The art and science of protective relaying

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• 1. The philosophy of protective relaying
  
  
  What is protective relaying?
  
  
  The function of protective relaying
  
  
  Fundamental principles of protective relaying
  
  
  - primary relaying
  
  
  - back-up relaying
  
  
  - protection against other abnormal conditions
  
  
  Functional characteristics of protective relaying
  
  
  - sensitivity, selectivity, and speed
  
  
  - reliability
  
  
  How do protective relays operate?


• 2. Fundamental relay-operating principles and characteristics
  
  
  General considerations
  
  
  - operating principles
  
  
  - definitions of operation
  
  
  - operation indicators
  
  
  - seal-in and holding coils, and seal-in relays
  
  
  - adjustment of pickup or reset
  
  
  - time delay and its definitions
  
  
  Single-quantity relays of the electromagnetic-attraction type
  
  
  - operating principle
  
  
  - ratio of reset to pickup
  
  
  - tendency toward vibration
  
  
  Directional relays of the electromagnetic attraction type
  
  
  - operating principle
  
  
  - efficiency
  
  
  - ratio of continuous thermal capacity to pickup
  
  
  Induction-type relays-general operating principles
  
  
  - the production of actuating force
  
  
  - types of actuating structure


• Single-quantity induction relays
  
  
  - torque control
  
  
  - effect of frequency
  
  
  - effect of d-c offset
  
  
  - ratio of reset to pickup


• Directional induction relays
  
  
  - torque relations in terms of actuating quantities
  
  
  - the significance of the term "directional"
  
  
  - the polarizing quantity of a directional relay
  
  
  - the operating characteristic of a directional relay
  
  
  - the "constant-product" characteristic
  
  
  - effect of d-c offset and other transients
  
  
  The universal relay-torque equation


• 3. Current, voltage, directional, current (or voltage)-balance, and differential relays
  
  
  General protective-relay features
  
  
  Overcurrent, undercurrent, overvoltage, and undervoltage relays
  
  
  D-C directional relays
  
  
  A-C directional relays
  
  
  Current (or voltage) - balance relays
  
  
  Differential relays


• 4. Distance relays
  
  
  The impedance-type distance relay
  
  
  The modified impedance-type distance relay
  
  
  The reactance-type distance relay
  
  
  The mho-type distance relay
  
  
  General considerations applicable to all distance relays


• 5. Wire-pilot relays
  
  
  Why current-differential relaying is not used
  
  
  Purpose of a pilot
  
  
  Tripping and blocking pilots
  
  
  D-C wire-pilot relaying
  
  
  Additional fundamental considerations
  
  
  A-C wire-pilot relaying


• 6. Carrier-current-pilot and microwave-pilot relays
  
  
  The carrier-current pilot
  
  
  The microwave pilot
  
  
  Phase-comparison relaying
  
  
  Directional-comparison relaying
  
  
  Looking ahead


• 7. Current transformers
  
  
  Types of current transformers
  
  
  Calculation of ct accuracy
  
  
  Polarity and connections


• 8. Voltage transformers
  
  
  Accuracy of potential transformers
  
  
  Capacitance potential devices
  
  
  The use of low-tension voltage
  
  
  Polarity and connections


• 9. Methods for analyzing generalizing, and visualizing relay response
  
  
  The R-X diagram
  
  
  Short circuits
  
  
  Power swings and loss of synchronism
  
  
  Response of polyphase directional relays to positive- and negative-phase-sequence volt-amperes
  
  
  Response of single-phase directional relays to short circuits
  
  
  Phase-sequence filters


• 10 A-C generator and motor protection
  
  
  Generator protection


• 11. Transformer protection
  
  
  Power transformers and power autotransformers
  
  
  Step voltage regulators
  
  
  Grounding transformers
  
  
  Electric arc-furnace transformers
  
  
  Power-rectifier transformers


• 12 bus protection
  
  
  Protection by back-up relays
  
  
  The fault bus1
  
  
  Directional-comparison relaying
  
  
  Current-differential relaying with overcurrent relays
  
  
  Partial-differential relaying
  
  
  Current-differential relaying with percentage-differential relays
  
  
  Voltage-differential relaying with "linear couplers"
  
  
  Current-differential relaying with overvoltage relays
  
  
  Combined power-transformer and bus protection
  
  
  The value of bus sectionalizing
  
  
  Back-up protection for bus faults
  
  
  Grounding the secondaries of differentially connected ct's
  
  
  Once-a-shift testing of differential-relaying equipment


• 13. Line protection with overcurrent relays
  
  
  How to set inverse-time-overcurrent relays for coordination
  
  
  Arc and ground resistance
  
  
  Effect of loop circuits on overcurrent relay adjustments
  
  
  Effect of system on choice of inverseness of relay characteristic
  
  
  The use of instantaneous overcurrent relays
  
  
  An incidental advantage of instantaneous overcurrent relaying
  
  
  Overreach of instantaneous overcurrent relays
  
  
  The directional feature
  
  
  Use of two versus three relays for phase-fault protection
  
  
  Single-phase versus polyphase directional-overcurrent relays
  
  
  How to prevent single-phase directional overcurrent-relay misoperation during ground faults
  
  
  Adjustment of ground versus phase relays
  
  
  Effect of limiting the magnitude of ground-fault current
  
  
  Transient ct errors
  
  
  Detection of ground faults in ungrounded systems
  
  
  Effect of ground-fault neutralizers on line relaying
  
  
  The effect of open phases not accompanied by a short circuit
  
  
  The effect of open phases accompanied by short circuits
  
  
  Polarizing the directional units of ground relays
  
  
  Negative-phase-sequence directional units for ground-fault relaying
  
  
  Current-balance and power-balance relaying
  
  
  Automatic reclosing
  
  
  Restoration of service to distribution feeders after prolonged outages
  
  
  Coordinating with fuses
  
  
  A-C and capacitor tripping


• 14. Line protection with distance relays
  
  
  The choice between impedance, reactance, or mho
  
  
  The adjustment of distance relays
  
  
  The effect of arcs on distance-relay operation
  
  
  The effect of intermediate current sources on distance-relay operation
  
  
  Overreach because of offset current waves
  
  
  Overreach of ground distance relays for phase faults
  
  
  Use of low-tension voltage
  
  
  Use of low-tension current
  
  
  Effect of power-transformer magnetizing-current inrush on distance-relay operation
  
  
  The connections of ground distance relays
  
  
  Operation when PT fuses blow
  
  
  Purposeful tripping on loss of synchronism
  
  
  Blocking tripping on loss of synchronism
  
  
  Automatic reclosing
  
  
  Effect of presence of expulsion protective gaps
  
  
  Effect of a series capacitor
  
  
  Cost-reduction schemes for distance relaying
  
  
  Electronic distance relays


• 15. Line protection with pilot relays
  
  
  Wire-pilot relaying
  
  
  Obtaining adequate sensitivity
  
  
  The protection of multiterminal lines
  
  
  Current-transformer requirements
  
  
  Back-up protection
  
  
  Carrier-current-pilot relaying
  
  
  Phase comparison
  
  
  Directional comparison
  
  
  Combined phase and directional comparison
  
  
  All-electronic directional-comparison equipment
  
  
  High-speed reclosing

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Interior Electrical Systems

File Type:- pdf


File Size:- 1.78 MB


Pages:- 279 pages

Contents:-

• 1. General


• 1-1 PURPOSE
  
  
  1-2 SCOPE
  
  
  1-3 REFERENCES
  
  
  1-4 CODES AND STANDARDS
  
  
  1-5 SYMBOLS
  
  
  1-6 APPLICABILITY
  
  
  1-7 MANUAL CONTENT AND ORGANIZATION


• PRELIMINARY AND DETAILED DESIGN ANALYSIS
  
  
  2-1 PRELIMINARY DESIGN
  
  
  2-1.1 Principal Points of Contact
  
  
  2-1.2 Preliminary Design Guidance for Interior Electrical Systems
  
  
  2-1.3 Unified Facilities Guide Specifications
  
  
  2-2 ELECTRICAL LOAD CRITERIA
  
  
  2-3 OVERVIEW OF DETAILED ANALYSIS CRITERIA
  
  
  2-4 SHORT CIRCUIT ANALYSIS
  
  
  2-4.1 Analysis and Equipment Criteria
  
  
  2-4.2 Short Circuit Sources
  
  
  2-4.3 Symmetrical Versus Asymmetrical Current
  
  
  2-4.4 Short Circuit Calculations
  
  
  2-5 POWER FLOW ANALYSIS
  
  
  2-6 VOLTAGE DROP ANALYSIS
  
  
  2-6.1 Voltage Drop Calculations
  
  
  2-6.2 Motor Starting Studies
  
  
  2-7 ELECTRICAL COORDINATION
  
  
  2-8 POWER QUALITY AND HARMONIC DISTORTION
  
  
  2-9 LIGHTING
  
  
  2-10 ENERGY ANALYSIS
  
  
  2-10.1 Overview
  
  
  2-10.2 New Facility Criteria
  
  
  2-10.3 Existing Facilities
  
  
  2-10.4 Energy Efficiency Design Opportunities in the Electrical System
  
  
  2-11 LIFE-CYCLE COST ANALYSIS
  
  
  2-12 ELECTRICAL DRAWINGS
  
  
  2-12.1 Introduction
  
  
  2-12.2 One-Line Diagrams
  
  
  2-12.3 Switchgear Lineups
  
  
  2-12.4 MCC Layouts
  
  
  2-12.5 Grounding
  
  
  2-12.6 Control Panel Wiring Diagrams
  
  
  2-12.7 Control Schematics
  
  
  2-12.8 Miscellaneous Interconnection Diagrams
  
  
  2-12.9 Equipment Layouts with Conduit or Cable Tray
  
  
  2-12.10 Panel Schedules
  
  
  2-12.11 Lighting and Receptacle Layouts
  
  
  2-12.12 Motor List
  
  
  2-12.13 Conduit or Cable Schedule


• GENERAL POWER SYSTEM CRITERIA
  
  
  3-1 CHARACTERISTICS
  
  
  3-1.1 Voltage
  
  
  3-1.2 Frequency
  
  
  3-1.3 Power Factor
  
  
  3-1.4 Neutral Conductor Grounding
  
  
  3-2 NORMAL POWER SOURCE
  
  
  3-3 ALTERNATE AND BACKUP POWER SOURCE
  
  
  3-4 SERVICES


• POWER DISTRIBUTION AND UTILIZATION-TRANSFORMERS
  
  
  4-1 RATINGS
  
  
  4-1.1 Introduction
  
  
  4-1.2 Voltage and Current
  
  
  4-1.3 Temperature and kVA
  
  
  4-1.4 Impedance
  
  
  4-1.5 Number of Phases
  
  
  4-1.6 Transformer Taps
  
  
  4-1.7 Noise
  
  
  4-1.8 Basic Impulse Insulation Levels (BILs)
  
  
  4-2 LOW VOLTAGE TRANSFORMERS
  
  
  4-3 MEDIUM VOLTAGE TRANSFORMERS
  
  
  4-4 OTHER TRANSFORMERS
  
  
  4-4.1 Isolation Transformers
  
  
  4-4.2 Buck-Boost Transformers
  
  
  4-4.3 K-Factor Transformers
  
  
  4-4.4 Specialty Transformers
  
  
  4-5 TRANSFORMER INSTALLATION CRITERIA
  
  
  4-5.1 Introduction
  
  
  4-5.2 Dry-Type Transformers
  
  
  4-5.3 Less-Flammable, Liquid-Insulated, and Oil-Insulated Transformers
  
  
  4-5.4 Fire Protection Criteria
  
  
  4-6 TRANSFORMER SIZING
  
  
  4-7 INFORMATION SOURCES


• CHAPTER 5 POWER DISTRIBUTION AND UTILIZATION-SWITCHGEAR, LOAD CENTERS, AND BREAKERS


• 5-1 SERVICE ENTRANCE
  
  
  5-2 SWITCHGEAR AND SWITCHBOARDS GENERAL CRITERIA
  
  
  5-3 HIGH VOLTAGE SWITCHGEAR
  
  
  5-4 MEDIUM VOLTAGE SWITCHGEAR
  
  
  5-4.1 Ratings
  
  
  5-4.2 Low Voltage Conductors in Medium Voltage Switchgear
  
  
  5-5 LOW VOLTAGE BREAKERS AND PANELS
  
  
  5-6 MOTOR CONTROL CENTERS
  
  
  5-7 DISCONNECT SWITCHES
  
  
  5-8 CIRCUIT LOCKOUT REQUIREMENTS
  
  
  5-9 INFORMATION SOURCES


• CHAPTER 6 POWER DISTRIBUTION AND UTILIZATION-RACEWAY AND WIRING


• 6-1 RACEWAY CRITERIA
  
  
  6-2 WIRING SYSTEM CRITERIA
  
  
  6-3 SIZING WIRING SYSTEMS FOR ENERGY SAVINGS
  
  
  6-4 CONVENIENCE OUTLETS AND RECEPTACLES
  
  
  6-5 WIRING FOR TEMPORARY POWER AND LIGHTING
  
  
  6-6 ACCEPTANCE TESTING OF WIRING SYSTEMS


• CHAPTER 7 POWER DISTRIBUTION AND UTILIZATION-MOTORS AND MOTOR CONTROL CIRCUITS


• 7-1 BASIC MOTOR CRITERIA
  
  
  7-2 MOTOR CONTROL CIRCUITS
  
  
  7-3 ADJUSTABLE SPEED DRIVES


• CHAPTER 8 POWER DISTRIBUTION AND UTILIZATION-OTHER DESIGN CRITERIA


• 8-1 ELECTRICAL EQUIPMENT CLEARANCES AND GUARDS
  
  
  8-1.1 Background
  
  
  8-1.2 Equipment Rated 600 Volts and Lower
  
  
  8-1.3 Equipment Rated Above 600 Volts
  
  
  8-2 ENCLOSURES
  
  
  8-3 HAZARDOUS LOCATIONS
  
  
  8-4 400-HERTZ DISTRIBUTION SYSTEMS
  
  
  8-5 METERING
  
  
  8-6 POWER FACTOR CORRECTION


• CHAPTER 9 ELECTRICAL SYSTEM PROTECTION AND COORDINATION


• 9-1 PROTECTION SYSTEM DESIGN
  
  
  9-2 ELECTRICAL COORDINATION ANALYSIS CRITERIA
  
  
  9-2.1 Introduction
  
  
  9-2.2 Coordination Study Description
  
  
  9-2.3 Coordination Time Intervals
  
  
  9-2.4 Pickup Current
  
  
  9-2.5 Coordination Curves
  
  
  9-2.6 Coordination Analysis
  
  
  9-2.7 Coordination Study Report
  
  
  9-3 PROTECTIVE RELAYS
  
  
  9-4 INSTRUMENT TRANSFORMERS
  
  
  9-4.1 Background
  
  
  9-4.2 Current Transformers
  
  
  9-4.3 Potential Transformers
  
  
  9-5 FUSES
  
  
  9-6 OVERLOAD RELAYS
  
  
  9-7 CIRCUIT BREAKERS
  
  
  9-8 PROTECTIVE DEVICE DESIGNATIONS
  
  
  9-9 INFORMATION SOURCES


• CHAPTER 10 GROUNDING, BONDING, AND LIGHTNING PROTECTION


• 10-1 INTRODUCTION
  
  
  10-2 NEC GROUNDING AND BONDING REQUIREMENTS
  
  
  10-3 STATIC PROTECTION
  
  
  10-4 COMMUNICATIONS SYSTEMS GROUNDING AND BONDING
  
  
  10-4.1 Introduction
  
  
  10-4.2 Connection to the Grounding Electrode
  
  
  10-4.3 Commercial Building Grounding and Bonding Requirements for Telecommunications
  
  
  10-5 LIGHTNING PROTECTION
  
  
  10-6 INFORMATION SOURCES


• CHAPTER 11 SURGE PROTECTION


• 11-1 INTRODUCTION
  
  
  11-2 SURGE PROTECTION DESIGN
  
  
  11-2.1 Parallel Versus Series Approach
  
  
  11-2.2 Multiple Layer Protection Design
  
  
  11-3 INSTALLATION CRITERIA
  
  
  11-3.1 Minimizing Lead Length for Parallel Surge Protectors
  
  
  11-3.2 Breaker Connection
  
  
  11-3.3 Grounding
  
  
  11-3.4 Acceptance Tests
  
  
  11-3.5 Periodic Maintenance
  
  
  11-4 SURGE PROTECTION FOR COMMUNICATIONS AND RELATED SYSTEMS


• CHAPTER 12 POWER SYSTEM QUALITY


• 12-1 INTRODUCTION
  
  
  12-2 UNBALANCED VOLTAGES
  
  
  12-3 HARMONIC DISTORTION EVALUATION
  
  
  12-4 HARMONIC CURRENT EFFECTS ON TRANSFORMERS
  
  
  12-5 POWER QUALITY DESIGN
  
  
  12-6 NONLINEAR LOAD DESIGN CONSIDERATIONS
  
  
  12-7 NEUTRAL CIRCUIT SIZING FOR NONLINEAR LOADS
  
  
  12-7.1 Potential Neutral Current Magnitudes
  
  
  12-7.2 Installation Design Criteria
  
  
  12-8 INFORMATION SOURCES


• CHAPTER 13 EMERGENCY AND STANDBY POWER SYSTEMS


• 13-1 ESTABLISHING THE NEED FOR BACKUP POWER
  
  
  13-2 CLASSIFYING EMERGENCY POWER LOADS
  
  
  13-3 ENGINE GENERATORS
  
  
  13-4 UPS SYSTEMS
  
  
  13-4.1 Introduction
  
  
  13-4.2 Selection and Performance
  
  
  13-4.3 Sizing
  
  
  13-4.4 Selection of a Large UPS System or Multiple Smaller UPS Systems


• 13-4.5 Design Criteria
  
  
  13-4.6 Site Survey for an Installation
  
  
  13-5 AUTOMATIC TRANSFER EQUIPMENT
  
  
  13-5.1 Introduction
  
  
  13-5.2 Transfer Methods
  
  
  13-5.3 Design Considerations
  
  
  13-5.4 Static Transfer Switches
  
  
  13-5.5 Sizing
  
  
  13-5.6 Effect of Motor Loads
  
  
  13-5.7 Maintaining Ground Fault Protection
  
  
  13-5.8 Additional System Design Considerations
  
  
  13-5.9 Information Sources


• CHAPTER 14 STATIONARY BATTERY SYSTEMS


• 14-1 STATIONARY BATTERIES
  
  
  14-1.1 Selection
  
  
  14-1.2 Battery Areas and Battery Racks
  
  
  14-1.3 Installation Design Considerations
  
  
  14-2 BATTERY CHARGERS
  
  
  14-3 BATTERY PROTECTION


• CHAPTER 15 LIGHTING


• 15-1 LIGHTING DESIGN CRITERIA


• CHAPTER 16 COMMUNICATIONS AND INFORMATION SYSTEMS


• 16-1 INTRODUCTION
  
  
  16-2 ARMY DESIGN CRITERIA
  
  
  16-3 NAVY DESIGN CRITERIA
  
  
  16-4 AIR FORCE DESIGN CRITERIA


• CHAPTER 17 AUXILIARY SYSTEMS


• 17-1 FIRE ALARM AND DETECTION SYSTEMS
  
  
  17-2 SECURITY SYSTEMS
  
  
  17-3 TELEVISION SYSTEMS
  
  
  17-4 CLOCK SYSTEMS
  
  
  17-5 ENERGY MANAGEMENT AND CONTROL SYSTEMS


• CHAPTER 18 FACILITY-SPECIFIC DESIGN CRITERIA


• 18-1 MEDICAL FACILITIES
  
  
  18-2 POWER DISTRIBUTION FOR AIRCRAFT HANGARS (SHELTERS)
  
  
  18-3 HIGH-ALTITUDE ELECTROMAGNETIC PULSE (HEMP) AND TEMPEST PROTECTION
  
  
  18-4 SEISMICALLY QUALIFIED DESIGNS
  
  
  18-5 TROPICAL ENGINEERING
  
  
  18-6 ARCTIC ENGINEERING
  
  
  18-7 GENERAL FACILITY TYPES

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