Handbook of Electrical Engineering

Alan L. Sheldrake is the author of Handbook of Electrical Engineering: For Practitioners in the Oil, Gas and Petrochemical Industry, published by Wiley.

• Foreword xixPreface xxiAcknowledgements xxiiiAbout the Author xxv1 Estimation of Plant Electrical Load 11.1 Preliminary Single-Line Diagrams 11.2 Load Schedules 21.3 Determination of Power Supply Capacity 81.4 Standby Capacity of Plain Cable Feeders and Transformer Feeders 121.5 Rating of Generators in Relation to their Prime Movers 131.6 Rating of Motors in Relation to their Driven Machines 131.7 Development of Single-Line Diagrams 141.8 Coordination with other Disciplines 16Reference 182 Gas Turbine Driven Generators 192.1 Classification of Gas Turbine Engines 192.2 Energy Obtained from a Gas Turbine 232.3 Power Output from a Gas Turbine 362.4 Starting Methods for Gas Turbines 392.5 Speed Governing of Gas Turbines 392.6 Mathematical Modelling of Gas Turbine Speed Governing Systems 52References 59Further Reading 593 Synchronous Generators and Motors 613.1 Common Aspects Between Generators and Motors 613.2 Simplified Theory of Operation of a Generator 613.3 Phasor Diagram of Voltages and Currents 643.4 The Derived Reactances 653.4.1 Sensitivity of X md , X a, X f and X kd to Changes in Physical dimensions 673.5 Active and Reactive Power Delivered from a Generator 683.6 The Power Versus Angle Chart of a Salient Pole Generator 723.7 Choice of Voltages for Generators 733.8 Typical Parameters of Generators 733.9 Construction Features of High Voltage Generators and Induction Motors 78References 814 Automatic Voltage Regulation 834.1 Modern Practice 834.2 IEEE Standard AVR Models 89Reference 975 Induction Motors 995.1 Principle of Operation of the Three-Phase Motor 995.2 Essential Characteristics 1005.3 Construction of Induction Motors 1195.4 Derating Factors 1215.5 Matching the Motor Rating to the Driven Machine Rating 1215.6 Effect of the Supply Voltage on Ratings 1225.7 Effect of the System Fault Level 1235.8 Cable Volt-drop Considerations 1235.9 Critical Times for Motors 1255.10 Methods of Starting Induction Motors 125References 1296 Transformers 1316.1 Operating Principles 1316.2 Efficiency of a Transformer 1346.3 Regulation of a Transformer 1356.4 Three-Phase Transformer Winding Arrangements 1366.5 Construction of Transformers 1376.6 Transformer Inrush Current 140References 1427 Switchgear and Motor Control Centres 1437.1 Terminology in Common Use 1437.2 Construction 1447.3 Switching Devices 1547.4 Fuses for Motor Control Centre Outgoing Circuits 1567.5 Safety Interlocking Devices 1577.6 Control and Indication Devices 1587.7 Moulded Case Circuit Breakers 162References 1728 Fuses 1738.1 General Comments 1738.2 Operation of a Fuse 1748.3 Influence of the Circuit X-to-R Ratio 1748.4 The I 2 t Characteristic 176References 1819 Cables, Wires and Cable Installation Practices 1839.1 Electrically Conducting Materials used in the Construction of Cables 1839.2 Electrically Non-Conducting Materials used in the Construction of Cables 1879.3 Composition of Power and Control Cables 1919.4 Current Ratings of Power Cables 1989.5 Cables with Enhanced Performance 244Reference 24710 Hazardous Area Classification and the Selection of Equipment 24910.1 Historical Developments 24910.2 Present Situation 24910.3 Elements of Hazardous Area Classification 25110.4 Hazardous Area Zones 25310.5 Types of Protection for Hazardous Areas 25410.6 Types of Protection for Ingress of Water and Solid Particles 26010.7 Certification of Hazardous Area Equipment 26510.8 Marking of Equipment Nameplates 266References 266Further Reading 26611 Fault Calculations and Stability Studies 26911.1 Introduction 26911.2 Constant Voltage Source – High Voltage 26911.3 Constant Voltage Source – Low Voltage 27111.4 Non-Constant Voltage Sources – All Voltage Levels 27311.5 Calculation of Fault Current due to Faults at the Terminals of a Generator 27411.6 Calculate the Sub-Transient symmetrical RMS Fault Current Contributions 27911.7 Application of the Doubling Factor to Fault Current I′′frms found in 11.6 28711.8 Computer Programs for Calculating Fault Currents 29211.9 The use of Reactors 29411.10 Some Comments on the Application of IEC60363 and IEC 60909 30011.11 Stability Studies 300References 308Further Reading 30912 Protective Relay Coordination 31112.1 Introduction to Overcurrent Coordination 31112.2 Generator Protection 31312.3 Emergency Diesel Generators 32512.4 Feeder Transformer Protection 32612.5 Feeder Cable Protection 33212.6 Busbar Protection in Switchboards 33412.7 High Voltage Induction Motor Protection 33612.8 Low Voltage Induction Motor Protection 34212.9 Low Voltage Static Load Protection 34512.10 Mathematical Equations for Representing Standard, Very and Extremely Inverse Relays 346References 34913 Earthing and Screening 35113.1 Purpose of Earthing 35113.2 Site Locations 35313.3 Design of Earthing Systems 35613.4 Construction Details Relating to Earthing 37113.5 Screening and Earthing of Cables used in Electronic Circuits 373References 38314 Variable Speed Electrical Drivers 38514.1 Introduction 38514.2 Group 1 Methods 38814.3 Group 2 Methods 39214.4 Variable Speed DC Motors 39414.5 Electrical Submersible Pumps 39414.6 Control Systems for AC Motors 397References 40015 Harmonic Voltages and Currents 40115.1 Introduction 40115.2 Rectifiers 40215.3 Harmonic Content of the Supply Side Currents 41315.4 Inverters 42115.5 Filtering of Power Line Harmonics 42915.6 Protection, Alarms and Indication 433References 43316 Computer Based Power Management Systems 43516.1 Introduction 43516.2 Typical Configurations 43516.3 Main Functions 43617 Uninterruptible Power Supplies 44917.1 AC Uninterruptible Power Supplies 44917.2 DC Uninterruptible Power Supplies 45117.3 Redundancy Configurations 457References 45818 Miscellaneous Subjects 45918.1 Lighting Systems 45918.2 Navigation Aids 46318.3 Cathodic Protection 467References 46819 Preparing Equipment Specifications 46919.1 The Purpose of Specifications 46919.2 A Typical Format for a Specification 47020 Summary of the Generalised Theory of Electrical Machines as Applied to Synchronous Generators and Induction Motors 47920.1 Introduction 47920.2 Synchronous Generator 48020.3 Some Notes on Induction Motors 49020.3.1 Derived reactances 49120.3.2 Application of three-phase short circuit 49120.3.3 Derived reactances and time constants for an induction motor 49320.3.4 Derivation of an equivalent circuit 49520.3.5 ‘Re-iteration or recapitulation’ 49620.3.6 Contribution of three-phase short-circuit current from induction motor 501References 504Further Reading 505Appendix A Abbreviations Commonly used in Electrical Documents 507Appendix B A List of Standards Often Used for Designing Electrical Systems and for Specifying Equipment 517B. 1 International Electro-technical Commission (Europe) 517B. 2 Institute of Petroleum (UK) 525B. 3 International Standards Organisation (Worldwide) 526B. 4 British Standards Institution (UK) 526B. 5 American Petroleum Institute (USA) 530B. 6 Counseil International des Grands Reseaux Electriques (France) 530B. 7 Engineering Equipment and Materials Users Association (UK) 530B. 8 Electricity Council (UK) 531B. 9 Verband Deutscher Electrechniker (Germany) 531B.10 Institute of Electronic and Electrical Engineers Inc. (USA) 531B.11 Miscellaneous References from the UK 532Appendix C Numbering System for Protective Devices, Control and Indication Devices for Power Systems 533C. 1 Application of Protective Relays, Control and Alarm Devices for Power System Circuits 533C.1.1 Notes to sub-section C. 1 535C. 2 Electrical Power System Device Numbers and Functions 536Appendix D Under-Frequency and Over-Temperature Protection of Gas-Turbine Driven Generators 539Appendix E List of Document Types to be Produced During a Project 545E. 1 Contractors Documents 546E. 2 Manufacturers Documents 549Appendix F Worked Example for Calculating the Performance of a Gas Turbine 551F.1 The Requirements and Data Given 551F.2 Basic Requirements 551F.3 Detailed Requirements 552F.4 Basic Solutions 552F.5 Detailed Solutions 553Appendix G Worked Example for the Calculation of Volt-drop in a Circuit Containing an Induction Motor 559G.1 Introduction 559Appendix H Worked Example for the Calculation of Earthing Current and Electric Shock Hazard Potential Difference in a Rod and Grid Earthing System 585H.1 Worked Example 585Appendix I Conversion Factors for the SI System of Units 597I.1 Fundamental SI Units 597I.2 Derived Non-electrical Units 597I.3 Derived Electrical Units 598I.4 Conversions 598I.5 International Standards Organisation (ISO) Conditions 605I.6 Standard Temperature and Pressure (STP) Conditions 605I.7 Regularly Used Constants 605I.8 Regularly Used Prefixes 606I.9 References 606Index 607

"...an excellent reference...with many worked out examples and loads of practical real world calculations, this well laid out book would be an invaluable guide for new power system engineers...and also provide experienced engineers a way to check their designs or find out about other areas." (IEEE Electrical Insulation Magazine, January/February 2004)