Generator protection

Generator Protection Training Package

• Trainer: Dr. Saeed Roostaee (Profile on Linkedin)
• Pre-recorded videos
• Supplementary Files
• The course is licensed and you need a Windows computer to view the videos
• Download this course: contact us or leave a comment on this post

Main course:

Part A: Introduction, review the generator construction and protection

• GA 01 (10 min, Dec 30, 2021): Cylindrical and salient pole rotors, generator connections, normal Operation, abnormal Conditions, generator protection, function of a protection System, generator grounding techniques, fault Current Behavior of a synchronous generator

• GA 02 (12 min, Dec 30, 2021): stator winding faults, field winding or rotor circuit faults, abnormal operating conditions, the object of the protection system, generator protective relaying technology, multifunction generator protection systems (MGPS), numerical relays, generator ANSI codes, IEEE Recommendations for different Generator protection functions, an overview of different generator relays from different manufactures (ABB, Schneider, SEL, Siemens)

• GA 03 (08 min, Dec 30, 2021): The review of REG 670 relay, the hardware structure of REG670, rearview and front view of REG670, main protection functions, backup protection functions, control & monitoring functions, REG670 templates (A20, B30, C30)

• GA 04 (18 min, Dec 30, 2021): REG670 configuration (online, offline)
• GA 05 (17 min, Dec 30, 2021): REG670 configuration (online, offline)
• GA 06 (10 min, Dec 30, 2021): injecting signals and monitoring in the REG670 signal monitoring, config binary outputs
• GA 07 (12 min, Dec 30, 2021): signal monitoring and troubleshooting technique
• GA 08 ( 22 min, Dec 30, 2021): config and testing of the inverse time overcurrent in REG670
• GA 09 (23 min, Dec 30, 2021): config and settings of the directional overcurrent in REG670
• GA 10 (06 min, Dec 30, 2021): testing of the directional in REG670
• GA 11 (10 min, Jan 20, 2022): theory of operation of synchronous AC Generator, typical generation systems, grounding strategies

Part B: Generator differential protection

• GB 01 (04 min, Jan 08, 2022): Review of the generator protection functions in Single line diagram
• GB 02 (03 min, Jan 08, 2022): Principal of differential protection function
• GB 03 (10 min, Jan 08, 2022): Configurations and parameters of the generator differential protection block
• GB 04 (01 min, Jan 20, 2022): phase differential element

Part C: Generator stator earth fault protection

• GC 01 (06 min, Jan 20, 2022): why stator earth fault protection, 59N, 27TN, 100 % stator earth fault protection?
• GC 02 (08 min, Jan 20, 2022): stator earth fault protection
• GC 03 (06 min, Jan 20, 2022): Configuration and parameter settings of the 100 stator earth fault function block

Part D: Generator Under excitation / Loss-of -Excitation (ANSI 40 ) protection

• GD 01 (03 min, Jan 20, 2022): causes of loss of field, generator capability curve, end region heating, steady-state stability limit, under excitation limiter
• GD 02 (08 min, Jan 20, 2022): Generator Capability Curve
• GD 03 (02 min, Jan 20, 2022): PQ plane and RX plane
• GD 04 (07 min, Jan 20, 2022): Impact of the generator loss of excitation
• GD 05 (04 min, Jan 20, 2022): generator loss of excitation protection
• GD 06 (05 min, Jan 20, 2022): Configuration and parameter settings of the loss of excitation function block

Part E: Generator Out of Step Protection (Pole Slip)

• GE 01 (01 min, Jan 20, 2022): generator loses synchronism or Out of-step or pole slip definition
• GE 02 (19 min, Jan 20, 2022): generator pole slip
• GE 03 (18 min, Jan 20, 2022): generator pole slip protection
• GE 04 (09 min, Jan 20, 2022): Configuration and parameter settings of the pole slip function block

Part F: Generator negative sequence protection

• GF 01 (03 min, Jan 29, 2022): Negative Sequence Protection (46)
• GF 02 (09 min, Jan 29, 2022):
• GF 03 (02 min, Jan 29, 2022): continuous and short-time unbalanced current capabilities

Part G: Generator low forward and Reverse Power (Anti-Motoring or Loss of Prime Mover protection)

• GG 01-03 (12 min, Jan 29, 2022): potential damages for each generator type

Part H: Generator Over-Under Frequency and Generator under-voltage protection

• GH 01 (06 min, Jan 29, 2022): Over-Under Frequency (81U, 81O)
• GH 02 (03 min, Jan 29, 2022): under-voltage protection (27, 59G)

Supplementary files:

Update December 22, 2021

1. Synchronous generator protection (.pdf)
2. Underimpedance protection ANSI 21B (.pdf)
3. Generator Overfluxing protection ANSI 24 (.pdf)
4. Generator Loss of field protection ANSI 40 (.pdf)
5. Inadvertent energization protection ANSI 50/27 (.pdf)
6. 100% stator earth fault protection ANSI 64G (.pdf)
7. Generator Pole slip protection ANSI 78PS (.pdf)
8. ABB generator protection e-book (.pdf)
9. Areva generator protection e-book (.pdf)
10. Protection against loss of excitation in generators (.pdf)
11. Loss-of-excitation Protection for Synchronous Generators (.pdf)
12. Application of Out-of-Step Blocking and Tripping Relays (.pdf)
13. Generating Station Protection (.pdf)
14. IEEE Guide for AC Generator Protection (.pdf)
15. Standard PRC Generator Frequency and Voltage Protective Relay Settings (.pdf)
16. REG216 Manual (.pdf)
17. REG316 Manual (.pdf)
18. Generator protection relay setting calculations (.pdf)
19. Generator protection (.pdf)
20. Protection of Synchronous Generators (.pdf)
21. IEEE Guide for Abnormal Frequency Protection for Power Generating Plants (.pdf)
22. IEEE Guide for AC Generator Protection (.pdf)
23. IEEE Guide for Generator Ground Protection (.pdf)
24. IEEE Guide for AC Generator Protection (.pdf)
25. A-C GENERATOR AND MOTOR PROTECTION (.pdf)
26. SIPROTEC Multi-Functional Generator Protection Relay 7UM61 (.pdf)
27. SEL-300G Generator Relay (.pdf)
28. SEL-700G Family of Generator and Intertie Protection Relays (.pdf)
29. G60 Generator Protection System (.pdf)
30. Generator protection REG670 (.pdf)
31. Sepam 2000 Generator (.pdf)
32. Generator Data Sheet (.pdf)
33. CT Performance in Differential Relay Circuits (.pdf)
34. Dynamic and Steady State Stability Limits (.pdf)
35. Swing Impedance Locus Calculation Using Excel (.pdf)
36. Generator Shaft Torsional Transients (.pdf)
37. Generator Normal Operations (.pdf)
38. Generator Short Circuit Calculations (.pdf)
39. Generator Differential Relay: 87G (.pdf)
40. Backup Fault Protection (.pdf)
41. Generator Ground Fault Protection (.pdf)
42. Unbalanced Current Protection (.pdf)
43. Motoring Protection (.pdf)
44. Overexcitation (.pdf)
45. Abnormal Frequency Protection (.pdf)
46. Minimum Excitation Limiter (.pdf)
47. Loss of Synchronism (.pdf)
48. Loss of Field Protection (.pdf)
49. Synchronization Protection (.pdf)
50. Accidental Energization Protection (.pdf)

Update Feb 02, 2022

REG670 excel spreadsheets (Revision01): Helpful excel file to set the REG670 parameters

Update March 15, 2022

1. Coordination of generator protection with generator excitation control and generator capability (.pdf)
2. Impact of excitation system on power system stability (.pdf)
3. Investigation on Generator Loss of Excitation Protection in Generator Protection Coordination (.pdf)
4. Generator capability curve (.pdf)
5. Impact of leading power factor loads on synchronous alternators (.pdf)
6. Synchronous Machines (.pdf)
7. Synchronous Generator Characteristics Curve (.pdf)

Note: This course will be updated over time, updates are free, and no extra charges.

Certificate of Completion

After activating the Generator Protection training pack on your system, we will issue your certificate for the course.

1. GP-1002: Click here to download
2. GP-1003: Click here to download
3. GP-1004: Click here to download
4. GP-1005: Click here to download
5. GP-1006: Click here to download
6. GP-1007: Click here to download
7. GP-1008: Click here to download
8. GP-1009: Click here to download
9. GP-1010: Click here to download
10. GP-1011: Click here to download
11. GP-1012: Click here to download
12. GP-1013: Click here to download
13. GP-1014: Click here to download
14. GP-1015: Click here to download
15. GP-1016: Click here to download
16. GP-1017: Click here to download
17. GP-1018: Click here to download
18. GP-1019: Click here to download
19. GP-1020: Click here to download
20. GP-1021: Click here to download
21. GP-1022: Click here to download
22. GP-1023: Click here to download

• 87G Generator Differential Protection
• 87T GSU Trans. Differential Protection
• 87GT Overall Differential Protection
• 40G Generator Field Failure Protection
• 78G Generator Pole Slipping Protection
• 50S, Generator Split phase overcurrent protection
• 46 Generator Negative Phase Sequence Protection
• 51V Generator Voltage-Dependent O/C Protection
• 49S Generator Stator Overload Protection
• 59G Generator Overvoltage Protection
• 21G Generator Underimpedance Protection
• 27G Generator Undervoltage Protection
• 32R Generator Reverse Power Protection
• 64S Generator 95%&100% Stator Earth Fault Protection
• 51/27 Generator Dead Machine Protection
• 64GB Generator Busbar Earth Fault Protection
• 64R Generator Rotor Earth Fault Protection
• 81O Generator Overfrequency Protection
• 81U Generator Underfrequency Protection
• 24G Generator Overflux Protection
• 47G Generator Fuse Failure Supervision
• 50/51ET Excitation Trans. Overcurrent Protection
• 49ET Excitation Trans. Overload Protection
• 51N-GSU Gen. Step-up Trans. Neutral Point OvercurrentProtection
• 64T GSU Trans. Restricted Earth Fault Protection
• 50/51T GSU Trans. Over Current Protection
• 50/51SST Station Service Trans. Over Current Protection
• …..

+

WHY GENERATOR PROTECTION?

• Unnecessary tripping of Generators is undesirable (production losses, black-out, startup time)
• Not tripping and damaging the machine would be expensive (to repair)

The fault current in the faulted generator does not stop when the Generator is tripped or the field breaker is tripped. The flux/energy stored in the field will continue to supply fault current for several seconds

• Generator differential
• Transformer differential
• Four-step overcurrent protection (DFT-based measurement)
• Four-step residual overcurrent protection
• Over/under voltage protection (DFT based measurement)
• Residual overvoltage protection
• Overexcitation protection
• General current and voltage protection
• Directional over/under power function
• …

• 21P Phase distance backup
• 51N Neutral time overcurrent
• 24 Volts per hertz
• 59N Neutral overvoltage
• 25 Synchrocheck
• 59P Phase overvoltage
• 27P Phase Undervoltage
• 59X Auxiliary overvoltage
• 27TN Third harmonic neutral Undervoltage
• 59_2 Negative-sequence overvoltage
• 27X Auxiliary Undervoltage
• 64F Field ground protection
• 32 Sensitive directional power
• 64S Sub-harmonic stator ground protection
• 40 Loss of excitation
• 64TN 100% stator ground
• 46 Generator unbalance
• 67_2 Negative-sequence directional overcurrent
• 49 Thermal overload protection (RTD)
• 67N Neutral directional overcurrent
• 50BF Breaker failure
• 67P Phase directional overcurrent
• 50G Ground instantaneous overcurrent
• 68 Power swing blocking
• 50N Neutral instantaneous overcurrent
• 78 Out-of-step protection
• 50P Phase instantaneous overcurrent
• 81O Overfrequency
• 50SP Split phase protection
• 81R Rate of change of frequency
• 50/27 Accidental energization
• 81U Underfrequency
• 51G Ground time overcurrent
• 87RGF Restricted ground fault
• 51PV Phase time overcurrent with voltage restraint
• 87S Stator differential
• …

Basic Generator Protection Features

• Ground differential
• Sensitive restricted earth fault
• Thermal overload
• Negative-sequence
• Residual-ground and neutral-ground overcurrent elements
• Directional residual-ground
• Overcurrent elements
• Unbalance element
• Voltage-controlled, voltage-restrained time-overcurrent
• Breaker failure protection for three-pole breaker
• Under- and overvoltage
• Inverse-time over- and Undervoltage elements
• Loss-of-potential element
• Volts/hertz or overexcitation protection
• Directional power elements
• Loss-of-field
• Over- and under frequency protection
• Rate-of-change-of- frequency
• RTD protection
• …

Optional Generator Protection

• Generator synchronism check
• Synchronism-check under- and overvoltage
• Inverse-time over- and Undervoltage
• Out-of-step
• vector shift
• 100% stator ground protection
• …..