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Prévia do material em texto

Contents 
Foreword 
Chapter authors 
Editorial panel 
Protection symbols used in circuit diagrams 
1 Role of protection M.Kaufmann and G.S.H.Jarrett 
1.1 Introduction 
1.1.1 General considerations 
1.1.2 Role of protection in a power station 
1.2 System and substation layout 
1.2.1 System layout 
1.2.2 Substation layout (electrical) 
1.2.3 Current transformer location 
1.3 System earthing 
1.3.1 Neutral-earthing methods 
1.3.2 Special cases of resistance earthing 
1.4 Faults 
1.4.1 
1.4.2 
1.4.3 
Faults and other abnormalities 
Nature and causes of faults 
Fault statistics 
1.5 Basic terms used in protection 
1.6 Necessity for back-up protection 
1.7 Economic considerations 
1.7. I General 
1.7.2 Distribution systems 
1.7.3 Transmission systems 
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XVIII 
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Conten~ 
1,8 Bibliography 
2 Protection principles and components H.S.Petch and J.Rushton 
2,1 Fundamental principles 
2.1.1 Methods of discrimination 
2.1.2 Derivation of relaying quantities 
2.1.3 Combined overcurrent and earth fault relays 
2.1.4 Derivation of a representative single-phase quantity from a 
three-phase system 
2,2 Components of protection 
2,2.1 
2,2.2 
2.2.3 
2.2.4 
2.2.5 
2.2.6 
2.2.7 
2.2.8 
2.2.9 
2,2.10 
Relays 
Current transformers 
Voltage transforming devices 
Capacitor dividers 
H.F. capacitor couplers 
Line traps 
Circuit-breakers 
Tripping and other auxiliary supplies 
Fuses, small wiring, terminals and test links 
Pilot circuits 
2,3 Consideration of the protection problem 
2,4 Bibliography 
3 Fault calculations J.H.Naylor 
3,1 Introduction 
3.1.1 Purpose of fault calculation 
3.1.2 Types of fault 
3.1.3 Factors affecting fault severity 
3.1.4 Methods of fault calculation 
3,2 Basic principles of network analysis 
3.2.1 Fundamental network laws 
3.2.2 Mesh-current analysis 
3.2.3 Nodal-voltage analysis 
3,2.4 Application of mesh-current and nodal-voltage analysis 
3,2.5 Network theorems and reduction formulas 
3,3 Calculations of balanced fault conditions 
3,3.1 
3.3.2 
3.3.3 
3.3.4 
3.3.5 
3.3.6 
3,3.7 
3,3.8 
3.3.9 
3.3.10 
Single-phase representation 
Use of a common voltage base 
Representation of nominal-ratio transformer circuits 
Representation of off-nominal-ratio transformer circuits 
Transformer phase-shifts 
Representation of synchronous machines 
Use of per-unit and per-cent values 
Fault-calculation procedure 
Example 1 
Example 2 
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Contenta 
3.4 Calculation of unbalanced fault conditions 
3.4.1 
3.4.2 
3.4.3 
3A.4 
3.4.5 
3.4.6 
3.4.7 
3.4.8 
3.4.9 
3.4.10 
3.4.11 
3.4.12 
Symmetrical components 
Phase-sequence networks and impedances 
Phase-sequence equivalent circuits 
Analysis of short-circuit conditions 
Effect of fault impedance 
Analysis of open-circuit conditions 
Transformer phase-shifts 
Fauit-calculation procedure 
Example 3 
Example 4 
Example 5 
Example 6 
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3.5 Calculation of simuRaneons fault conditions 
3.5.1 Sequence networks 
3.5.2 Cross-country earth-fauR 
3.5.3 Sequence network interconnections 
3.5.4 Example 7 
3.5.5 Example 8 
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3.6 Practical network analysis 
3.6.1 Network analysers 
3.6.1.1 A.C.analyser 
3.6.1.2 D.C. analyser 
3.6.2 Digital-computer analysis 
3.6.3 Transient analysts 
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3.7 
3.8 
Winding faults 
3.7.1 General considerations 
3.7.2 Generator-winding faults 
3.7.3 Transformer-winding faults 
Appendixes 
3.8.1 Representation of off-nominal-ratio transformers 
3.8.2 Effects of overhead-fine asymmetry 
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3.9 Bibliography 245 
4 
4.1 
4.2 
Protective transformers N.Ashton and EJ.MeUor 
General 
4. I. I Introduction 
4. 1.2 Basic transformer principles 
Steady-state theory of current transformers 
4.2.1 
4.2.2 
4.2.3 
4.2.4 
4.2.5 
4.2.6 
Equivalent circuit, vector diagram, errors 
Influence of the core, magnetic materials, and 
magnetisation curves 
Single-turn primary current transformers 
Flux leakage 
Balancing windings and eddy-current shielding 
Open-circuit secondary voltage 
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Contents 
4.2.7 
4.2.8 
Secondary currents, borders and connecting lead resistance 
Test windings 
4.3 Current transformers for protection 
4.4 
4.3.1 
4,3.2 
4,3.3 
4,3.4 
4.3.5 
4.3.6 
4.3.7 
Saturation of the core and ratio on overcurrents. BS 3938 
Trip-coil operation 
Overcurrent-relay operation 
Earth-fault relays with inverse-time characteristics 
Relay settings and primary operating currents 
Current transformers for balanced differential protective 
schemes 
Simple transient-state theory 
Construction of current transformers 
4.4.1 Basic types 
4.4.2 Forms of cores 
4.4.3 Windings and insulation 
4.4.4 High-voltage current transformers 
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4.S Testing of current transformers 
4.5.1 Error measurements 
4.5.2 Turns ratio tests 
4.5.3 Exciting current 
4.5.4 Current transformers for balanced differential protective 
schemes 
4.5.5 Polarity 
4.5.6 Insulation tests 
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4.6 Voltage-transformer theory 
4.6.1 Electromagnetic-type voltage transformers 
4.6.2 Capacitor-type voltage transformers 
4.6.3 Burdens and lead resistances 
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4.7 Voltage transformers for protection 
4.7.1 Electromagnetic type, categories, residual voltages 
4.7.2 Capacitor type 
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4,8 Construction of voltage transformers 
4.8.1 Electromagnetic type 
4.8.2 Cascade type 
4.8.3 Capacitor type 
4.8.4 Capacitor divider voltage sensor 
4,8.5 Voltage transformers for SF6 metalclad switchgear 
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4.9 Fusing and protection of voltage transformers 304 
4,10 Testing of voltage transformers 
4,10.1 Error measurements 
4.10.2 Core losses 
4.10.3 Insulation tests 
4.10.4 Polarity 
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4,11 Bibliography 306 
Contents 
5 Fuses H. W. Turner and C Turner 307 
5.1 
5.2 
Introduction 
5.1.1 Definition of a fuse 
5.1.2 Definition of a fuselink 
5.1.3 Categories of fuse 
Fuse design 
5.2.1 Powder-filled cartridge fuse 
5.2.1.1 High-voltage powder-filled fuses 
5.2.2 Miniature fuselink 
5.2.3 Semi-enclosed fuse 
5.2.4 Expulsion fuse 
5.2.5 Other fuse developments 
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5.3 
5.4 
5.5 
Mechanism of fuse operation 
5.3.1 Operation on small overcurrents 
5.3.2 Operation on large overcurrents 
5.3,3 Operation on intermediate overcurrents 
5.3.4 Operation on pulsed loading 
5.3.5 Fulgarite (roping) 
5.3.6 Typical oscillograms 
Peak arc voltage 
Time/current characteristic and factors affecting it 
5.5.1 Definitions related to the operation of fuses at the small 
overcurrent region of the time/current characteristic and 
the assignment of current rating 
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5.6 Discrimination 
5.6.1 Discrimination between fuselinks 
5.6.2 Discrimination between h.v. and l.v. fuses and circuit- 
breaking devices 
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5.7 Testing of fuses 
5.7.1 Fuse testing on a.c. 
5.7.1.1 Breaking capacity 
5.7.1.2 Other parameters tested 
5.8 Bibliography 
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6 Relays J'. W.Hodgkiss 339 
6.1 Introduction 339 
6.2 Principal types of relays 
6.2.1 Attracted-armature relays 
6.2.2 Moving-coil relays 
6.2.3 Induction relays 
6.2.4 Thermal relays 
6.2.5 Motor-operated relays 
6.2.6 Gas- and oil-operated relays (Buchholz relays) 
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Contents 
6.3 
6.4 
6.5 
Auxiliary d.c. relays 
6.3.1 Operating-voltage limits 
6.3.2 Discharge of wiring capacitance 
6.3.3 Tripping relays 
6.3.4 Time-lag relays 
6.3.5 Repeat contactors 
6.3.6 Trip-circuitsupervision 
6.3.7 Alarm relays 
General design considerations 
6.4.1 Coil ratings 
6.4.2 Auxiliary supplies 
6.4.3 Relay setting adjustment 
6.4.4 Contacts 
6.4.5 Flag indicators 
6.4.6 Resetting 
Static relays 
6.5. I Basic circuits employed 
6.5.1 .I Timers 
6.5 .I .2 Level detectors 
6.5.1.3 Polarity detectors 
6.5.1.4 Phase comparators 
6.5.1.5 Integrators 
6.5.2 Components 
6.5.2.1 Resistors 
6.5.2.2 Capacitors 
6.5.2.3 Diodes 
6.5.2.4 Connectors 
6.5.3 Transient overvoltages and interference 
6.5.3.1 Sources of transients 
6.5.3.2 Standard tests 
6.5.3.3 Protection against transients 
6.5.4 Power supplies for static relays 
6.5.5 Output and indicating circuits 
6.6 Relay cases 
6.7 Maintenance 
6.8 Application and characteristics 
6.8.1 
6.8.2 
6.8.3 
6.8.4 
6.8.5 
6.8.6 
6.8.7 
6.8.8 
6.8.9 
6.8.10 
6.8.1 1 
Instantaneous current- and voltage-operated relays 
Double-quantity measurement 
Presentation of characteristics 
Complex input comparators 
Distance relays 
Rectifier bridge comparators 
Phase-comparison bridge 
Range curves 
Differential relays 
Polar curves 
Negative-sequence protection 
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Cont~n~ 
6.9 
6.10 
6.11 
7 
7.1 
7.2 
7.3 
7.4 
7.5 
Testing of relays and protection schemes 
6.9.1 Test at manufacturing works 
6.9.2 Testing at sire 
Future trends in relay des/gn 
Bibliography 
Protection signalling P. C. Colbrook 
Introduction 
Commun/cation media 
7.2. I Power-line carrier 
7.2.1 .I General 
7.2.1.2 Coupling equipment 
7.2.1.3 Design principles of coupling equipment 
7.2. 1.4 Coupling bands 
7.2.1.5 Protection and earthing of coupling equipment 
7.2.1.6 Attenuation 
7.2.1.7 Application to feed circuits 
7.2.1.8 Application to circuits containing cable sections 
7.2.2 Private pilots 
7.2.2.1 Underground pilot cables 
7,2.2.2 Overhead pilots 
7,2.3 Rented pilot circuits 
7.2.3.1 General 
7.2.3.2 Types of rented pilot circuit 
7.2.3.3 pilot-circuit characteristics 
7.2.4 Radio links 
7.2.4.1 General 
7.2.4.2 Microwave radio links 
7.2.5 Optical-fibre links 
Fundamental signilllng problem 
7.3.1 Effects of noise 
7.3.2 Characteristics of electrical noise 
7.3.3 Equipment design principles 
Performance requirements of signalling facilities and equipment 
7.4.1 Operating times 
7.4.1.I General 
7.4.1.2 Equipment operating time classification 
7.4.2 Reliability of operation 
7.4.3 Security against maloperation 
7.4.4 Pulse distortion 
7.4.5 Power supplies 
7.4.6 Other performance requirements 
Methods of signalling 
7.5.1 D.C. intertripping 
7.5.2 Low-frequency a.c. intertripping over private pilots 
7.5.3 Voice-frequency signalling equipment 
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Contents 
7.6 
Index 
7.5.4 
7.5.3.1 General 505 
7.5.3.2 V.F. protection signalling equipment 506 
7.5.3.3 V.F. intertripping equipment 507 
Power-line-carrier signalling equipment 513 
7.5.4.1 Keyed carrier equipment 513 
7.5.4.2 Carrier frequency-shift equipment 513 
7.5.4.3 Single-sideband power-line-carrier communication 
equipment 516 
Bibliography 516 
518 
	Front Matter
	Protection Symbols Used in Circuit Diagrams
	Volume 1: Principles and Components
	Table of Contents
	1. Role of Protection
	1.1 Introduction
	1.1.1 General Considerations
	1.1.2 Role of Protection in a Power System
	1.2 System and Substation Layout
	1.2.1 System Layout
	1.2.2 Substation Layout (Electrical)
	1.2.3 Current Transformer Location
	1.3 System Earthing
	1.3.1 Neutral-Earthing Methods
	1.3.2 Special Cases of Resistance Earthing
	1.4 Faults
	1.4.1 Faults and Other Abnormalities
	1.4.2 Nature and Causes of Faults
	1.4.3 Fault Statistics
	1.5 Basic Terms Used in Protection
	1.6 Necessity for Back-Up Protection
	1.7 Economic Considerations
	1.7.1 General
	1.7.2 Distribution Systems
	1.7.3 Transmission Systems
	1.8 Bibliography
	2. Protection Principles and Components
	2.1 Fundamental Principles
	2.1.1 Methods of Discrimination
	2.1.2 Derivation of Relaying Quantities
	2.1.3 Combined Overcurrent and Earth Fault Relays
	2.1.4 Derivation of a Representative Single-Phase Quantity from a Three-Phase System
	2.2 Components of Protection
	2.2.1 Relays
	2.2.2 Current Transformers
	2.2.3 Voltage Transforming Devices
	2.2.4 Capacitor Dividers
	2.2.5 H.F. Capacitor Couplers
	2.2.6 Line Traps
	2.2.7 Circuit-Breakers
	2.2.8 Tripping and Other Auxiliary Supplies
	2.2.9 Fuses, Small Wiring, Terminals and Test Links
	2.2.10 Pilot Circuits
	2.3 Consideration of the Protection Problem
	2.4 Bibliography
	3. Fault Calculations
	3.1 Introduction
	3.1.1 Purpose of Fault Calculation
	3.1.2 Types of Fault
	3.1.3 Factors Affecting Fault Severity
	3.1.4 Methods of Fault Calculation
	3.2 Basic Principles of Network Analysis
	3.2.1 Fundamental Network Laws
	3.2.2 Mesh-Current Analysis
	3.2.3 Nodal-Voltage Analysis
	3.2.4 Application of Mesh-Current and Nodal Voltage Analysis
	3.2.5 Network Theorems and Reduction Formulas
	3.3 Calculations of Balanced Fault Conditions
	3.3.1 Single-Phase Representation
	3.3.2 Use of a Common Voltage Base
	3.3.3 Representation of Nominal-Ratio Transformer Circuits
	3.3.4 Representation of Off-Nominal-Ratio Transformer Circuits
	3.3.5 Transformer Phase-Shifts
	3.3.6 Representation of Synchronous Machines
	3.3.7 Use of Per-Unit and Per-Cent Values
	3.3.8 Fault-Calculation Procedure
	3.3.9 Example 1
	3.3.10 Example 2
	3.4 Calculation of Unbalanced Fault Conditions
	3.4.1 Symmetrical Components
	3.4.2 Phase-Sequence Networks and Impedances
	3.4.3 Phase-Sequence Equivalent Circuits
	3.4.4 Analysis of Short-Circuit Conditions
	3.4.5 Effect of Fault Impedance
	3.4.6 Analysis of Open-Circuit Conditions
	3.4.7 Transformer Phase-Shifts
	3.4.8 Fault-Calculation Procedure
	3.4.9 Example 3
	3.4.10 Example 4
	3.4.11 Example 5
	3.4.12 Example 6
	3.5 Calculation of Simultaneous Fault Conditions
	3.5.1 Sequence Networks
	3.5.2 Cross-Country Earth-Fault
	3.5.3 Sequence Network Interconnections
	3.5.4 Example 7
	3.5.5 Example 8
	3.6 Practical Network Analysis
	3.6.1 Network Analysers
	3.6.1.1 A.C. Analyser
	3.6.1.2 D.C. Analyser
	3.6.2 Digital-Computer Analysis
	3.6.3 Transient Analysis
	3.7 Winding Faults
	3.7.1 General Considerations
	3.7.2 Generator-Winding Faults
	3.7.3 Transformer-Winding Faults
	3.8 Appendixes
	3.8.1 Representation of Off-Nominal-Ratio Transformers
	3.8.2 Effects of Overhead-Fine Asymmetry
	3.9 Bibliography
	4. Protective Transformers
	4.1 General
	4.1.1 Introduction
	4.1.2 Basic Transformer Principles
	4.2 Steady-State Theory of Current Transformers
	4.2.1 Equivalent Circuit, Vector Diagram, Errors
	4.2.2 Influence of the Core, Magnetic Materials, and Magnetisation Curves
	4.2.3 Single-Turn Primary Current Transformers
	4.2.4 Flux Leakage
	4.2.5 Balancing Windings and Eddy-Current Shielding
	4.2.6 Open-Circuit Secondary Voltage
	4.2.7 Secondary Currents, Burdens and Connecting Lead Resistance
	4.2.8 Test Windings
	4.3 Current Transformers for Protection
	4.3.1 Saturation of the Core and Ratio on Overcurrents. BS 3938
	4.3.2 Trip-Coil Operation
	4.3.3 Overcurrent-Relay Operation
	4.3.4 Earth-Fault Relays with Inverse-Time Characteristics
	4.3.5 Relay Settings and Primary Operating Currents
	4.3.6 Current Transformers for Balanced Differential Protective Schemes
	4.3.7 Simple Transient-State Theory
	4.4 Construction of Current Transformers
	4.4.1 Basic Types
	4.4.2 Forms of Cores
	4.4.3 Windings and Insulation
	4.4.4 High-Voltage Current Transformers
	4.5 Testing of Current Transformers
	4.5.1 Error Measurements
	4.5.2 Turns Ratio Tests
	4.5.3 Exciting Current
	4.5.4 Current Transformers for Balanced Differential ProtectiveSchemes
	4.5.5 Polarity
	4.5.6 Insulation Tests
	4.6 Voltage-Transformer Theory
	4.6.1 Electromagnetic-Type Voltage Transformers
	4.6.2 Capacitor-Type Voltage Transformers
	4.6.3 Burdens and Lead Resistances
	4.7 Voltage Transformers for Protection
	4.7.1 Electromagnetic Type Categories, Residual Voltages
	4.7.2 Capacitor Type
	4.8 Construction of Voltage Transformers
	4.8.1 Electromagnetic Type
	4.8.2 Cascade Type
	4.8.3 Capacitor Type
	4.8.4 Capacitor Divider Voltage Sensor
	4.8.5 Voltage Transformers for SF_6 Metalclad Switchgear
	4.9 Fusing And Protection of Voltage Transformers
	4.10 Testing of Voltage Transformers
	4.10.1 Error Measurements
	4.10.2 Core Losses
	4.10.3 Insulation Tests
	4.10.4 Polarity
	4.11 Bibliography
	5. Fuses
	5.1 Introduction
	5.1.1 Definition of a Fuse
	5.1.2 Definition of a Fuselink
	5.1.3 Categories of Fuse
	5.2 Fuse Design
	5.2.1 Powder-Filled Cartridge Fuse
	5.2.1.1 High-Voltage Powder-Filled Fuses
	5.2.2 Miniature Fuselink
	5.2.3 Semi-Enclosed Fuse
	5.2.4 Expulsion Fuse
	5.2.5 Other Fuse Developments
	5.3 Mechanism of Fuse Operation
	5.3.1 Operation on Small Overcurrents
	5.3.2 Operation on Large Overcurrents
	5.3.3 Operation on Intermediate Overcurrents
	5.3.4 Operation on Pulsed Loading
	5.3.5 Fulgurite (Roping)
	5.3.6 Typical Oscillograms
	5.4 Peak Arc Voltage
	5.5 Time/Current Characteristic And Factors Affecting It
	5.5.1 Definitions Related to the Operation of Fuses at the Small Overcurrent Region of the Time/Current Characteristic and the Assignment of Current Rating
	5.6 Discrimination
	5.6.1 Discrimination Between Fuselinks
	5.6.2 Discrimination Between H.V. and L.V. Fuses and Circuit- Breaking Devices
	5.7 Testing of Fuses
	5.7.1 Fuse Testing on A.C.
	5.7.1.1 Breaking Capacity
	5.7.1.2 Other Parameters Tested
	5.8 Bibliography
	6. Relays
	6.1 Introduction
	6.2 Principal Types of Relays
	6.2.1 Attracted-Armature Relays
	6.2.2 Moving-Coil Relays
	6.2.3 Induction Relays
	6.2.4 Thermal Relays
	6.2.5 Motor-Operated Relays
	6.2.6 Gas- and Oil-Operated Relays (Buchholz Relays)
	6.3 Auxiliary D.C. Relays
	6.3.1 Operating-Voltage Limits
	6.3.2 Discharge of Wiring Capacitance
	6.3.3 Tripping Relays
	6.3.4 Time-Lag Relays
	6.3.5 Repeat Contactors
	6.3.6 Trip-Circuit Supervision
	6.3.7 Alarm Relays
	6.4 General Design Considerations
	6.4.1 Coil Ratings
	6.4.2 Auxiliary Supplies
	6.4.3 Relay Setting Adjustment
	6.4.4 Contacts
	6.4.5 Flag Indicators
	6.4.6 Resetting
	6.5 Static Relays
	6.5.1 Basic Circuits Employed
	6.5.1.1 Timers
	6.5.1.2 Level Detectors
	6.5.1.3 Polarity Detectors
	6.5.1.4 Phase Comparators
	6.5.1.5 Integrators
	6.5.2 Components
	6.5.2.1 Resistors
	6.5.2.2 Capacitors
	6.5.2.3 Diodes
	6.5.2.4 Connectors
	6.5.3 Transient Overvoltages and Interference
	6.5.3.1 Sources of Transients
	6.5.3.2 Standard Tests
	6.5.3.3 Protection Against Transients
	6.5.4 Power Supplies for Static Relays
	6.5.5 Output and Indicating Circuits
	6.6 Relay Cases
	6.7 Maintenance
	6.8 Application and Characteristics
	6.8.1 Instantaneous Current- and Voltage-Operated Relays
	6.8.2 Double-Quantity Measurement
	6.8.3 Presentation of Characteristics
	6.8.4 Complex Input Comparators
	6.8.5 Distance Relays
	6.8.6 Rectifier Bridge Comparators
	6.8.7 Phase-Comparison Bridge
	6.8.8 Range Curves
	6.8.9 Differential Relays
	6.8.10 Polar Curves
	6.8.11 Negative-Sequence Protection
	6.9 Testing of Relays and Protection Schemes
	6.9.1 Test at Manufacturing Works
	6.9.2 Testing at Site
	6.10 Future Trends in Relay Design
	6.11 Bibliography
	7. Protection Signalling
	7.1 Introduction
	7.2 Communication Media
	7.2.1 Power-Line Carrier
	7.2.1.1 General
	7.2.1.2 Coupling Equipment
	7.2.1.3 Design Principles of Coupling Equipment
	7.2.1.4 Coupling Bands
	7.2.1.5 Protection and Earthing of Coupling Equipment
	7.2.1.6 Attenuation
	7.2.1.7 Application to Teed Circuits
	7.2.1.8 Application to Circuits Containing Cable Sections
	7.2.2 Private Pilots
	7.2.2.1 Underground Pilot Cables
	7.2.2.2 Overhead Pilots
	7.2.3 Rented Pilot Circuits
	7.2.3.1 General
	7.2.3.2 Types of Rented Pilot Circuit
	7.2.3.3 Pilot-Circuit Characteristics
	7.2.4 Radio Links
	7.2.4.1 General
	7.2.4.2 Microwave Radio Links
	7.2.5 Optical-Fibre Links
	7.3 Fundamental Signalling Problem
	7.3.1 Effects of Noise
	7.3.2 Characteristics of Electrical Noise
	7.3.3 Equipment Design Principles
	7.4 Performance Requirements of Signalling Facilities and Equipment
	7.4.1 Operating Times
	7.4.1.1 General
	7.4.1.2 Equipment Operating Time Classification
	7.4.2 Reliability of Operation
	7.4.3 Security Against Maloperation
	7.4.4 Pulse Distortion
	7.4.5 Power Supplies
	7.4.6 Other Performance Requirements
	7.5 Methods of Signalling
	7.5.1 D.C. Intertripping
	7.5.2 Low-Frequency A.C. Intertripping Over Private Pilots
	7.5.3 Voice-Frequency Signalling Equipment
	7.5.3.1 General
	7.5.3.2 V.F. Protection Signalling Equipment
	7.5.3.3 V.F. Intertripping Equipment
	7.5.4 Power-Line-Carrier Signalling Equipment
	7.5.4.1 Keyed Carrier Equipment
	7.5.4.2 Carrier Frequency-Shift Equipment
	7.5.4.3 Single-Sideband Power-Line-Carrier Communication Equipment
	7.6 Bibliography
	Index
	A
	B
	C
	D
	E
	F
	G
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	Z
	Volume 2: Systems and Methods
	Table of Contents
	8. Overcurrent Protection
	8.1 Introduction
	8.2 Types of Overcurrent System
	8.2.1 Overcurrent and Earth-fault Protection Systems
	8.2.2 Grading of Current Settings
	8.2.3 Grading of Time Settings: The Definite-time System
	8.2.4 Grading by Both Time and Current: Inverse-time Overcurrent Systems
	8.2.4.1 Fuses
	8.2.4.2 Delayed Action Trip Coils
	8.2.4.3 Fuse-shunted Trip Coils
	8.2.4.4 Inverse-time Overcurrent Relays
	8.3 Selection of Settings
	8.3.1 System Analysis
	8.3.2 Grading of Relay Settings
	8.3.2.1 Grading for Definite-time Relays
	8.3.2.2 Grading for Inverse-time Relays
	8.3.2.3 Grading with 'Very Inverse' Relays
	8.3.2.4 Graphical Method of Grading
	8.3.3 Current Transformer Requirements
	8.3.3.1 Burdens
	8.3.3.2 Variation of Burden Impedance
	8.3.3.3 Additional Burden
	8.3.3.4 Significance of Leads
	8.3.3.5 Burden of Earth-fault Schemes
	8.3.3.6 Effective Setting
	8.3.3.7 Time-grading of Earth-fault Relays
	8.3.3.8 Phase-fault Stability
	8.3.4 Sensitive Earth-fault Protection
	8.3.5 High-set Instantaneous Overcurrent Relays
	8.3.6 Relay Co-ordination with Fuses
	8.4 Directional Control
	8.4.1 Directional Relays
	8.4.2 Connections for Directional Phase-fault Relays
	8.4.2.1 30° Relay Connection: m.t.a. = 0°
	8.4.2.2 60° Relay Connection: m.t.a. = 0°
	8.4.2.3 90° Relay Connection
	8.4.3 Directional Earth-fault Relays
	8.4.3.1 Polarisation by Residual Voltage
	8.4.3.2 Polarisation by Neutral Current
	8.4.3.3 Dual Polarisation
	8.4.4 Grading of Ring Mains
	8.4.5 Multiple-fed Ring Mains
	8.4.6 Parallel Feeders
	8.5 Bibliography
	9. Feeder Protection: Distance Systems
	9.1 Introduction
	9.2 Historical
	9.3 Operating Principles
	9.3.1 Impedance Measurement
	9.3.2 Derivation of Basic Measuring Quantities
	9.4 Impedance-measuring Elements (Comparators) and Their Characteristics
	9.4.1 Presentation of Characteristics
	9.4.2 Derivation of Relay Characteristics
	9.4.3 Equivalence of Amplitude and Phase Comparators
	9.4.4 Basic Range of Impedance Characteristics
	9.4.5 Measuring Characteristics of Relay Schemes
	9.4.6 Mho Characteristics
	9.4.7 Practical Polarised Mho Characteristic
	9.5 Development of Comparators
	9.5.1 Induction Cup
	9.5.2 Rectifier Bridge Moving Coil
	9.5.3 Electronic Relays: Introduction
	9.5.4 Comparator Development
	9.5.5 Practical Realisation of Static Phase Comparators
	9.6 More Complex Relaying Characteristics
	9.6.1 Basis for Shaped Polar Characteristics
	9.6.2 Change of Angular Criterion
	9.6.3 Multicomparator Schemes
	9.6.4 Multi-input Comparators
	9.6.5 Alternative Characteristics
	9.7 Presentation of Performance
	9.7.1 Requirements
	9.7.2 Display of Measuring Accuracy
	9.7.3 Display of Operating Time
	9.7.4 Application of Contour Timing Curves
	9.7.5 Alternative Methods of Presentation9.7.6 Steady-state Performance Presentation
	9.7.7 Dynamic Polar Characteristics
	9.8 Switched and Polyphase Distance Protection
	9.8.1 Introduction
	9.8.2 Switched Distance Protection
	9.8.3 Polyphase Distance Protection
	9.9 Distance Protection Schemes Based on Information Links
	9.9.1 General
	9.9.2 Tripping Schemes
	9.9.2.1 Direct Intertrip
	9.9.2.2 Permissive Intertrip-underreaching Schemes
	9.9.2.3 Permissive Intertrip-overeaching Systems
	9.9.3 Blocking Schemes
	9.9.3.1 Distance Protection Blocking Scheme
	9.9.3.2 Directional Comparison
	9.10 Practical Considerations in the Application of Distance Protection
	9.10.1 Fault Resistance
	9.10.2 Measuring Errors
	9.10.3 Healthy Phase Relays
	9.10.4 Load Encroachment
	9.10.5 Power Swing Encroachment
	9.10.6 Line Check
	9.10.7 Voltage Transformer Supervision
	9.11 Trends in Distance Protection Development
	9.12 Bibliography
	10. Feeder Protection - Pilot Wire and Carrier-Current Systems
	10.1 General Background and Introduction
	10.2 Some Basic Concepts of Unit Protection for Feeders
	10.3 Basic Types of Protection Information Channels
	10.3.1 Pilot Wires
	10.3.2 Main Conductors
	10.3.3 Radio Links
	10.4 Types of Information Used
	10.4.1 Complete Information on Magnitude and Phase of Primary Current
	10.4.2 Phase-angle Information Only
	10.4.3 Simple Two-state (off/on) Information
	10.5 Starting Relays
	10.6 Conversion of Polyphase Primary Quantities to a Single-phase Secondary Quantity
	10.6.1 General Philosophy
	10.6.2 Interconnections of Current Transformers
	10.6.3 Summation Transformers
	10.6.4 Phase-sequence Current Networks
	10.7 Elementary Theory of Longitudinal Differential Protection
	10.7.1 Longitudinal Differential Protection with Biased Relays
	10.7.2 Phase-comparison Principles
	10.7.3 Nonlinear Differential Systems
	10.7.4 Directional Comparison Systems
	10.7.5 Current Sources and Voltage Sources
	10.7.6 Nonlinearity and Limiting
	10.8 Pilot-wire Protection
	10.8.1 Basic Principles
	10.8.2 Practical Relay Circuits
	10.8.3 Summation Circuits
	10.8.4 Basic Discrimination Factor
	10.8.5 Typical Pilot Circuits
	10.8.6 Typical Systems for Privately Owned Pilots
	10.8.7 Use of Rented Pilots
	10.8.8 Typical Systems for use with Rented Pilots
	10.8.9 V.F. Phase-comparison Protection (Reyrolle Protection)
	10.9 Some Aspects of Application of Pilot-wire Feeder Protection
	10.9.1 General
	10.9.2 Current Transformer Requirements
	10.9.3 Operating Times
	10.9.4 Fault Settings
	10.9.5 Protection Characteristics
	10.10 Power-line Carrier Phase-comparison Protection
	10.10.1 Introduction
	10.10.2 Types of Information Transmitted
	10.10.3 Basic Principles of Phase-comparison Protection
	10.10.4 Summation Networks
	10.10.5 Modulation of H.F. Signal
	10.10.6 Junction Between Transmitted and Received Signals
	10.10.7 Receiver
	10.10.8 Tripping Circuit
	10.10.9 Starting Circuits
	10.10.10 Telephase T3
	10.10.11 Contraphase P10
	10.10.12 Marginal Guard
	10.10.13 Checking and Testing
	10.11 Problems of Application of Phase-comparison Feeder Protection
	10.11.1 General
	10.11.2 Attenuation Over the Line Length
	10.11.3 Tripping and Stabilising Angles
	10.11.4 Fault Settings Related to Capacitance Current
	10.11.5 C.T. Requirements
	10.12 Directional Comparison Protection
	10.12.1 General
	10.12.2 Basic Principles
	10.12.3 Basic Units
	10.12.4 Directional Relays
	10.12.5 Fault Detecting
	10.12.6 Change of Fault Direction
	10.13 Power Supplies
	10.13.1 General
	10.13.2 Station Battery Supply
	10.13.3 Separate Batteries
	10.14 Bibliography
	11. Overvoltage Protection
	11.1 Overvoltage Phenomena in Power Systems
	11.1.1 External Overvoltages (Lightning)
	11.1.2 Internal Overvoltages
	11.2 Travelling Waves
	11.2.1 Wave Propagation Along a Transmission Line without Losses
	11.2.2 Reflections at the End of the Line
	11.2.3 Discontinuities in Surge Impedance and Junctions with Infinitely Long Lines
	11.2.4 Effect of Waveshape and of Finite Length of Lines
	11.3 Insulation Co-ordination
	11.3.1 Fundamental Principles of Surge Protection and Insulation Co-ordination
	11.3.2 Basic Requirements
	11.3.3 Insulation and Protective Levels
	11.3.4 Relation Between Overvoltage Tests and Service Conditions
	11.3.5 Practical Choice of Insulation Levels
	11.4 Protection Against External Overvoltages
	11.4.1 Shielding of Overhead Lines and Substations
	11.4.2 Surge Protection by Effective System Layout
	11.4.3 Voltage Limiting Devices
	11.5 Protection Against Internal Overvoltages
	11.5.1 Protection Against Switching Transients
	11.5.2 Protection Aagainst Sustained Internal Overvoltages
	11.5.3 Protection Against Internal Temporary Overvoltages
	11.6 Practical Aspects and Some Special Problems of Insulation Co-ordination and Surge Protection
	11.6.1 Effect of System Neutral Earthing on Insulation Requirements
	11.6.2 Choice of Surge Arresters and Derivation of Basic Impulse Insulation Levels
	11.6.3 Clearances to Earth Between Phases and Across Isolating Gaps
	11.6.4 Standard Insulation Levels, Clearances with Recommended Co-ordinating Gap Settings, or Surge Arrester Ratings, or Both
	11.6.5 Effect of Rain, Humidity and Atmospheric Pollution
	11.7 Probabilistic or Statistical Approach in Insulation Co-ordination
	11.7.1 Statistical Aspects of Overvoltages and Insulation Strength
	11.7.2 Application of Statistical Distribution to Insulation Co-ordination
	11.8 Economic Aspects
	11.9 Bibliography
	Index
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	Volume 3: Application
	Table of Contents
	12. Protection of Generators, Transformers, Generator-transformer Units and Transformer Feeders
	12.1 Introduction
	12.2 Performance Requirements
	12.2.1 Generator Faults
	12.2.2 Transformer Faults
	12.3 Generator Protection Systems
	12.3.1 Unbiased Differential Protection
	12.3.2 Biased Differential Protection
	12.3.3 Back-up Overcurrent and Earth-fault Protection
	12.3.4 Negative Phase-sequence Protection
	12.3.5 Interturn Fault Protection
	12.3.6 Loss of Excitation (Field Failure) Protection
	12.3.7 Protection Against Pole-slipping
	12.3.8 Rotor Earth-fault Protection
	12.3.9 Sensitive Power Protection
	12.3.10 Low Forward Power Interlock
	12.3.11 Overspeed Protection
	12.3.12 Underexcitation Limiting
	12.3.13 Mechanical and Hydraulic Trips
	12.4 Gas-turbine Driven Generators
	12.4.1 Direct Connected, Gas-turbine Sets
	12.4.2 Transformer Connected, Gas-turbine Sets
	12.5 Transformer Protection
	12.5.1 Unbiased Differential Protection
	12.5.2 Biased Differential Protection
	12.5.3 Restricted Earth-fault Protection
	12.5.4 Overcurrent Protection
	12.5.5 Directional Overcurrent Protection
	12.5.6 Interlocked Overcurrent Protection
	12.5.7 Standby Earth-fault Protection
	12.5.8 Tank Earth-fault Protection
	12.5.9 Winding Temperature Protection
	12.5.10 Gas Generation and Oil-surge Protection
	12.6 Protection Schemes for Typical Transformers
	12.6.1 Distribution Transformers
	12.6.2 Two-winding Transmission Transformers
	12.6.3 Station Transformers
	12.6.4 Autotransformers for Transmission
	12.7 Protection System for Generator Transformer Units
	12.7.1 Biased Differential Protection
	12.7.2 Stator Earth-fault Protection
	12.7.3 Tripping Arrangements
	12.7.4 Generator Transformer Overfluxing Protection
	12.8 Transformer Feeder Protection
	12.8.1 Overall Protection for Feeder and Transformer
	12.8.2 Separate Protection for Feeder and Transformer
	12.8.3 Intertripping
	12.8.4 Neutral Displacement Protection
	12.8.5 Directional Overcurrent Protection
	12.8.6 Typical Protection Arrangements for Transformer Feeders
	12.9 Bibliography
	13. Busbar Protection
	13.1 History of the Development of Busbar Protection
	13.2 General Considerations
	13.2.1 The Basic Philosophy of Busbar Protection
	13.2.2 Earth-fault Protection Versus Phase and Earth-fault Protection
	13.3 The Clearance of Busbar Faults by Non-unit Circuit Protection
	13.3.1 Back-up Overcurrent and Earth-fault Relays
	13.3.2 Distance Protection
	13.4 Unit Systems of Busbar Protection for MetalcladDistribution Switchgear
	13.4.1 General Considerations
	13.4.2 Frame Earth Systems
	13.5 Unit Systems of Busbar Protection for Transmission Substations
	13.5.1 General Considerations
	13.5.2 Current Balance Using Circulating Current Principle
	13.5.3 Connections for Circulating Current Busbar Protection
	13.5.4 The Influence of C.T. Performance on Through-fault Stability
	13.5.5 Basic Principles of High-impedance Circulating Current Busbar Protection: Stability
	13.5.6 Basic Principles of High-impedance Circulating Current Busbar Protection: Operation
	13.5.7 Extension of the Basic Principles to Busbar Protection
	13.5.8 Types of High-impedance Relays
	13.5.9 Practical High-impedance Installations
	13.6 Practical Considerations
	13.6.1 Factors Affecting the Position of C.T.S in Busbars
	13.6.2 Effect of C.T. Location in Outgoing Circuits
	13.6.3 Multiple Check Zones
	13.6.4 Busbar Selector Auxiliary Switches
	13.6.5 C.T. Test Links
	13.6.6 Precautions Against Maloperation of Busbar Protection
	13.6.7 Tripping and Alarm Circuit Arrangements
	13.6.8 Back-tripping
	13.6.9 Test Facilities
	13.6.10 Fault Settings
	13.6.11 Stability Limits
	13.7 Circuit Breaker Fail Protection
	13.7.1 Principle of Operation
	13.7.2 Precautions Against Maloperation
	13.7.3 Current Check Relay Settings
	13.7.4 Circuit Breaker Fail Timer Settings
	13.8 Terminology
	13.9 Bibliography
	14. Protection of Motors, Reactors, Boosters and Capacitors
	14.1 Introduction
	14.2 Motors
	14.2.1 Characteristics of D.C. and A.C. Motors
	14.2.2 Application of D.C. and A.C. Motors
	14.2.3 Motor Control
	14.2.4 Types of Fault
	14.2.5 A.C. and D.C. Motor Protection
	14.3 Reactors
	14.3.1 The Place of Reactors in a Power System
	14.3.2 Types of Reactor
	14.3.3 Reactor Rating
	14.3.4 Reactor Application
	14.3.5 Reactor Protection
	14.4 Boosters
	14.4.1 The Place of Boosters in a Power System
	14.4.2 Transformer Tap-changing
	14.4.3 Booster Transformers
	14.4.4 The Moving-coil Regulator
	14.4.5 The Induction Regulator
	14.4.6 Protection of Boosters
	14.5 Capacitors
	14.5.1 Capacitors in an Interconnected Power System
	14.5.2 Series-connected Capacitors
	14.5.3 Shunt-connected Capacitors
	14.5.4 Series or Shunt Connection
	14.5.5 The Capacitor Unit
	14.5.6 Protection of Capacitors
	14.5.6.1 Series Capacitor Internal Protection
	14.5.6.2 Series Capacitor External Protection
	14.5.6.3 Shunt Capacitor Internal Protection
	14.5.6.4 Shunt Capacitor External Protection
	14.5.6.5 Protection of Synchronous Shunt Compensators
	14.6 Bibliography
	15. The Application of Protection to Rural Distribution Systems
	15.1 Introduction
	15.2 Fuses
	15.2.1 Types Employed
	15.2.2 Application
	15.3 Automatic Circuit Reclosing
	15.3.1 Principle
	15.3.2 Repeater Fuses
	15.3.3 Pole-mounted Automatic Circuit Reclosers
	15.3.4 Substation Circuit Breakers
	15.4 Sensitive Earth-fault Protection
	15.5 Arc-suppression Coils
	15.6 Performance/Cost Comparison of Protective Equipment for Rural Systems
	15.7 Primary Networks in Rural Areas
	15.8 Bibliography
	16. The Application of Protection to Urban and Metropolitan Systems
	16.1 Introduction
	16.2 Characteristics of Urban and Metropolitan Areas
	16.3 Distribution System Protection - Radial L.V. Systems
	16.3.1 Services
	16.3.2 L.V. Cables
	16.3.3 Substation Transformers
	16.3.4 H.V. Cables
	16.3.5 Primary Substations
	16.4 Distribution System Protection - Interconnected L.V. Systems
	16.4.1 The L.V. Network
	16.4.2 Substations
	16.4.3 The H.V. Network
	16.4.4 Protection on a Distributed Block L.V. Interconnected System
	16.4.5 Supply to Large Point Loads
	16.4.6 Supply to H.V. Consumers
	16.5 Private Generation
	16.6 Future Trends
	16.7 Bibliography
	17. The Application of Protection to Transmission Systems
	17.1 General Principles of Application of Protection to Transmission Systems
	17.1.1 Introduction
	17.1.2 System Design Considerations
	17.1.3 Factors Which Influence the Choice of Protection
	17.1.3.1 Plant to be Protected
	17.1.3.2 Probability of Various Types of Fault
	17.1.3.3 Load and Fault Currents
	17.1.3.4 Voltage and Current Ratings of Protected Plant
	17.1.3.5 Necessity or Otherwise for High-speed Operation
	17.1.3.6 Importance of Security of Supply
	17.1.3.7 Compatibility with Existing Protection
	17.1.3.8 Availability of Signalling Channels
	17.1.3.9 Cost
	17.2 Main and Back-up Protection and Location of Current Transformers
	17.2.1 Main and Back-up Protection
	17.2.1.1 Main Protection
	17.2.1.2 Back-up Protection
	17.2.2 Effect of Location of Current Transformers in Determining Protection to be Provided
	17.2.3 Two-stage Overcurrent Protection
	17.3 Intertripping and Protection Signalling
	17.3.1 General
	17.3.2 D.C. Signalling
	17.3.3 Post Office Signalling
	17.3.4 Carrier Signalling
	17.3.5 Fault Throwing
	17.4 Automatic Switching
	17.4.1 Design and Application of Automatic Switching Equipment
	17.4.2 High-speed Automatic Reclosing
	17.4.3 Delayed Automatic Reclosing
	17.4.4 Equipment Design and Programming
	17.4.5 Commissioning
	17.5 Economic Considerations
	17.6 Typical Protection Applications in a Major Transmission System
	17.6.1 Feeder Protection
	17.6.1.1 Protection for a Long Overhead Feeder
	17.6.1.2 Protection for a Short Overhead Feeder
	17.6.1.3 Protection for an Underground Feeder
	17.6.2 Protection for a Transformer
	17.6.3 Protection for Banked Transformers
	17.6.4 Protection for a Teed Feeder
	17.6.5 Protection for a Transformer-feeder
	17.6.6 Protection for a Double-busbar Station
	17.6.7 Protection for Mesh Stations
	17.6.8 Protection for Complex Primary Circuit Configurations
	17.7 Typical Protection Applications in a Minor Transmission System or Major Distribution System
	17.7.1 Protection for a Feeder
	17.7.2 Protection for a Transformer
	17.7.3 Protection for Banked Transformers and Dual Secondary Transformers
	17.7.4 Protection for a Teed Feeder
	17.7.5 Protection for a Transformer Feeder
	17.7.6 Protection for a Double Busbar and Mesh Station
	17.7.7 Protection for Complex Primary Circuit Configurations
	17.8 Bibliography
	18. Testing, Commissioning and Management of Protection
	18.1 Introduction
	18.2 Contractual Obligations
	18.3 The Mental Approach to Commissioning Tests
	18.4 Commissioning Tests
	18.4.1 Reasons for Commissioning Tests
	18.4.2 Planning of Commissioning Tests
	18.4.3 Inspection Prior to Testing
	18.4.4 The Tests
	18.4.5 Phasing Tests
	18.4.6 Closing Up
	18.4.7 On-load Tests
	18.4.8 Modification to Existing Substations
	18.5 Routine Maintenance Tests
	18.5.1 Causes and Effects of Deterioration
	18.5.2 Frequency of Routine Maintenance
	18.5.3 Inspections and Tests
	18.5.4 Maintenance of Busbar Protection, Back-tripping and Circuit-breaker Fail Protection at Double-busbar Type Substations
	18.5.5 Maintenance and Testing of Intertripping and Protection Signalling Equipment
	18.6 Fault Investigation
	18.6.1 Primary Faults
	18.6.2 Faults on the Protective Equipment
	18.6.3 Faults on Solid-state Equipment
	18.7 The Avoidance of Errors When Testing
	18.7.1 General
	18.8 The Test Equipment
	18.9 Records
	18.9.1 Relay Settings
	18.9.2 Test Results
	Index
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	Volume 4: Digital Protection and Signalling
	Table of Contents
	1. Digital Technology
	1.0 Introduction
	1.1 Logic Devices
	1.2 Microprocessors
	1.2.1 Historical Development
	1.2.2 Basic Operation
	1.2.3 Memory Devices
	1.2.4 Binary Number Representation
	1.2.5 Programming
	1.3 Analogue to Digital Conversion
	1.3.1 Introduction
	1.3.2 Digital to Analogue Converters
	1.3.3 Analogue to Digital Converters: Ramp Converters
	1.3.4 Analogue to Digital Converters: Successive Approximation Converters
	1.3.5 Sample and Hold Amplifiers
	1.3.6 Multiplexers
	1.3.7 Analogue to Digital Conversion in Protection Relays
	1.4 Specialised Microprocessors
	1.5 Reference
	2. Digital Signal Processing
	2.0 Introduction
	2.1 Continuous Versus Discrete Waveforms
	2.2 Sampling
	2.3 Digital Filtering
	2.3.1 Time Domains and Frequency Domains
	2.3.2 FilterDescriptions
	2.3.3 Types of Digital Filter
	2.4 Spectral Analysis
	2.4.1 Discrete Fourier Transform
	2.4.2 Fast Fourier Transform
	2.5 Digital Filtering in Protection Relays
	2.5.1 Design Constraints
	2.5.2 Real-Time Considerations
	2.6 Further Reading
	3. Digital Communications and Fibre Optics
	3.0 Introduction
	3.1 Digital Data Transmission
	3.1.1 Introduction
	3.1.2 Simplex, Half Duplex and Full Duplex Transmission
	3.1.3 Asynchronous and Synchronous Transmission
	3.1.4 Error Handling
	3.1.5 Protocols and Standards
	3.1.6 Control System Communication Media and Configurations
	3.2 Fibre Optic Communications
	3.2.1 Introduction
	3.2.2 Fibre Optics Basics
	3.2.3 Communications Applications in Power Systems
	3.3 Further Reading
	4. Numeric Protection
	4.0 Introduction
	4.1 Numeric Relay Hardware
	4.1.1 Typical Relay Hardware Structure
	4.1.2 Relay Interfaces
	4.1.3 Relay Operating Environment
	4.2 Numeric Relay Algorithms
	4.2.1 Overcurrent Relays
	4.2.2 Distance Relays
	4.2.3 Directional Comparison Relays
	4.2.4 Differential Relays
	4.3 Fault Location
	4.3.1 Introduction
	4.3.2 Fault Location Using Apparent Reactance
	4.3.3 Compensation for Remote End Infeed
	4.3.4 Accurate Compensation for Shunt Capacitance
	4.3.5 Hardware for Fault Locators - Fault Recorders
	4.3.6 Phasor Extraction
	4.4 Software Considerations
	4.5 Numeric Relay Testing
	4.5.1 Introduction
	4.5.2 Relay Test Hardware
	4.5.3 Digital Power System Fault Simulation
	4.6 References
	4.7 Further Reading
	4.8 Appendix: Typical Numeric Relay Specifications
	4.8.1 Electrical Environment
	4.8.2 Insulation
	4.8.3 Electromagnetic Compatibility
	5. Coordinated Control
	5.0 Introduction
	5.1 Conventional Control Systems
	5.1.1 Functions and Design
	5.1.2 Disadvantages of Using Traditional Technology
	5.2 Concepts of Modern Coordinated Control Systems
	5.2.1 System Architecture (Distributed Processing)
	5.2.2 Numeric Technology
	5.3 System Functionality
	5.3.1 Bay Level
	5.3.2 Substation Level
	5.4 Man-Machine Interfaces (MMIs)
	5.4.1 Bay Level
	5.4.2 Substation Level
	5.4.3 Off-Line Applications
	5.5 Advantages of Coordinated Control Systems
	Glossary
	Index
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