Protective Relaying for Power Generation Systems
Features
Summary
Power outages have considerable social and economic impacts, and effective protection schemes are crucial to avoiding them. While most textbooks focus on the transmission and distribution aspects of protective relays, Protective Relaying for Power Generation Systems is the first to focus on protection of motors and generators from a power generation perspective. It also includes workbook constructions that allow students to perform protection-related calculations in Mathcad® and Excel®.
This text provides both a general overview and in-depth discussion of each topic, making it easy to tailor the material to students' needs. It also covers topics not found in other texts on the subject, including detailed time decrement generator fault calculations and minimum excitation limit. The author clearly explains the potential for damage and damaging mechanisms related to each protection function and includes thorough derivations of complex system interactions. Such derivations underlie the various rule-of-thumb setting criteria, provide insight into why the rules-of-thumb work and when they are not appropriate, and are useful for post-incident analysis. The book's flexible approach combines theoretical discussions with example settings that offer quick how-to information.
Protective Relaying for Power Generation Systems integrates fundamental knowledge with practical tools to ensure students have a thorough understanding of protection schemes and issues that arise during or after abnormal operation.
Table of Contents
GENERATOR NORMAL OPERATIONS
The Sample System
Generator Capability
Voltage Limitations
System Limitations
Generator Capability Variations with Voltage
Excitation System
References
GENERATOR SHORT CIRCUIT CALCULATIONS
Introduction
Short-Circuit Current Characteristics
Generator Internal Magnetics
Generator Magnetic Structures
Generator Constants
Fault Current Calculations
Voltage Regulator
Practical Shortcuts
Short Circuit Calculation Example
References
GENERATOR DIFFERENTIAL RELAY: 87G
Introduction
Ideal Differential Relay
Practical Considerations
Percentage Differential Relay
Relay Characteristics
Minimum Operating Current Setting
Slope Setting
Sample System Differential Relay Settings
CT Saturation
Stabilizing Resistor
Balancing Burden
Time Delay
Frequency Response
References
BACKUP FAULT PROTECTION
Purpose and Implementation
Voltage Supervised Overcurrent Relays
Distance Relays
References
GENERATOR GROUND FAULT PROTECTION
Introduction
Generator Grounding Considerations
Methods of Grounding
Ground Fault Protection
References
UNBALANCED CURRENT PROTECTION
Introduction
What is Negative-Sequence Current?
Effects of Negative-Sequence Current
Generator Negative-Sequence Capability
Sources of Negative-Sequence Current
In-Service (I2)^2t Duty Versus Standards
Unbalanced Current Protection
Negative-Sequence Relay Settings
References
MOTORING PROTECTION
Introduction
Effects of Motoring
Protection
Sequential Trip Logic
Backup Protection
Setting Device 32
Applying Reversed Power Relay on the Sample System
References
FIELD WINDING PROTECTION
Field Ground Protection
Field Overcurrent Protection
Settings for Field Overcurrent Overvoltage Relays
Applying Field OC Protection on the Sample System
References
OVEREXCITATION
Introduction
Causes of Overexcitation
Damage
V/Hz Limits
Protection
Settings
Differential Relay Response to Overexcitation
Application of V/Hz Protection on the Sample System
References
ABNORMAL FREQUENCY PROTECTION
Introduction
Effect on Generator
Steam Turbines
Combustion Turbines
Hydro Generators
Excitation System
Protection and Settings
References
MINIMUM EXCITATION LIMITER
Overview of the Minimum Excitation Limiter Application
Setting Criteria Background
Setting Criteria
Steady State and Dynamic Stability Considerations
Generator Leading VAR Capability
Coordination with the LOF Relay
System Stability Limits
MEL Protective Characteristic
MEL Dynamic Performance
MEL Application on the Sample System
References
LOSS OF SYNCHRONISM
Introduction
Turbine Generator Damage
Transient Stability
Out-of-Step Protection
Classical Swing Impedance Characteristic
Dynamic Swing Representation
Dynamic Swing Calculations
Setting Consideration
Out-of-Step Relay: Device 78
Setting Out-of-Step on Sample System
References
LOSS OF FIELD PROTECTION
General
System Impact
Generator Damage
Loss of Field Protection: Device 40
Distance Relay Schemes
Other Causes for LOF Relay Operations
LOF Relays During System Disturbances
Special Considerations for Hydro Units
Application of the LOF on the Sample System
References
SYNCHRONIZATION PROTECTION
Introduction
Damage
Synchronizing Methods
Synchronism Check Relays (Device 25)
Automatic Synchronizer (Device 25A)
Slow Breaker Protection
Settings
Synchronizing Equipment on the Sample System
References
ACCIDENTAL ENERGIZATION PROTECTION
Introduction
Generator State at Energization
Inadvertent Energization
Breaker Flashover
Dynamic Analysis of Three-Phase Energization from Standstill
Generator Damage
Turbine Damage
Energization Protection
Protection Provided by Native Schemes
Dedicated Energization Protection
Applying Energization Protection on the Sample System
References
MOTOR PROTECTION
Introduction
Motor Characteristics And Representation
Motor Ratings
Motor Characteristics
Motor Applications
Motor Starting
Mechanic System Considerations
Pump Characteristics
Motor Overload Protection
Multifunction Microprocessor Relays
Transient Current Evaluation
Special Schemes for Difficult Starts
Direct Temperature Measurement
Phase Fault Protection
Ground Fault Protection
Phase Unbalanced Protection
Sample Setting Calculations
References
APPENDIX A: SWING IMPEDANCE LOCUS CALCULATION USING EXCEL®
APPENDIX B
APPENDIX C
APPENDIX D
APPENDIX E
APPENDIX F
INDEX
Editorial Reviews
"Protective Relaying for Power Generation Systems by Donald Reimert presents a comprehensive review of the many protective and operating aspects associated with generators. It is almost encyclopedic in its discussions of the many elements and should be a valuable addition to every power engineer's reference library. This book, with 16 chapters and five appendices, arguably may be the most comprehensive single volume on generator and motor protection on the market. …the depth of analysis, the data presented, and the qualitative discussion of all of the aspects involved in generator protection add a dimension not available in any single text."
—Stanley H. Horowitz, IEEE Power & Energy Magazine, Sept/Oct, 2006
"…covers a wide range of topics and can help the reader to achieve basic understanding or deep knowledge of generator and motor protection, thus meeting the needs of both students and professionals… The author… has worked for more than 35 years in the design not only of generator and motor protection systems, but also substation, transmission, and distribution facilities. His system planning experience as well as the preparation and teaching of different protection related courses at the University of Wisconsin-Milwaukee allow him to present the material in the book in a clear and practical manner."
—PAC World Magazine
Downloads Updates
| Resource | OS Platform | Updated | Description | Instructions |
|---|---|---|---|---|
| APP_B_CT Performance_Diff.mcd | Cross Platform | February 17, 2006 | ||
| APP_C_Dynamic_Steady_Stability.xls | Cross Platform | February 17, 2006 | ||
| APP_D_Swing4.xls | Cross Platform | February 17, 2006 | ||
| APP_E_Torsion.mcd | Cross Platform | February 17, 2006 |
