Disturbance Analysis for Power Systems

More than ninety case studies shed new light on power system phenomena and power system disturbances

Based on the author's four decades of experience, this book enables readers to implement systems in order to monitor and perform comprehensive analyses of power system disturbances. Most importantly, readers will discover the latest strategies and techniques needed to detect and resolve problems that could lead to blackouts to ensure the smooth operation and reliability of any power system.

Logically organized, Disturbance Analysis for Power Systems begins with an introduction to the power system disturbance analysis function and its implementation. The book then guides readers through the causes and modes of clearing of phase and ground faults occurring within power systems as well as power system phenomena and their impact on relay system performance. The next series of chapters presents more than ninety actual case studies that demonstrate how protection systems have performed in detecting and isolating power system disturbances in:

• Generators

• Transformers

• Overhead transmission lines

• Cable transmission line feeders

• Circuit breaker failures

Throughout these case studies, actual digital fault recording (DFR) records, oscillograms, and numerical relay fault records are presented and analyzed to demonstrate why power system disturbances happen and how the sequence of events are deduced. The final chapter of the book is dedicated to practice problems, encouraging readers to apply what they've learned to perform their own system disturbance analyses.

This book makes it possible for engineers, technicians, and power system operators to perform expert power system disturbance analyses using the latest tested and proven methods. Moreover, the book's many cases studies and practice problems make it ideal for students studying power systems.

Auteur

MOHAMED A. IBRAHIM, PE, is a registered Professional Engineer in New York State. He is a Fellow of the IEEE for his contributions to the field of protection and control. Dr. Ibrahim has held positions at Helwan University, Mansoura University, and Polytechnic Institue of New York University. He lectured at Auburn University and Washington State University. Dr. Ibrahim retired in 2004 as the director of protection and control at the New York Power Authority to become a consultant, forming his own company. He is the author or coauthor of twenty-five technical papers on computer relaying and protection areas.

Texte du rabat

More than ninety case studies shed new light on power system
phenomena and power system disturbances

Based on the author's four decades of experience, this book
enables readers to implement systems in order to monitor and
perform comprehensive analyses of power system disturbances. Most
importantly, readers will discover the latest strategies and
techniques needed to detect and resolve problems that could lead to
blackouts to ensure the smooth operation and reliability of any
power system.

Logically organized, Disturbance Analysis for Power Systems
begins with an introduction to the power system disturbance
analysis function and its implementation. The book then guides
readers through the causes and modes of clearing of phase and
ground faults occurring within power systems as well as power
system phenomena and their impact on relay system performance. The
next series of chapters presents more than ninety actual case
studies that demonstrate how protection systems have performed in
detecting and isolating power system disturbances in:

• Generators

• Transformers

• Overhead transmission lines

• Cable transmission line feeders

• Circuit breaker failures

Throughout these case studies, actual digital fault recording
(DFR) records, oscillograms, and numerical relay fault records are
presented and analyzed to demonstrate why power system disturbances
happen and how the sequence of events are deduced. The final
chapter of the book is dedicated to practice problems, encouraging
readers to apply what they've learned to perform their own system
disturbance analyses.

This book makes it possible for engineers, technicians, and
power system operators to perform expert power system disturbance
analyses using the latest tested and proven methods. Moreover, the
book's many cases studies and practice problems make it ideal for
students studying power systems.

Contenu

Preface xvii

1 Power System Disturbance Analysis Function 1

1.1 Analysis Function of Power System Disturbances 2

1.2 Objective of DFR Disturbance Analysis 4

1.3 Determination of Power System Equipment Health Through System Disturbance Analysis 5

1.4 Description of DFR Equipment 6

1.5 Information Required for the Analysis of System Disturbances 7

1.6 Signals to be Monitored by a Fault Recorder 8

1.7 DFR Trigger Settings of Monitored Voltages and Currents 10

1.8 DFR and Numerical Relay Sampling Rate and Frequency Response 11

1.9 Oscillography Fault Records Generated by Numerical Relaying 11

1.10 Integration and Coordination of Data Collected from Intelligent Electronic Devices 12

1.11 DFR Software Analysis Packages 12

1.12 Verification of DFR Accuracy in Monitoring Substation Ground Currents 21

1.13 Using DFR Records to Validate Power System Short-Circuit Study Models 24

1.14 COMTRADE Standard 31

2 Phenomena Related To System Faults and The Process of Clearing Faults From A Power System 33

2.1 Shunt Fault Types Occurring in a Power System 33

2.2 Classification of Shunt Faults 34

2.3 Types of Series Unbalance in a Power System 39

2.4 Causes of Disturbance in a Power System 39

2.5 Fault Incident Point 40

2.6 Symmetric and Asymmetric Fault Currents 41

2.7 Arc-Over or Flashover at the Voltage Peak 44

2.8 Evolving Faults 48

2.9 Simultaneous Faults 51

2.10 Solid or Bolted (RF¼0) Close-in Phase-to-Ground Faults 52

2.11 Sequential Clearing Leading to a Stub Fault that Shows a Solid (RF¼0) Remote Line-to-Ground Fault 53

2.12 Sequential Clearing Leading to a Stub Fault that Shows a Resistive Remote Line-to-Ground Fault 54

2.13 High-Resistance Tree Line-to-Ground Faults 56

2.14 High-Resistance Line-to-Ground Fault Confirming the Resistive Nature of the Fault Impedance When Fed from One Side Only (Stub) 58

2.15 Phase-to-Ground Faults on an Ungrounded System 59

2.16 Current in Unfaulted Phases During Line-to-Ground Faults 60

2.17 Line-to-Ground Fault on the Grounded-Wye (GY) Side of a Delta/GY Transformer 63

2.18 Line-to-Line Fault on the Grounded-Wye Side of a Delta/GY Transformer 65

2.19 Line-to-Line Fault on the Delta Side of a Delta/GY Transformer with No Source Connected to the Delta Winding 66

2.20 Subcycle Relay Operating Time During an EHV Double-Phase-to-Ground Fault 68

2.21 Self-Clearing of a C-g Fault Inside an Oil Circuit Breaker Tank 69

2.22 Self-Clearing of a B-g Fault Caused by a Line Insulator Flashover 70

2.23 Delayed Clearing of a Pilot Scheme Due to a Delayed Communication Signal 71

2.24 Sequential Clearing of a Line-to-Ground Fault 72

2.25 Step-Distance Clearing of an L-g Fault 74

2.26 Ground Fault Clearing in Steps by an Instantaneous Ground Element at One End and a Ground Time Overcurrent Element at the Other End 76

2.27 Ground Fault Clearing by Remote Backup Following the Failures of Both Primary and Local Backup (Breaker Failure) Protection Systems 78

2.28 Breaker Failure Clearing of a Line-to-Ground Fault 79

2.29 Determination of the Fault Incident Point and Classification of Faults Using a Comparison Method 81

3 Power System Phenomena and Their Impact On Relay System Performance 85

3.1 Power System Oscillations Leading to Simultaneous Tripping of Both Ends of a Transmission Line …