generator and auxiliaries
DESCRIPTION
about generator & AuxiliariesTRANSCRIPT
April 26, 2023 PMI Revision 00 1
POWER PLANT OPERATION
GENERATOR & AUXILIARIES
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April 26, 2023 PMI Revision 00 2
Presentation outlineSeal Oil System line up
Hydrogen filling
Stator Water System line up
Generator Synchronization
LP heater charging
Load Raising
LP & HP heater charging
April 26, 2023 PMI Revision 00 3
SEAL OIL SYSTEM
OILCOOLER
FILTERS
DPRV
CONSTANT PRESS. REGULATORS WITH ORFICE PLATES
VACCUM PUMP
BEARGDRAINS
TG
1 2
EEBEARINGTEBEARING GAS
EXHAUST
FROM GASSYSTEM
IOT
VACUUMTANK
SOST
SOPSOP-3 DC
DPSW
TS ESFR
FLOW M. PS PG
April 26, 2023 PMI Revision 00 4
SEAL OIL SYSTEM CHARGING• Commissioning of seal oil system will be required
when the 1) generator to be filled with hydrogen or air.2) machine to be put on barring gear
• Prior to commissioning make sure that all instruments and devices are ready for operation after calibration, overhauling and trial.
April 26, 2023 PMI Revision 00 5
SEAL OIL SYSTEM CHARGING• Seal oil system has to be filled with oil• Prerequisite for oil filling
1) set all level switches2) close all stop and non-return shut off valves3) open all pressure gauge and pressure switches isolating valves4) open pressure transducer isolating valves5) open isolating valves of impulse lines of differential pressure regulator6) bearing lube oil system is in service
April 26, 2023 PMI Revision 00 6
SEAL OIL SYSTEM CHARGING• Open isolating valve of seal oil storage tank to seal
oil system. Oil will start filling the seal oil system• Open valves in oil flow path • Take coolers and filters into service• After oil is filled up into the system level will be
visible in the gauge glass of the SOT• Take governing oil system into service• Start AC seal oil pump• To clear air locking seal oil pump should be
switched on and off till its discharge pressure gauges shows a constant pressure
• Vent DPRV-A and DPRV-B
April 26, 2023 PMI Revision 00 7
SEAL OIL SYSTEM CHARGING• Vent both the coolers one by one• Vent filters• Vent pressure gauges, pressure switches and
transmitters• Set seal oil pressure by DPRV-A • Stop AC seal oil pump and set DPRV-B
(<0.3Kg/cm2 from DPRV-A) • Set thrust oil pressure (0.5 Kg/cm2 more than seal
oil pressure)• Take vacuum pump into service and adjust SOT
vacuum as recommended
April 26, 2023 PMI Revision 00 8
SEAL OIL SYSTEM CHARGING• Check all the meter readings are within limit • Check seal oil flow is as per system requirement.• Check automatic starting of stand by DC seal oil
pump by different interlocks including alarm• Check function of level switch of SOT, seal oil
storage tank and pre-chambers• After seal oil temperature reaches 300C start
cooling water flow to seal oil cooler and adjust the flow in such a way so that the seal oil temperature is maintained at 400C
April 26, 2023 PMI Revision 00 9
H2 DISTRIB
HYDROGEN
CO2VAPOURIZER
TOSEALOIL DPT
H2 DRIER
HYDROGEN COOLING SYSTEM
CO2
ANALYZER
DRAIN
AIR
FILTER
OP
DPI
April 26, 2023 PMI Revision 00 10
HYDROGEN COOLING SYSTEM• PRE CHECHS• Overhauling of gas drier has been carried and the drier is
boxed up• Check all instruments are in position after calibration• Functionally check the gas drier system• Check the availability of adequate no of CO2 filling point and
adequate no of co2 cylinders.• Check availability of adequate no of Hydrogen filling points
and cylinders.• Check whether the relief valves in the high pressure valves
are alright.• Check the generator is completely boxed up & it’s air
tightness test is successfully completed.• Check the seal oil system is in service.
April 26, 2023 PMI Revision 00 11
Purging of Air By CO2 • CO2 is admitted from CO2 manifold to generator casing at
bottom by opening the valves on cylinder and regulator.• Rate of admission is being controlled normally by regulating
the valves on the manifold. • To avoid excessive frosting, the CO2 flow rate should be
carefully regulated.• When CO2 percentage reaches 98%, the filling of CO2 can
be stopped and preparation for filling hydrogen can be made.
• After achieving 98% CO2 concentration and a pressure of 0.15 to 0.2 Kg/cm2 inside the machine, filling of hydrogen in machine can be started.
April 26, 2023 PMI Revision 00 12
H2 FILLING• Hydrogen is admitted into the generator through hydrogen
feed pipe which is connected to perforated pipe header inside the generator extending along the length of the cooling at the top.
• During process of filling with H2 the CO 2 air mixture is discharged through CO2 feed pipe from bottom.
• During H2 filling, continuously analyze the concentration of H2 in gas mixture inside the machine.
• Continue purging till hydrogen purity reaches above 98% and H2 pressure attains rated value.
• Take drier into service.• Take gas coolers into service.• Vent the coolers and establish flow.
April 26, 2023 PMI Revision 00 13
STATOR WATER SYSTEM
DIFF PRESS SWITCH
VACUUM PUMPS
POLISH UNIT
FILTERS
COOLERS
PUMPS
GAS TRAP FLOW METERS
CONDUCTIVITY
EXPANSION TANK
MAKE UP
FSIIDIFF PRESS.
MAGNET FILTER
April 26, 2023 PMI Revision 00 14
Stator Water System• For commissioning the system the system has to
be filled up first• Prerequisites for filling the cooling circuits
a. Circuit should be flushedb. Installation of pump and motors after O/Hc. Filters cleaned and boxed upd. Coolers and all other components are boxed upe. Ion exchanger is ready and is in servicef. All instruments and measuring devices are in
position after their calibration
April 26, 2023 PMI Revision 00 15
Stator Water System• System should be lined up for filling.• Complete stator water system should be filled with
DM water having required quality.• All air should be vented from the system before
starting of the pump.• Take trial of the water pumps.• Check the stand by pump for automatic starting• Adjust level regulator in the expansion tank.• Check all the instruments and meters for their
proper functioning.
April 26, 2023 PMI Revision 00 16
Stator Water System• Adjust make up water pressure around 2.0Kg/cm2
• Adjust small water flow through the gas trap• Check there is no leakage of water in the system• Take ejector into service• Take one cooler into service• Check emergency switching in circuit of the stand by water
pump• Check high and low alarm of the expansion tank• Check high conductivity alarm and tripping• Check pump discharge pr., filter diff. pr., conductivity, flow,
inlet winding pr., winding diff. pr., vacuum in expansion tank, motors current
April 26, 2023 PMI Revision 00 17
GENERATOR SYNCHRONISATION
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Check before synchronisation• CHECK all the generator Parameters are healthy• Stator cooling water flow more than 21 T/Hr.• Stator cooling water temp less than 40 oC.• Cold end hydrogen temp less than 40 oC• Seal oil pressure at turbine and 5.0 KSC• Seal oil pressure at exciter end 5.0 KSC• Seals oil D.P. between1.2 -1.5 KSC• Generator stator water specific conductivity is less than 5 m
mho/cm• Gen. hydrogen and stator water coolers are charged and
''Clarified water pressure to hydrogen & stator water coolers low'‘ alarm is not on.
April 26, 2023 PMI Revision 00 19
Check before synchronisationCHECK before closing the field breaker before synchronization• Turbine RPM is more than 2980 rpm. Generator isolators are
closed from switchyard.• Generator excitation control is on REMOTE.• Generator excitation control is on MANUAL OR AUTO.• AUTO/MANUAL excitation controllers are on HOME position.• CLOSE the generator field breaker.• Generator field breaker gets closed & Generator voltage
increases to 10 KV, 15.75 KV approx. on manual / auto excitation control, respectively.
• RAISE generator excitation manually, to raise gen. voltage.• CHECK all the generator voltages (phase to phase).• All the three phases should read equal voltages
April 26, 2023 PMI Revision 00 20
Synchronisation• SWITCH-ON the synchroscope to CHECK mode.• IN-COMING/RUNNING voltages and frequencies start
showing on their Corresponding meters.• Alternatively synchroscope is put on Check mode and auto
synchroniser can be switched on.• Synchroscope needle starts rotating at a rate proportional to
difference between the generator and grid frequencies.• ADJUST turbine speed reference to match generator freq
with the grid (running).• ADJUST generator excitation to match the gen. voltage with
that of grid.• As synchroscope needle comes to 11'O clock position
(clockwise), the green CHECK lamp comes on & the red lamp goes off. At 12' O clock position the check lamp goes off and red lamp comes on again.
April 26, 2023 PMI Revision 00 21
SynchronisationWhen the voltage and frequency match, the synchroscope will
move very slowly in the clockwise direction. This position shows that:
i) Phase sequence of generated voltage and system voltage is same.
ii) Effective values of both the voltage are same. iii) Frequency of both the system and the incoming m/c is
same. • CLOSE the generator breaker when the check lamp is green.• ''Generator motoring'' alarm comes on. • INCREASE Starting Device to 100%.• RAISE speed reference slightly to increase Gen load, immediately after
closing the generator breaker.• Turbine load increases to 20 MW approximately. ''Speed controller''
transfers to 'Load controller'' after some time delay.
April 26, 2023 PMI Revision 00 22
Synchronisation• Gen. voltage and P.F., will be maintained by AVR if the
excitation mode is on "Auto", otherwise, maintain Gen. voltage and PF by varying the field rheostat from the Gen. control desk. If excitation mode is on manual, then change over to "Auto" mode after matching the parameters.
• Slowly raise the load on Generator upto 80 MW (Follow the guide lines given for loading the machine). Now the voltage and power factor will be maintained by the automatic voltage regulator (AVR).
April 26, 2023 PMI Revision 00 23
Unit Supply Changeover From Station To UAT
• Check that the unit auxiliary supply incoming breakers are racked in service position, springs are charged and "Local/Remote" switches are on "Remote" position.
• SWITCH-ON synchroscope to CHECK mode.• Synchroscope green lamp comes on after the two voltages
are matching• CLOSE UAT (A/B) incomer to Unit bus.• ''Unit/Station transformers paralleled'' annunciation comes
on.• Immediately OPEN the station breaker.
April 26, 2023 PMI Revision 00 24
LP HEATERS CHARGINGCHECK these conditions are satisfied before charging the LP
heaters.• Generator load is at least 40 MW.• All LP heaters are CHARGED from waterside and their bypass
valves are closed.• All LP heaters airline to condenser, are OPEN.• All pneumatic drip valves are OPERATIONAL & on REMOTE.• OPEN LPH-1 Extraction steam block valve ES-1.• Condensate temperature across LPH starts rising.• OPEN LPH-2 extraction block valve ES-2.• Associated line drain valve starts closing after the extraction block
valve opens 100%. • LPH-2 alternate drain to condenser starts closing.• LPH-2 normal drain valve starts modulating to maintain the level.
OPEN LPH-3 extraction block valve ES-3.
April 26, 2023 PMI Revision 00 25
April 26, 2023 PMI Revision 00 26
HP HEATERS CHARGING• CHECK before charging the HP Heaters:• Unit load is more than 120 MW.• HPHs water side inlet/outlet valves OPEN and individual bypass valve
are CLOSED.• HPHs group bypass valves are IN-SERVICE position and "HPHs
bypassed" alarm is NOT On.• All HPHs shell drains are OPEN.• All HPHs airlines to condenser isolating valves are open.• OPEN HPH-5 extr. steam block vlv ES-5.• After ES-5 is open, extr. line drain DW-73 closes.• HPH-5 alternate drain to condenser HD-31 closes• HPH-5 normal drain to D/A starts modulating to maintain the level.• Feed water temp after HPH-5 starts increasing.• Similarly charge HPH-6 and maintain the drip level.• Put drip level control on Auto.
April 26, 2023 PMI Revision 00 27
April 26, 2023 PMI Revision 00 28
Capability Curve
April 26, 2023 PMI Revision 00 29
LOAD RAISING• Increase the firing rate in the boiler as per the
TSE margin and load schedule.
April 26, 2023 PMI Revision 00 30
THANK YOU