generator & transformer protection
DESCRIPTION
PPT FOR 500MW GT PROTECTIONTRANSCRIPT
![Page 1: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/1.jpg)
Welcome to presentationWelcome to presentationonon
GENERATOR & TRANSFORMER GENERATOR & TRANSFORMER PROTECTIONPROTECTION
ELECTRICAL MAINTENANCE DEPARTMENTELECTRICAL MAINTENANCE DEPARTMENT
BYBY
K JACOB K JACOB JOSEJOSE
![Page 2: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/2.jpg)
CLASSES OF PROTECTIONCLASSES OF PROTECTION
•CLASS A1CLASS A1
•CLASS A2CLASS A2
•CLASS BCLASS B
•CLASS CCLASS C
![Page 3: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/3.jpg)
GROUPS OF PROTECTIONGROUPS OF PROTECTION
• Group-1 – Group-1 – DC source 1 from 1/2 FA DC source 1 from 1/2 FA section-1section-1
• Group-2 – Group-2 – DC source 2 from 1/2 FA DC source 2 from 1/2 FA section-2section-2
• In case of any In case of any DC supply failureDC supply failure in GRP in GRP inform Electrical Maintenance inform Electrical Maintenance immediatelyimmediately
![Page 4: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/4.jpg)
CLASS A1CLASS A1
CAUSES OF CLASS A1CAUSES OF CLASS A1
1. GT & UT PROTECTIONS1. GT & UT PROTECTIONS
2. GENERATOR BACKUP PROTECTION2. GENERATOR BACKUP PROTECTION
3. OTHER BACKUP PROTECTIONS3. OTHER BACKUP PROTECTIONS
![Page 5: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/5.jpg)
CLASS A1 – CAUSES – CLASS A1 – CAUSES – TRANSFORMER PROTECTIONSTRANSFORMER PROTECTIONS
TRANSFORMER PROTECTIONS-MECHANICALTRANSFORMER PROTECTIONS-MECHANICAL
• PRVPRV• BUCHHOLZ RELAYBUCHHOLZ RELAY• SUDDEN PRESSURE RELAYSUDDEN PRESSURE RELAY• FIRE PROTECTIONFIRE PROTECTION• UT OLTC SUDDEN PRESSURE RELAYUT OLTC SUDDEN PRESSURE RELAY
Note: UT A/B WTI/OTI will trip the Note: UT A/B WTI/OTI will trip the corresponding incomer from the transformer corresponding incomer from the transformer and change over to Standby Trf.and change over to Standby Trf.
![Page 6: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/6.jpg)
CLASS A1 – CAUSES – CLASS A1 – CAUSES – TRANSFORMER PROTECTIONSTRANSFORMER PROTECTIONS
TRANSFORMER PROTECTIONS-ELECTRICALTRANSFORMER PROTECTIONS-ELECTRICAL
• DIFFERENTIAL PROTECTION(GT/UT) – 87GT/87UTDIFFERENTIAL PROTECTION(GT/UT) – 87GT/87UT• GT HV WINDING + O/H LINE DIFFERENTIAL-87HVGT HV WINDING + O/H LINE DIFFERENTIAL-87HV• RESTRICTED EARTH FAULT (UT’s only)87NUT A/BRESTRICTED EARTH FAULT (UT’s only)87NUT A/B• STANDBY EARTH FAULT (GT only)-51NGTSTANDBY EARTH FAULT (GT only)-51NGT• OVERCURRENT PROTECTION (UT’s only)-51UT A/BOVERCURRENT PROTECTION (UT’s only)-51UT A/B• BACKUP EARTH FAULT (UT’s only)-51 NUT A/BBACKUP EARTH FAULT (UT’s only)-51 NUT A/B• GT OVERFLUXING – 99GTGT OVERFLUXING – 99GT• EARTH FAULT BEYOND GCB – 64GTEARTH FAULT BEYOND GCB – 64GT• GT + O/H LINE DIFFERENTIAL – 87TLGT + O/H LINE DIFFERENTIAL – 87TL
![Page 7: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/7.jpg)
CLASS A1 – CAUSES – BACKUP CLASS A1 – CAUSES – BACKUP PROTECTIONS FOR PROTECTIONS FOR GENERATORGENERATOR BACKUP PROTECTIONS FOR BACKUP PROTECTIONS FOR
GENERATORGENERATOR
• GENERATOR LBB (For GCB) – 50GLBBGENERATOR LBB (For GCB) – 50GLBB
• GENERATOR BACKUP IMPEDANCE – GENERATOR BACKUP IMPEDANCE – 21G21G
• DEAD MACHINE RELAY – 50GDMDEAD MACHINE RELAY – 50GDM
![Page 8: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/8.jpg)
CLASS A1 – CAUSES – OTHER CLASS A1 – CAUSES – OTHER BACKUP PROTECTIONSBACKUP PROTECTIONS
• SWITCHYARD TEE DIFFERENTIAL – SWITCHYARD TEE DIFFERENTIAL – 87TTIGX/87TT2GX87TTIGX/87TT2GX
• 400 KV BREAKER LBB – X52Z400 KV BREAKER LBB – X52Z (8-52/9-52/13-52/14-52)(8-52/9-52/13-52/14-52)
• 400KV BREAKER POLE DISCREPENCY -400KV BREAKER POLE DISCREPENCY -X52PDXX52PDX
(8-52/9-52/13-52/14-52) – DEFEATED(8-52/9-52/13-52/14-52) – DEFEATED
![Page 9: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/9.jpg)
CLASS A1 - ACTIONSCLASS A1 - ACTIONS
CLASS A1 CAUSES TRIPPING OFCLASS A1 CAUSES TRIPPING OF
• BOTH 400KV BREAKERS OF THE UNITBOTH 400KV BREAKERS OF THE UNIT
• GCBGCB
• FIELD BREAKERFIELD BREAKER
• STEAM TURBINESTEAM TURBINE
• UNIT TRANSFORMER INCOMERS – BA/BBUNIT TRANSFORMER INCOMERS – BA/BB
![Page 10: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/10.jpg)
CLASS A2 - CAUSESCLASS A2 - CAUSES
GENERATOR PROTECTIONSGENERATOR PROTECTIONS
• DIFFERENTIAL – 87G1/87G2DIFFERENTIAL – 87G1/87G2
• OVERVOLTAGE – 59G1OVERVOLTAGE – 59G1
• 95% EARTH FAULT -64G195% EARTH FAULT -64G1
• INTERTURN FAULT – 64GITINTERTURN FAULT – 64GIT
• OVERFLUXING – 99GOVERFLUXING – 99G
• NEGATIVE PHASE SEQUENCE – 46GNEGATIVE PHASE SEQUENCE – 46G
• LOW FORWARD POWER – 30sec – 37G1/2LOW FORWARD POWER – 30sec – 37G1/2
.. Contd... Contd.
![Page 11: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/11.jpg)
CLASS A2 - CAUSESCLASS A2 - CAUSES
GENERATOR PROTECTIONSGENERATOR PROTECTIONS
• POLE SLIPPING – 98GPOLE SLIPPING – 98G
• FIELD FAILURE – 40 G1/2FIELD FAILURE – 40 G1/2
..contd...contd.
![Page 12: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/12.jpg)
CLASS A2 - CAUSESCLASS A2 - CAUSES
SIEMENS MULTIFUNCTION RELAY – SIEMENS MULTIFUNCTION RELAY – 96G96G
• 100% STATOR EARTH FAULT100% STATOR EARTH FAULT
• ROTOR EARTH FAULTROTOR EARTH FAULT
• OVER VOLTAGEOVER VOLTAGE
![Page 13: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/13.jpg)
CLASS A2 - ACTIONSCLASS A2 - ACTIONS
CLASS A2 CAUSES TRIPPING OF CLASS A2 CAUSES TRIPPING OF
• GCBGCB
• FIELD BREAKERFIELD BREAKER
• STEAM TURBINESTEAM TURBINE
• UT INCOMER (if both 400kV breakers UT INCOMER (if both 400kV breakers are in tripped condition)are in tripped condition)
![Page 14: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/14.jpg)
CLASS B PROTECTIONCLASS B PROTECTION CLASS B – GENERATOR TRIP FROM TURBINE CLASS B – GENERATOR TRIP FROM TURBINE
TRIPTRIP
THIS IS ACHIEVED THROUGH LOW THIS IS ACHIEVED THROUGH LOW FORWARD POWER RELAY – 2 SEC DELAY- FORWARD POWER RELAY – 2 SEC DELAY- 37 G1/237 G1/2
NEED FOR CLASS B TRIPNEED FOR CLASS B TRIP
PROTECTION OF TURBINE FROM PROTECTION OF TURBINE FROM OVERHEATINGOVERHEATING
![Page 15: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/15.jpg)
CLASS B - ACTIONSCLASS B - ACTIONS
CLASS B CAUSES TRIPPING OF THE CLASS B CAUSES TRIPPING OF THE FOLLOWINGFOLLOWING
• GCBGCB• FIELD BREAKERFIELD BREAKER
(i.e. GT & UT will still be in charged (i.e. GT & UT will still be in charged condition from 400kV side – GRID)condition from 400kV side – GRID)
![Page 16: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/16.jpg)
CLASS C PROTECTION - CLASS C PROTECTION - CAUSESCAUSES
CLASS C IS CAUSED ONLY BY – CLASS C IS CAUSED ONLY BY –
UNDERFREQUENCY- UNDERFREQUENCY- 81G/96G81G/96G
(GRID COLLAPSE)(GRID COLLAPSE)
Presently connected to Class B at 45Hz.Presently connected to Class B at 45Hz.
![Page 17: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/17.jpg)
CLASS C PROTECTION - CLASS C PROTECTION - ACTIONSACTIONS
CLASS C CAUSES TRIPPING OFCLASS C CAUSES TRIPPING OF
• BOTH 400KV BREAKERSBOTH 400KV BREAKERS
(i.e. Unit will come on house load)(i.e. Unit will come on house load)
![Page 18: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/18.jpg)
ACTIONS IF CLASS A1 TRIP ACTIONS IF CLASS A1 TRIP OCCURSOCCURS
THE FOLLOWING ACTIONS ARE THE FOLLOWING ACTIONS ARE NECESSARYNECESSARY
• Restore unit supply if auto changeover Restore unit supply if auto changeover from standby trf. does not take placefrom standby trf. does not take place
• Ensure DG set availabilityEnsure DG set availability
• Inform Electrical MaintenanceInform Electrical Maintenance
![Page 19: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/19.jpg)
ACTIONS IF CLASS A2 ACTIONS IF CLASS A2 OCCURSOCCURS
THE FOLLOWING ACTIONS ARE THE FOLLOWING ACTIONS ARE NECESSAYNECESSAY
• Ensure unit supplies are healthyEnsure unit supplies are healthy
• Inform Electrical MaintenanceInform Electrical Maintenance
![Page 20: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/20.jpg)
CLASS A2 – LOW FORWARD CLASS A2 – LOW FORWARD RELAYRELAY
THE FOLLOWING SEQUENCE OF THE FOLLOWING SEQUENCE OF EVENTS OCCURSEVENTS OCCURS
• CLASS A2 TRIP – TRIP TO STEAM CLASS A2 TRIP – TRIP TO STEAM TURBINETURBINE
• AFTER TRUBINE TRIP – CLASS BAFTER TRUBINE TRIP – CLASS B
![Page 21: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/21.jpg)
CLASS A2 – LOW FORWARD CLASS A2 – LOW FORWARD RELAYRELAY
RESTARTINGRESTARTINGTHE FOLLOWING SEQUENCE OF EVENTS THE FOLLOWING SEQUENCE OF EVENTS
MUST BE FOLLOWEDMUST BE FOLLOWED
• RESET BOTH CLASS A2 TRIP RELAYSRESET BOTH CLASS A2 TRIP RELAYS• RESET STEAM TURBINE TRIPRESET STEAM TURBINE TRIP• RESET BOTH CLASS B TRIP RELAYSRESET BOTH CLASS B TRIP RELAYS• SYNCHRONISE USNIG GCBSYNCHRONISE USNIG GCB
Note: Reset trip relays only when Note: Reset trip relays only when starting to rollstarting to roll
![Page 22: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/22.jpg)
CLASS B TRIP - RESTARTINGCLASS B TRIP - RESTARTING
THE FOLLOWING SEQUENCE OF ACTIONS THE FOLLOWING SEQUENCE OF ACTIONS MUST BE FOLLOWEDMUST BE FOLLOWED
• RESET STEAM TURBINE RESET STEAM TURBINE • RESET BOTH CLASS B TRIP RELAYSRESET BOTH CLASS B TRIP RELAYS• SYNCHRONISE UNING GCBSYNCHRONISE UNING GCB
Note: Reset trip relays only when Note: Reset trip relays only when starting to rollstarting to roll
![Page 23: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/23.jpg)
CLASS C TRIP - ACTIONSCLASS C TRIP - ACTIONS
• Ensure unit has come on HOUSE Ensure unit has come on HOUSE LOAD and stabilizedLOAD and stabilized
• Ensure availability of DG setEnsure availability of DG set
• Inform Electrical MaintenanceInform Electrical Maintenance
![Page 24: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/24.jpg)
CLASS C - RESTARTINGCLASS C - RESTARTING
THE FOLLOWING SEQUENCE OF THE FOLLOWING SEQUENCE OF ACTIONS MUST BE FOLLOWEDACTIONS MUST BE FOLLOWED
• Energise 400KV switchyardEnergise 400KV switchyard
• After getting concurrence from After getting concurrence from SRLDC synchronise the unit using SRLDC synchronise the unit using 400KV breakers 400KV breakers
![Page 25: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/25.jpg)
STARTUP/TRIPPING RELAY-STARTUP/TRIPPING RELAY-RESETTINGRESETTING
• Just before rolling only, reset the trip Just before rolling only, reset the trip relaysrelays
• After excitation, in case any of the After excitation, in case any of the fuse fail relays/50GDM flag has fallen fuse fail relays/50GDM flag has fallen reset themreset them
• After synchronisation, see that no After synchronisation, see that no relays have acted. relays have acted.
• If the Low forward power relay LED If the Low forward power relay LED has come, it should be reset.has come, it should be reset.
![Page 26: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/26.jpg)
THANKYOUTHANKYOU
![Page 27: Generator & Transformer Protection](https://reader034.vdocuments.site/reader034/viewer/2022050702/55cf981d550346d03395ac0e/html5/thumbnails/27.jpg)
QUESTIONS QUESTIONS
PLEASEPLEASE