Over time, a number of factors can cause both recoverable and non recoverable engine performance degradation. Non recoverable degradation results from physical wear and damage to engine internal components, and can only be recovered with major in-shop inspection and repair maintenance.© 2013 Chevron ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationGas Combustor© 2013 Chevron 28 14

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationGas Combustor© 2013 Chevron 29 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Gas Combustor© 2013 Chevron 30 15

ERCP Control Upgrade O&M Training: 7/7/2015 Centaur Gas Turbine Familiarization 31 Annular Type Combustor • Advantages • “Clean” aerodynamic design, and hence low pressure loss. Compressor and turbine ducting is simple and lightweight • Minimum overall length, weight, and diameter • Problem of “light round” avoid • Disadvantages: • Difficult to develop, necessitates full engine air flow. • Poses formidable mechanical problems, due mainly to high bucking load on outer flame tube wall. • Poor matching of fuel spray with secondary air jets. This is because it is only possible for these air jets to penetrate in two directions, i.e. radically inwards and radially outwards. • More difficult to obtain stable uniform outlet temperature profile than for a tubular chamber.© 2013 Chevron ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Annular Type Combustor© 2013 Chevron 32 16

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationAnnular Type Combustor© 2013 Chevron 33ERCP Control Upgrade O&M Training: 34Centaur Gas Turbine Familiarization 17Fuel Ring and Fuel InjectorThe gas fuel injector is part of a gas fuel Fuel Ringmanifold assembly and its manifold-to-injector tube assemblies. Twenty-one fuel Fuelinjectors are installed on the gas fuel Injectormanifold assembly. The fuel manifoldassembly, bolted to the combustor housingby mounting brackets, incorporates an inletfuel boss and twenty-one outlet bosses forconnection of the manifold-to-injector tubeassemblies. The manifold-to-injector tubeassemblies feed gas from the manifold tothe injector bosses on the combustorhousing, and to the gas fuel injectors. Airswirlers aid in mixing gas with compressordelivery air.© 2013 Chevron

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationFuel Injector© 2013 Chevron 35 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Torch Ignitor© 2013 Chevron 36 18

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationFirst Stage Nozzle© 2013 Chevron 37 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Hot Gas Turbine© 2013 Chevron 38 19

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationHot Gas Turbine© 2013 Chevron 39 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Turbine Wheel© 2013 Chevron 40 20

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationTurbine Blade© 2013 Chevron 41 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Air Cooling System© 2013 Chevron 42 21

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationTurbine Blade Cooling System© 2013 Chevron 43 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Turbine Blade Cooling System© 2013 Chevron 44 22

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationAir Sealing System© 2013 Chevron 45 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Lube oil System© 2013 Chevron 46 23

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationPackage Control System© 2013 Chevron 47 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Basic Control SystemConcept© 2013 Chevron 48 24

7/7/2015 ERCP Control Upgrade O&M Training: Centaur Gas Turbine FamiliarizationPackage Control System Architecture© 2013 Chevron 49 ERCP Control Upgrade O&M Training: Centaur Gas Turbine Familiarization Fire and Gas System© 2013 Chevron 50 25

7/7/2015Erawan ECP Compressor ControlSystem Upgrade – Control System© 2013 Chevron 51 Compressor Fundamental 52 Requirement for Gas Compression 26 Gas compression is required when it is necessary to flow gas from a lower pressure to a higher pressure system. Booster compressors are also used on long pipelines, to restore pressure drop lost to friction. The design of a long pipeline requires trade-off studies between the size and distance, and requirement for booster compressors.© 2013 Chevron

7/7/2015Compressor FundamentalCompressor TypesThere are various types of compressors. However, the compressors can becategorised by their principles into two groups – > Positive Displacement • - Reciprocating • - Rotary – > Centrifugal© 2013 Chevron 53 Compressor Fundamental Compressor Types© 2013 Chevron 54 27

7/7/2015Compressor FundamentalCompressor TypesPositive DisplacementReciprocating Compressor – Positive displacement machine in which the compressing and displacing element is a piston moving linearly within a cylinderRotary Compressor – Positive displacement machine in which compression and displacement of gas is accomplished by the positive action of rotating elementCentrifugalCentrifugal Compressor – Rotary continuous flow machine when the rotating impellers impart a velocity head to the fluid which is converted to pressure head by the diffuser© 2013 Chevron 55Compressor FundamentalCentrifugal Compressor© 2013 Chevron 56 28

7/7/2015 Compressor Fundamental 57 Centrifugal Compressor Centrifugal compressors are kinetic machines. The centrifugal compressors use a series of rotating impellers to impart velocity head to the gas. This is then converted to pressure head as the gas is slowed in the compressor case. Centrifugal compressors have low vibration and high ratios of horsepower per unit of space and weight, which makes them very popular for offshore application. However centrifugal machines have low efficiency, specially at low throughput rates (< 200 acfm). They require more horsepower to compress the same flow rate than reciprocating compressors. Centrifugal compressors are generally driven by either electric motor, steam or gas turbine, or turbo expander© 2013 ChevronCompressor FundamentalCentrifugal Compressor© 2013 Chevron Conversion of velocity energy to pressure – - Velocity energy (acceleration) is added to the gas by the rapidly rotating impeller – - Part of this energy, results in a static pressure rise of the gas in the impeller – - After leaving the impeller, the gas enters a diffuser, which is a stationary component, where its slows down resulting in an additional pressure increase – - After leaving the diffuser, the gas either exits the compressor case after single stage compression or enters the eye of the impeller for multi-stage compression. 58 29

7/7/2015Compressor FundamentalCentrifugal Compressor Type Horizontal split casing – Split along the rotor assembly – Top and bottom halves are bolted and doweled together – Advantage: Ability to inspect, clean and replace the compressor internals by simply lifting off the top half of the case. – Disadvantage: Possible leaks between the stage. – Inability to handle high pressures due to sealing limitations at the split.© 2013 Chevron 59Compressor FundamentalCentrifugal Compressor Type Vertically split casing – Rotor assembly and diaphragms are housed in a enclosed cylinder – Inner barrel portion of a vertically split casing can only be removed from an end – Advantage: high pressure capability due to the one piece construction and conventional, proven flange type seals at each end. – Disadvantage: Internals must be removed for inspection and cleaning – Sufficient space must be allowed for removing the rotor assembly.© 2013 Chevron 60 30

7/7/2015Compressor FundamentalCentrifugal Compressor: Performance Maps Centrifugal compressor performance is usually expressed in terms of a group of curves that graphically display the range of – - Flows – - Efficiencies – - Heads – - Speeds© 2013 Chevron 61Compressor FundamentalCentrifugal Compressor: Performance Maps Head vs. Capacity. – Isentropic head and flow are the coordinates and are plotted for lines of constant • - Speed • - Isentropic efficiency (%) • - Surge limit line  Line to the right of the surge limit line is referred to as the surge control line • - If any two values of a compressor’s operating point are know, the other two values can be determined from the map© 2013 Chevron 62 31

7/7/2015Compressor FundamentalCentrifugal Compressor: FlowInlet, or actual flow • Amount of volume throughput per unit of time at the inlet to the compressor • Normally expressed in actual cubic feet per minute (ACFM) • Useful means of specifying compressor throughput provided that the inlet pressure and temperatures of the gas are specified. • The capacity of a compressor is sensitive only inlet actual flow (ACFM) • Actual volume flow is a function of mass flow and the specific volume of the gas at suction conditions© 2013 Chevron Where: ACFM = Actual ft3/min Qg = Gas flow rate, MMSCFD 63 Compressor Fundamental 64 Centrifugal Compressor: Surge 32StallFlow through the impeller and diffuserDuring normal flow conditions a uniform film(boundary layer) of gas is formed on both sides ofthe impeller vane passageWhen the boundary layer is continuous, the entirediameter of the impeller is effectively used forproducing headAs the flow is reduced or pressure ratio across theimpeller increases, this boundary layer breaks down(Stalls) at the impeller tip causing recirculationRecirculation reduces the impeller surface areaused to accelerate the gas and the energy of thegas cannot overcome the pressure in the diffuserThis resulting back-flow occurs until diffuserpressure is equalised with the gas leaving theimpeller.The boundary layer then reforms, and the pressurebuilds until it is again too high causing the boundarylayer to breakdownThe rapid breakdown and subsequent reforming ofthe boundary layer characterises violent surge© 2013 Chevron

7/7/2015Compressor FundamentalCentrifugal Compressor: Surge© 2013 Chevron Surge – Operating point at which unstable operation occurs – Low-flow limit of a compressor at a particular operating speed – To the left of the surge limit point, a compressor’s head making capability decreases as flow decrease – Every compressor has an operating point of minimum flow and corresponding maximum head, and, if exceeded, will no longer perform in a stable manner – The limits are exceeded when the back pressure on the system cannot be overcome by the head produced 65Compressor FundamentalCentrifugal Compressor: Surge– Back-and forth flow motion (surging) occurs inside the compressor which can be very damaging to the rotating components– During the flow reversals of surge, loud clattering noises will be heard from the compressor– If allowed to continue operating, the compressor will sustain severe internal damage© 2013 Chevron 66 33

7/7/2015Compressor FundamentalCentrifugal Compressor: Surge Control© 2013 Chevron  A compressor can be brought out of a surge condition by reducing the head and/or increasing flow  Also, depending on the existing speed and the slope of the surge line, increasing the compressor speed may bring it out of surge.  Primary means of avoiding surge is increasing flow through the compressor  The easiest and most common way to do this is to open a by-pass or recycle valve which allows discharge gas to be recirculated to the suction  A surge control system [composed of various components which send and receive signals from flow and pressure measuring devices] operates this valve by sensing that the compressor is nearing to operating in surge 67 Compressor Fundamental 68 Centrifugal Compressor: Surge Control 34Recycle valve– At constant speed the head-capacity relationship will vary in accordance with the performance curve. For all compressor speeds: • - As flow rate to the compressor decreases the compressor approaches the surge point • - As discharge pressure increases compressor flow rate will decrease and the surge point is approached • - As suction pressure decreases, and discharge pressure remains constant, the compressor head must increase, approaching the surge point in the process © 2013 Chevron

7/7/2015Compressor FundamentalCentrifugal Compressor: Stone wallPoint at which a compressor is operating at maximum flow and minimum headwhen this point is reached for a given gas– - Impellers are physically unable to handle the gas– - Flow through the compressor can not be increased without further internal modifications– - Point is also known as chocked-flow, since it is a point at which the highest stable flow occurs– Stone wall will cause • > A noticeable drop in pressure • > Increase in vibration due to turbulent flow within the compressor • > Increased vibration could damage the compressor • > Operation in this region causes excessive use of horse power, occasionally to the point of overload© 2013 Chevron 69Compressor FundamentalCompressor Operating Range • Surge control line • Minimum governing speed curve • Maximum continuous speed (MCOS) Curve • Stonewall • High Discharge Pressure of the compressor • Maximum Horse Power Limitation Curve© 2013 Chevron 70 35

7/7/2015Erawan Phase ISeal oil system improvement© 2013 Chevron Why Wet Seal?  Sealing process gas from compressor barrel to atmosphere  Carbon seal has theoretically unlimited service life© 2013 Chevron 36

7/7/2015How does wet seal work?© 2013 Chevron Key components of old wet seal system  Main seal oil pump driven by Engine via Accessory Gear Box (AGB)  Auxiliary seal oil pump driven by starting gas via pneumatic motor  Pressure relief devices  Seal oil dP transmitter  Seal oil regulator  Seal oil bypass flow regulator  Seal oil rundown tank  2 x carbon seal inside bearing housing  Seal oil trap© 2013 Chevron 37

7/7/2015 Why upgrade existing seal oil system?  SASBU experienced fire case at Solar compressor package running on wet seal system. During black out event, there was no starting gas supplied to auxiliary pump so no sealing oil provided. Accidentally, Blow down valve stuck closed and Suction/discharge SDV stuck open. As a result pressure traps inside compressor barrel and lack of sealing oil. Without sealing oil, Gas entrains to lube oil tank causing high LEL in lube oil tank. Then, explosion occurred causing fire inside package.  To mitigate risk of high LEL in lube oil tank during blackout event, backup seal oil system has been introduced.© 2013 Chevron Key components of upgraded wet seal system  Main seal oil pump driven by Engine via Accessory Gear Box (AGB)  Auxiliary seal oil pump driven by starting gas via pneumatic motor  Backup seal oil pump driven by starting gas or compressor casing gas via pneumatic motor  2 x carbon seal inside bearing housing  Pressure relief devices  Seal oil dP transmitter  Seal oil regulator  Seal oil bypass flow regulator  Seal oil rundown tank  Seal oil trap  Emergency circuit module© 2013 Chevron 38

7/7/2015Wet seal system schematic© 2013 ChevronSimple loop diagram of Seal oil pumps Compressor CasingMain AGB Centaur 40Pump engineAux Pneumatic Starting GasPump (Motive Force) motor BU Pneumatic Pump motor© 2013 Chevron 39

7/7/2015 Emergency Seal Oil Pump - Operating Philosophy 1. A function check of emergency seal oil pump is performed during package start, before the auxiliary pump is activated. Failure of the emergency seal oil pump check aborts the start. 2. If the emergency seal oil pump is successful, but the auxiliary pump does not start and run, the start cycle is aborted and “Aux Seal Oil Pump Failure” annunciates. 3. Periodic (daily) checks of the auxiliary and emergency seal oil pumps are performed when the unit is online. The auxiliary pump is checked at 1 PM and the emergency seal oil pump at 3 PM. A prerequisite for the check is that there must be pressure in the compressor case. A failure of the auxiliary pump check gives an alarm while the emergency seal oil pump check failure gives an alarm plus a two hour window to resolve the problem before a shutdown occurs. 4. If the auxiliary pump is required but loses motive force, the emergency seal oil pump will be activated. The package continues to run provided the emergency seal oil pump maintains seal oil dP. It will shut down immediately if seal oil dP is lost. 5. If the auxiliary pump is required and seal oil dP is lost, the emergency seal oil pump will be activated and an alarm of “Aux Seal Oil Pump Failure” annunciates. 6. Once on load, the auxiliary pump is no longer used. A loss of seal oil dP will activated the emergency seal oil pump. 7. Failure to build back seal oil dP on the emergency seal oil pump results in a package shutdown with motives gas provided through the compressor case supply 8. A total loss of primary motive gas results in a package shut down with motive gas to run the emergency seal oil pump on shut down provided through the compressor case supply© 2013 ChevronCompressor Package Unit Overview© 2013 Chevron 80 40

7/7/2015 Erawan ECP Compressor Control Upgrade – O&M Training : Scope of project In Skid : Instrument and Control Scopes  Upgrade UCP to Turbotronic™ 4 Control System : New 2 bay cabinet.  Install new NEMA 4X package skid JB  Package instrumentation upgrades (Related in skid transmitter required for TT4 control)  Replace vibration monitoring system by BN1701 series  Engine and compressor performance map display and embedded logic compressor anti-surge control© 2013 Chevron Erawan ECP Compressor Control Upgrade – O&M Training : Scope of project In Skid : Electrical Scopes  Fire & Gas detection system upgrade : EQP and Det-Tronic  24 Vdc battery/charger replacement and upgrade  Electronic Fuel Module : Gas Standard Combustion (PECC 1.5” 24 Vdc)  Electronic IGV and BV (24 Vdc system)© 2013 Chevron 41

7/7/2015 Erawan ECP Compressor Control Upgrade – O&M Training : Scope of project Electrical, Control and Instrument Scope  Install upgrade kit for anti-surge valve (Feedback Position)  Interface with SIS/FGS System  Interface with DCS System  Interface with MCC Cubicle.  Install new Junction box for Yard Valve / Anti-Surge Valve (ASV)  Connect existing Field instruments to new UCP.© 2013 Chevron Erawan ECP Compressor Control Upgrade – O&M Training : Scope of project New 2 Bay UCP New Battery 84 In Battery Room 42© 2013 Chevron

7/7/2015Erawan ECP Compressor Control Upgrade – O&MTraining : Scope of project Upgrade F&G 2N4eVwdcFuIGelV Equipments GaansdSBkVid Pneumatic BU Seal Oil Pump New Fuel NEMA 4X Gas Skid Package JB© 2013 ChevronErawan ECP Compressor Control Upgrade – O&MTraining : Scope of project SWGR Room MCC Battery Cubicle Charger End Devices End Devices End DevicesEnd Devices End Devices JB JB Existing Exp. Box For Pass through Conduit PCS FSG SIS Metal Clad Cable NEMA 4X Package JB Control Room In-Skid (S/D by Solar) Out-Skid (Pre-work by CTEP)© 2013 Chevron 43

7/7/2015Erawan ECP Compressor Control Upgrade – O&MTraining : Scope of project Fuel Gas JB Conduit Skid Metal Clad Cable In-Skid (S/D by Solar) IGV BV Out-Skid (Pre-work by JB JB CTEP) Existing Exp. Box Control Room For Pass through Battery NEMA 4X Package JB ChargerSWGR Room© 2013 ChevronErawan ECP Compressor Control Upgrade – O&MTraining : Scope of project Device Anti-Surge Valve Yard Valve FY ZS XSV PDT ZS XSV Vib. End Device JB JB Trans Rack Prox. Box JB Existing Exp. Box For Pass through Conduit NEMA 4X Package JB Metal Clad Cable In-Skid (S/D by Solar) Control Room Out-Skid (Pre-work by CTEP)© 2013 Chevron 44

7/7/2015Erawan ECP Compressor Control Upgrade – O&MTraining : Scope of project FD FD FD Existing Fire Suppression GD TD Control Room FD GD TD FD FD Existing Exp. Box For Pass throughConduit NEMA 4X Package JBMetal Clad CableIn-Skid (S/D by Solar)Out-Skid (Pre-work byCTEP)© 2013 ChevronErawan ECP Compressor Control Upgrade – O&MTraining : Scope of project DCS SIS FGSUCP UCP UCP UCP6100 6120 6140 6160 LAN-SW Hard Wire DCS Comm. CNet RG-6 ENet Cat-6 MODBUS© 2013 Chevron 45

7/7/2015Erawan ECP Compressor Control Upgrade – O&MTraining : Control System Overview TT4000 HMIDCS & MUD Turbine Control Panel Control Logic Processor IO ModuleEtherNet Termination CNet Redundance Media Termination Vibration Monitor Fire System Back Up Relay TT4000SConnection to Package and field Instruments© 2013 ChevronControl System Overview - Starting System© 2013 Chevron 92 46

7/7/2015Control System Overview - Starting System Upon completion of the pre-lube cycle and prestart requirements, the control system activates the start system. Pilot pressure opens the starter inlet pressure regulator/shutoff valve, providing pneumatic pressure to the starter motor to begin turbine rotation (breakaway). After a preset time the purge crank cycle begins. During the purge crank cycle, the engine rotates with the primary fuel valve closed and ignition deactivated, while the purge timing circuit times out. This creates airflow through the engine and exhaust system to remove combustibles. After the purge cycle is completed, the starter inlet pressure regulator/shutoff valve is opened completely to provide full cranking pressure to the starter motor. During start acceleration, the fuel system and ignition systems are activated. When the engine reaches 60 percent engine speed (Ngp), the starter shuts down, the starter clutch overruns, and the engine accelerates under its own power.© 2013 Chevron 93Control System Overview - Starting SystemConstant Speed Reference : 24% - 28% NGP- Crank Speed : 65% NGP- Drop Out SpeedRamp Rate for Each Speed : 1.5% NGP/Sec.- Ramp Rate to Crank speed : 0.2% NGP/Sec.- Ramp Rate to Starter Drop Out Speed 60% NGP : 5.0% NGP/Sec.- Ramp Rate to idle speed© 2013 Chevron 94 47

7/7/2015Control System Overview – Fuel System© 2013 Chevron 95Control System Overview – Fuel SystemFuel System works with the control system to schedule fuel flow during engineacceleration and operation under load. The control system provides over temperature andover speed topping control of the fuel system flow, and also provides automatic shutdown ifthere is a malfunction.The fuel system consists of the following interrelated systems.  Fuel Metering System  Pilot System  Compressor Air System (Pcd)Fuel Metering System - The fuel metering system consists of shutoff valves, supplymanifolds, flow control valves, and fuel injectors. The control system monitors the fuelmetering system to regulate fuel flow to change engine speed (Ngp) and temperature (T5).© 2013 Chevron 96 48

7/7/2015Control System Overview – Fuel SystemPilot System - Pilot system pressure is provided from a port on the main fuel supplymanifold or from an external compressed air source. The pilot system supplies pressure tothe pneumatically actuated fuel shutoff valves. Each pneumatically actuated shutoff valveis connected to a solenoid valve. When activated by the control system, the solenoid valveopens to allow pilot pressure to open the shutoff valve. When the solenoid valve closes,pilot pressure vents, and the shutoff valve closes. The pilot system is a fail safe fuel shutoffin the event of control system failure.Compressor Air System (Pcd) - The engine compressor air system supplies compressordischarge air (Pcd) to various systems. Tubing is connected to ports on the enginecompressor that distribute pneumatic pressure to system components. In the fuel system,Pcd is measured to determine fuel flow metering, to purge fuel lines and injectors and toclose exhaust diffuser drain valves.© 2013 Chevron 97Control System Overview – Fuel SystemValve Check Sequence Before each startup, the control system tests the integrity of the shutoff valves. To verify operation, gas fuel pressure is applied to the primary and secondary shutoff valves. The valves must hold pressure and open and close when commanded. If either shutoff valve fails, the control system annunciates a valve check failure and aborts the start cycle.© 2013 Chevron 98 49

7/7/2015Control System Overview – Fuel SystemPurge Crank Cycle After the valve check sequence is completed, the purge crank cycle is begun to remove combustibles from the engine exhaust system. To purge, the start system cranks the engine to move air through the exhaust system until the timer completes its cycle. The purge crank cycle timer is programmed according to package exhaust system volume.© 2013 Chevron 99Control System Overview – Fuel SystemIgnition Sequence After the purge crank cycle is completed, the starter continues to crank the engine. The primary and secondary shutoff valves open to supply gas fuel to the fuel control valve. The gas torch shutoff solenoid valve opens and gas fuel flows through the torch and is ignited in the presence of combustion air.© 2013 Chevron 100 50