Electronic Circuits - Fundamentals and Applications

Preface
This is the book that I wish I had when I first started exploring electronics nearly half a century ago. In those days, transistors were only just making their debut and integrated circuits were  completely unknown. Of course, since then much has changed but, despite all of the changes, the world of electronics remains a fascinating one. And, unlike most other advanced technological disciplines, electronics is still something that you can ‘do’ at home with limited resources and with a minimal outlay. A soldering iron, a multi-meter, and a handful of components are all that you need to get started. Except, of course, for some ideas to get you started—and that’s exactly where this book comes in!


 The book has been designed to help you understand how electronic circuits work. It will provide you with the basic underpinning knowledge necessary to appreciate the operation of a wide range of electronic circuits including amplifiers, logic circuits, power supplies and oscillators. 


 The book is ideal for people who are studying electronics for the first time at any level including a wide range of school and college courses. It is equally well suited to those who may be returning to study or who may be studying independently as well as those who may need a quick refresher. The book has 19 chapters, each dealing with a particular topic, and eight appendices containing useful information. The approach is topic-based rather than syllabus-based and each major topic looks at a particular application of electronics. The relevant theory is introduced on a progressive basis and delivered in manageable chunks.

 In order to give you an appreciation of the solution of simple numerical problems related to the operation of basic circuits, worked examples have been liberally included within the text. In addition, a number of problems can be found at the end of each chapter and solutions are provided at the end of the book. You can use these end-ofchapter problems to check your understanding and also to give you some experience of the ‘short answer’ questions used in most in-course assessments. For good measure, we have included 70 revision problems in Appendix 2. At the end of the book you will find 21 sample coursework assignments. These should give you plenty of ‘food for thought’ as well as offering you some scope for further experimentation. It is not envisaged that you should complete all of these assignments and a carefully chosen selection will normally suffice. If you are following a formal course, your teacher or lecturer will explain how these should be tackled and how they can contribute to your course assessment. While the book assumes no previous knowledge of electronics you need to be able to manipulate basic formulae and understand some simple trigonometry in order to follow the numerical examples. A study of mathematics to GCSE level (or equivalent) will normally be adequate to satisfy this requirement. However, for those who may need a refresher or have had previous problems with mathematics, Appendix 6 will provide you with the underpinning mathematical knowledge required.

 In the later chapters of the book, a number of representative circuits (with component values) have been included together with sufficient information to allow you to adapt and modify the circuits for your own use. These circuits can be used to form the basis of your own practical investigations or they can be combined together in more complex circuits.

 Finally, you can learn a great deal from building, testing and modifying simple circuits. To do this you will need access to a few basic tools and some minimal test equipment. Your first purchase should be a simple multi-range meter, either digital or analogue. This instrument will allow you to measure the voltages and currents present so that you can compare them with the predicted values. If you are attending a formal course of instruction and have access to an electronics laboratory, do make full use of it!

A note for teachers and lecturers 
The book is ideal for students following formal courses (e.g. GCSE, AS, A-level, BTEC, City and Guilds, etc.) in schools, sixth-form colleges, and further/higher education colleges. It is equally well suited for use as a text that can support distance or flexible learning and for those who may need a ‘refresher’ before studying electronics at a higher level.

 While the book assumes little previous knowledge students need to be able to manipulate basic formulae and understand some simple trigonometry to follow the numerical examples. A study of mathematics to GCSE level (or beyond) will normally be adequate to satisfy this requirement.

 However, an appendix has been added specifically to support students who may have difficulty with mathematics. Students will require a scientific calculator in order to tackle the end-ofchapter problems as well as the revision problems that appear at the end of the book.

 We have also included 21 sample coursework assignments. These are open-ended and can be modified or extended to suit the requirements of the particular awarding body. The assignments have been divided into those that are broadly at Level 2 and those that are at Level 3. In order to give reasonable coverage of the subject, students should normally be expected to complete between four and five of these assignments. Teachers can differentiate students’ work by mixing assignments from the two levels. In order to challenge students, minimal information should be given to students at the start of each assignment. The aim should be that of giving students ‘food for thought’ and encouraging them to develop their own solutions and interpretation of the topic.

 Where this text is to be used to support formal teaching it is suggested that the chapters should be followed broadly in the order that they appear with the notable exception of Chapter 14. Topics from this chapter should be introduced at an early stage in order to support formal lab work. Assuming a notional delivery time of 4.5 hours per week, the material contained in this book (together with supporting laboratory exercises and assignments) will require approximately two academic terms (i.e. 24 weeks) to deliver in which the total of 90 hours of study time should be divided equally into theory (supported by problem solving) and practical (laboratory and assignment work). The recommended four or five assignments will require about 25 to 30 hours of student work to complete. Finally, when constructing a teaching programme it is, of course, essential to check that you fully comply with the requirements of the awarding body concerning assessment and that the syllabus coverage is adequate. 

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Lightning Protection

Contents

List of contributors xxvii

Preface xxix

Acknowledgements xxxi

1 Benjamin Franklin and lightning rods 1

E. Philip Krider

1.1 A Philadelphia story 3

1.2 The French connection 5

1.3 Experiments in colonial America 6

1.4 First protection system 7

1.5 Improvements 9

1.6 ‘Snatching lightning from the sky’ 12

Acknowledgement 13

References 13

2 Lightning parameters of engineering interest 15

Vernon Cooray and Mahendra Fernando

2.1 Introduction 15

2.2 Electric fields generated by thunderclouds 19

2.3 Thunderstorm days and ground flash density 23

2.4 Number of strokes and time interval between strokes

in ground flashes25

2.4.1 Number of strokes per flash 28

2.4.2 Interstroke interval 30

2.5 Number of channel terminations in ground flashes 31

2.6 Occurrence of surface flash over 34

2.7 Lightning leaders 36

2.7.1 Speed of stepped leaders 36

2.7.2 Speed of dart leaders 37

2.7.3 Electric fields generated by stepped leaders 39

2.7.4 Electric fields generated by dart leaders 40

2.7.5 Speed of connecting leaders 44

2.7.6 Currents in connecting leaders 45

2.8 Current parameters of first and subsequent returnstrokes 47

2.8.1 Berger’s measurements 50

2.8.2 Garbagnati and Piparo’s measurements 51

2.8.3 Eriksson’s measurements 51

2.8.4 Analysis of Andersson and Eriksson 53

2.8.5 Measurements of Takami and Okabe 53

2.8.6 Measurements of Visacro and colleagues 54

2.8.7 Summary of current measurements 54

2.9 Statistical representation of lightning current parameters 55

2.9.1 Correlation between different current parameters57

2.9.2 Effect of tower height 60

2.9.3 Mathematical representation of current waveforms67

2.9.3.1 Current waveform recommended by the CIGRE study group67

2.9.3.2 Analytical form of the current used in the

International Electrotechnical

Commission standard 70

2.9.3.3 Analytical expression of Nucci and colleagues 71

2.9.3.4 Analytical expression of Diendorfer and Uman 71

2.9.3.5 Analytical expression of Delfino and colleagues72

2.9.3.6 Analytical expression of Cooray and colleagu72

2.9.4 Current wave shapes of upward-initiated flashes 72

2.10 Electric fields from first and subsequent strokes74

2.11 Peak electric radiation fields of first and subsequent strokes 81

2.12 Continuing currents 84

2.13 M-components 88

References 88

3 Rocket-triggered lightning and new insights into lightning

protection gained from triggered-lightning experiments97

V.A. Rakov

3.1 Introduction 97

3.2 Triggering techniques 98

3.2.1 Classical triggering 98

3.2.2 Altitude triggering 103

3.2.3 Triggering facility at Camp Blanding, Florida 105

3.3 Overall current waveforms 107

3.3.1 Classical triggering 107

3.3.2 Altitude triggering 109

3.4 Parameters of return-stroke current waveforms 110

3.5 Return-stroke current peak versus grounding conditions 122

3.6 Characterization of the close lightning electromagnetic environment128

3.7 Studies of interaction of lightning with various objects and systems131

3.7.1 Overhead power distribution lines 131

3.7.1.1 Nearby strikes 131

3.7.1.2 Direct strikes 135

3.7.2 Underground cables 143

3.7.3 Power transmission lines 143

3.7.4 Residential buildings 144

3.7.5 Airport runway lighting system 144

3.7.6 Miscellaneous experiments 149

3.8 Concluding remarks 150

References 150

Bibliography 159

4 Attachment of lightning flashes to grounded structures 165

Vernon Cooray and Marley Becerra

4.1 Introduction 165

4.1.1 The protection angle method 166

4.1.2 The electro-geometrical method 168

4.1.3 The rolling sphere method 170

4.1.4 The mesh method 175

4.2 Striking distance to flat ground 176

4.2.1 Golde 177

4.2.2 Eriksson 177

4.2.3 Dellera and Garbagnati 179

4.2.4 Cooray and colleagues 179

4.2.5 Armstrong and Whitehead 180

4.3 Striking distance to elevated structures 182

4.3.1 Positive leader discharges 183

4.3.2 Leader inception models 186

4.3.2.1 The critical radius concept 186

4.3.2.2 Rizk’s generalized leader inception equation 190

4.3.2.3 Critical streamer length concept 194

4.3.2.4 Bazelyan and Raizer’s empirical leader model 195

4.3.2.5 Lalande’s stabilization field equation 196

4.3.2.6 The self-consistent leader inception model of

Becerra and Cooray197

4.4 The leader progression model 212

4.4.1 The basic concept of the leader progression model 212

4.4.2 The leader progression model of Eriksson 212

4.4.3 The leader progression model of Dellera and

Garbagnati215

4.4.4 The leader progression model of Rizk 217

4.4.5 Attempts to validate the existing leader progression models 220

4.4.6 Critical overview of the assumptions of leader progression models223

4.4.6.1 Orientation of the stepped leader 223

4.4.6.2 Leader inception criterion 224

4.4.6.3 Parameters and propagation of the upward

connecting leader225

4.4.6.4 Effects of leader branches and tortuosity 226

4.4.6.5 Thundercloud electric field 226

4.4.7 Becerra and Cooray leader progression model 227

4.4.7.1 Basic theory 227

4.4.7.2 Self-consistent lightning interception model

(SLIM)231

4.5 Non-conventional lightning protection systems 239

4.5.1 The early streamer emission concept 240

4.5.1.1 Experimental evidence in conflict with the concept of ESE 241

4.5.1.2 Theoretical evidence in conflict with the concept of ESE 243

4.5.2 The concept of dissipation array systems (DAS) 251

4.5.2.1 Experimental evidence against dissipation arrays 253

5 Protection against lightning surges 269

Rajeev Thottappillil and Nelson Theethayi

5.1 Introduction 269

5.1.1 Direct strike to power lines 269

5.1.2 Lightning activity in the vicinity of networks 270

5.2 Characteristics of lightning transients and their

impact on systems 273

5.2.1 Parameters of lightning current important for

surge protection design 274

5.2.1.1 Peak current 274

5.2.1.2 Charge transferred 274

5.2.1.3 Prospective energy 275

5.2.1.4 Waveshape 276

5.2.2 Parameters of lightning electric and magnetic

fields important for surge protection design276

5.3 Philosophy of surge protection 278

5.3.1 Surge protection as part of achieving

electromagnetic compatibility 278

5.3.1.1 Conductor penetration through a shield 279

5.3.2 Principle of surge protection 280

5.3.2.1 Gas discharge tubes (spark gaps) 282

5.3.2.2 Varistors 285

5.3.2.3 Diodes and thyristors 286

5.3.2.4 Current limiters 288

5.3.2.5 Isolation devices 290

5.3.2.6 Filters 291

5.3.2.7 Special protection devices used in power distribution networks 293

5.4 Effects of parasitic elements in surge protection and filter components 294

5.4.1 Capacitors 295

5.4.2 Inductors 297

5.4.3 Resistors 298

5.4.3.1 Behaviour of resistors at various frequencies 299

5.5 Surge protection coordination 302

References 303

6 External lightning protection system 307

Christian Bouquegneau

6.1 Introduction 307

6.2 Air-termination system 308

6.2.1 Location of air-terminations on the structure 308

6.2.1.1 Positioning of the air-termination system utilizing the rolling sphere method310

6.2.1.2 Positioning of the air-termination system utilizing the mesh method311

6.2.1.3 Positioning of the air-termination system utilizing the protection angle method313

6.2.1.4 Comparison of methods for the positioning of the air-termination system316

6.2.2 Construction of air-termination systems 316

6.2.3 Non-conventional air-termination systems 320

6.3 Down-conductor system 320

6.3.1 Location and positioning of down-conductors on the structure 320

6.3.2 Construction of down-conductor systems 322

6.3.3 Structure with a cantilevered part 325

6.3.4 Joints, connections and test joints in down-conductors 326

6.3.5 Lightning equipotential bonding 328

6.3.6 Current distribution in down-conductors 330

6.4 Earth-termination system 330

6.4.1 General principles 330

6.4.2 Earthing arrangements in general conditions 332

6.4.3 Examples of earthing arrangements in common small structures 335

6.4.4 Special earthing arrangements 341

6.4.4.1 Earth electrodes in rocky and sandy soils 341

6.4.4.2 Earth-termination systems in large areas 341

6.4.4.3 Artificial decrease of earth resistance 342

6.4.5 Effect of soil ionization and breakdown 343

6.4.6 Touch voltages and step voltages 343

6.4.6.1 Touch voltages 343

6.4.6.2 Step voltages 344

6.4.8 Measurement of soil resistivity and earth resistances 345

6.4.8.1 Measurement of soil resistivity 345

6.4.8.2 Measurement of earth resistances 348

6.5 Selection of materials 348

Acknowledgements 352

References 353

7 Internal lightning protection system 355

Peter Hasse and Peter Zahlmann

7.1 Damage due to lightning and other surges 355

7.1.1 Damage in hazardous areas 357

7.1.2 Lightning damage in city areas 357

7.1.3 Damage to airports 360

7.1.4 Consequences of lightning damage 361

7.2 Protective measures 361

7.2.1 Internal lightning protection 363

7.2.1.1 Equipotential bonding in accordance with IEC 60364-4-41 and -5-54 363

7.2.1.2 Equipotential bonding for a low-voltage system 364

7.2.1.3 Equipotential bonding for information technology system 364

7.2.2 Lightning protection zones concept 365

7.2.3 Basic protection measures: earthing magnetic shielding and bonding 366

7.2.3.1 Magnetic shielding 366

7.2.3.2 Cable shielding 369

7.2.3.3 Equipotential bonding network 371

7.2.3.4 Equipotential bonding on the boundaries of lightning protection zones 373

7.2.3.5 Equipotential bonding at the boundary of LPZ 0A and LPZ 2 380

7.2.3.6 Equipotential bonding on the boundary of LPZ 1 and LPZ 2 and higher 383

7.2.3.7 Coordination of the protective measures at various LPZ boundaries 385

7.2.3.8 Inspection and maintenance of LEMP protection 388

7.3 Surge protection for power systems: power supply systems (within the scope of the lightning protection zones concept according to IEC 62305-4) 389

7.3.1 Technical characteristics of SPDs 391

7.3.1.1 Maximum continuous voltage UC 391

7.3.1.2 Impulse current Iimp 392

7.3.1.3 Nominal discharge current In 392

7.3.1.4 Voltage protection level Up 392

7.3.1.5 Short-circuit withstand capability 392

7.3.1.6 Follow current extinguishing capability at UC (Ifi) 392

7.3.1.7 Follow current limitation (for spark-gap based SPDs class I) 393

7.3.1.8 Coordination 393

7.3.1.9 Temporary overvoltage 393

7.3.2 Use of SPDs in various systems 393

7.3.3 Use of SPDs in TN systems 396

7.3.4 Use of SPDs in TT systems 398

7.3.5 Use of SPDs in IT systems 401

7.3.6 Rating the lengths of connecting leads for SPDs 401

7.3.6.1 Series connection (V-shape) in accordance with IEC 60364-5-53 402

7.3.6.2 Parallel connection system in accordance with

IEC 60364-5-53 403

7.3.6.3 Design of the connecting lead on the earth side 405

7.3.6.4 Design of the phase-side connecting cables 406

7.3.7 Rating of cross-sectional areas and backup protection of SPDs410

7.3.7.1 Selectivity to the protection of the installation 416

7.4 Surge protection for telecommunication systems 417

7.4.1 Procedure for selection and installation of arresters:example BLITZDUCTOR CT 417

7.4.1.1 Technical data 418

7.4.2 Measuring and control systems 421

7.4.2.1 Electrical isolation using optocouplers 422

7.5 Examples for application 423

7.5.1 Lightning and surge protection of wind turbines 423

7.5.1.1 Positive prognoses 424

7.5.1.2 Danger resulting from lightning effects 424

7.5.1.3 Frequency of lightning strokes 424

7.5.1.4 Standardization 425

7.5.1.5 Protection measures 425

7.5.1.6 Shielding measures 426

7.5.1.7 Earth-termination system 426

7.5.2 Lightning and surge protection for photovoltaic systems and solar power plants 428

7.5.2.1 Lightning and surge protection for photovoltaic systems428

7.5.2.2 Lightning and surge protection for solar power plants 434

7.5.3 Surge protection for video surveillance systems 438

7.5.3.1 Video surveillance systems 439

7.5.3.2 Choice of SPDs 439

Bibliography 441

8 Risk analysis 443

Z. Flisowski and C. Mazzetti

8.1 General considerations 443

8.2 General concept of risk due to lightning 445

8.3 Number of strikes to a selected location 447

8.4 Damage probabilities 452

8.5 Simplified practical approach to damage probability457

8.6 Question of relative loss assessment 458

8.7 Concept of risk components 459

8.8 Standardized procedure of risk assessment 461

8.8.1 Basic relations 461

8.8.2 Evaluation of risk components 464

8.8.3 Risk reduction criteria 468

8.9 Meaning of subsequent strokes in a flash 470

8.10 Final remarks and conclusions 471

References 472

9 Low-frequency grounding resistance and lightning protection 475

Silverio Visacro

9.1 Introduction 475

9.2 Basic considerations about grounding systems 475

9.3 The concept of grounding resistance 476

9.4 Grounding resistance of some simple electrode arrangements 479

9.5 Relation of the grounding resistance to the experimental response of electrodes to lightning currents482

9.6 Typical arrangements of grounding electrodes for some relevant applications and their lightning-protection-related requirements487

9.6.1 Transmission lines 487

9.6.2 Substations 490

9.6.3 Lightning protection systems 494

9.6.4 Overhead distribution lines 496

9.7 Conclusion 497

References 499

10 High-frequency grounding 503

Leonid Grcev

10.1 Introduction 503

10.2 Basic circuit concepts 503

10.3 Basic field considerations 506

10.4 Frequency-dependent characteristics of the soil 509

10.5 Grounding modelling for high frequencies 511

10.6 Frequency-dependent grounding behaviour 514

10.7 Frequency-dependent dynamic grounding behaviour 521

10.8 Relation between frequency-dependent and non-linear

grounding behaviour 526

References 527

11 Soil ionization 531

Vernon Cooray

11.1 Introduction 531

11.2 Critical electric field necessary for ionization in soil 534

11.3 Various models used in describing soil ionization 536

11.3.1 Ionized region as a perfect conductor 536

11.3.2 Model of Liew and Darveniza 537

11.3.2.1 Application of the model to a single driven rod 538

11.3.3 Model of Wang and colleagues 540

11.3.4 Model of Sekioka and colleagues 543

11.3.5 Model of Cooray and colleagues 545

11.3.5.1 Mathematical description 546

11.3.5.2 Model parameters 548

11.4 Conclusions 550

References 550

12 Lightning protection of low-voltage networks 553

Alexandre Piantini

12.1 Introduction 553

12.2 Low-voltage networks 554

12.2.1 Typical configurations and earthing practices 554

12.2.2 Distribution transformers 558

12.2.3 Low-voltage power installations 564

12.3 Lightning surges on low-voltage systems 568

12.3.1 Direct strikes 568

12.3.2 Cloud discharges 570

12.3.3 Indirect strikes 571

12.3.3.1 Calculation of lightning-induced voltages 573

12.3.3.2 Sensitivity analysis 578

12.3.4 Transference from the medium-voltage line 601

12.3.4.1 Direct strikes 601

12.3.4.2 Indirect strikes 605

12.4 Lightning protection of LV networks 611

12.4.1 Distribution transformers 612

12.4.2 Low-voltage power installations 614

12.5 Concluding remarks 624

References

13 Lightning protection of medium voltage lines 635

C.A. Nucci and F. Rachidi

13.1 Introduction 635

13.2 Lightning strike incidence to distribution lines 636

13.2.1 Expected number of direct lightning strikes 638

13.2.2 Shielding by nearby objects 639

13.3 Typical overvoltages generated by direct and indirect lightning strikes 640

13.3.1 Direct overvoltages 640

13.3.2 Induced overvoltages 642

13.4 Main principles in lightning protection of distribution lines 645

13.4.1 Basic impulse insulation level and critical impulse flashover voltage 646

13.4.2 Shield wires 648

13.4.3 Protective devices 650

13.4.3.1 General considerations using protective devices 650

13.4.3.2 Spark gaps 651

13.4.3.3 Surge arresters 652

13.4.3.4 Capacitors 653

13.5 Lightning protection of distribution systems 653

13.5.1 Effect of the shield wire 653

13.5.2 Effect of surge arresters 655

13.5.3 Lightning performance of MV distribution lines 660

13.5.3.1 Effect of soil resistivity 662

13.5.3.2 Effect of the presence of shield wires 662

13.5.3.3 Effect of the presence of surge arresters 666

Appendix A13 Procedure to calculate the lightning

performance of

distribution lines according to IEEE Std. 1410-2004 (from Reference 4)666

Appendix B13 The LIOV-Monte Carlo (LIOV–MC) procedure to calculate the lightning performance of distribution lines (from Reference 56)668

Appendix C13 The LIOV code: models and equations 670

C13.1 Agrawal and colleagues field-to-transmission line coupling equations extended to the case of

multiconductor lines above a lossy earth 671

C13.2 Lightning-induced voltages on distribution networks: LIOV code interfaced

with EMTPrv 675

Acknowledgements 675

References 675

xvi Contents

14 Lightning protection of wind turbines 681

Troels Soerensen

14.1 Introduction 681

14.2 Nature of the lightning threat to wind turbines 686

14.3 Statistics of lightning damage to wind turbines 687

14.4 Risk assessment and cost–benefit evaluation 688

14.5 Lightning protection zoning concept 691

14.6 Earthing and equipotential bonding 693

14.7 Protection of wind turbine components 695

14.7.1 Blades 695

14.7.1.1 Blades with carbon fibre 699

14.7.1.2 Guidelines, quality assurance and test methods700

14.7.2 Hub 702

14.7.3 Nacelle 703

14.7.4 Tower 703

14.7.5 Bearings and gears 704

14.7.6 Hydraulic systems 705

14.7.7 Electrical systems, control and communication systems 706

14.7.7.1 Electrical systems 707

14.7.7.2 Generator circuit 707

14.7.7.3 Medium-voltage system 709

14.7.7.4 Auxiliary power circuit(s) 709

14.7.7.5 Control and communication systems 711

14.8 Wind farm considerations 713

14.9 Off-shore wind turbines 714

14.10 Lightning sensors and registration methods 716

14.11 Construction phase and personnel safety 717

References 718

15 Lightning protection of telecommunication towers 723

G.B. Lo Piparo

15.1 Lightning as a source of damage to broadcasting stations 723

15.1.1 General 723

15.1.2 Injury to people 725

15.1.3 Physical damage 725

15.1.3.1 Thermal effects 725

15.1.3.2 Electrodynamic effects 726

15.1.4 Failure of internal electrical and electronic systems 726

15.2 Effects of lightning flashes to the broadcasting station 726

15.2.1 Effects of lightning flashes to the antenna support structure 726

15.2.1.1 Lightning current flowing through external conductive parts and lines connected to the station 729

15.2.1.2 Potential differences between different parts of the earth-termination system of the station 730

15.3 Lightning flashes affecting the power supply system 731

15.3.1 Power supply by overhead lines 731

15.3.1.1 Lightning flashes to an overhead line 731

15.3.1.2 Lightning flash to ground near an overhead line733

15.3.1.3 Surges at the point of entry of an overhead line in the station 733

15.3.1.4 Overhead line connected directly to the transformer 734

15.3.1.5 Buried cable connection between the overhead line and the transformer734

15.3.2 Power supply by underground cable 735

15.3.3 Transfer of overvoltages across the transformer735

15.4 The basic principles of lightning protection 736

15.4.1 The protection level to be provided 736

15.4.2 Basic criteria for protection of stations 737

15.4.3 Protection measures 738

15.4.4 Procedure for selection of protection measures739

15.4.5 Implementation of protection measures 739

15.5 Erection of protection measures to reduce injury of living beings 742

15.5.1 Protection measures against step voltages 742

15.5.2 Protection measures against touch-voltages 742

15.6 Erection of the LPS to reduce physical damage 743

15.6.1 Air-termination system 743

15.6.2 Down-conductors system 743

15.6.3 Earth-termination system 745

15.6.3.1 Earth-termination system for stations with an autonomous power supply 747

15.6.3.2 Earth-termination system for stations powered by an external source 749

15.6.4 Protection against corrosion 753

15.6.5 Earthing improvement 753

15.6.6 Foundation earth electrode 754

15.7 Potential equalization to reduce failures of electrical and electronic systems757

15.7.1 Potential equalization for the earth-termination system of the station 757

15.7.2 Potential equalization for the antenna support structure 761

15.7.3 Potential equalization for the equipment within the building 761

15.7.4 Potential equalization for metallic objects outside the building 763

15.8 Screening to reduce failures of electrical and electronic systems 763

15.8.1 Screening of circuits within the building 763

15.8.2 Circuits of the station entering the building 764

15.9 Coordinated SPD protection system to reduce failures of electrical and electronic systems 766

15.9.1 Selection of SPDs with regard to voltage protection level 766

15.9.2 Selection of SPD with regard to location and to discharge current766

15.9.3 Installation of SPDs in a coordinated SPD protection system 767

15.9.3.1 Protective distance lP 767

15.9.3.2 Induction protective distance lPi 768

15.10 Protection of lines and services entering the station 768

15.10.1 Overhead lines 769

15.10.2 Screened cables 770

15.11 Arrangement of power supply circuits 771

15.11.1 Stations supplied at high voltage 771

15.11.2 Stations supplied at low voltage 773

15.11.3 Stations with self-contained power supplies only 776

Annex A15: Surge testing of installations 776

A15.1 Simulation of surge phenomena 776

A15.1.1 General 776

A15.1.2 Tests for determining overvoltages due to lightning flashes to the antenna-support structure 777

A15.1.3 Determination of the transferred overvoltages 777

A15.1.4 Results 778

A15.2 Description of a typical test programme 779

A15.2.1 Introduction 779

A15.2.2 The power supply arrangements of the station 780

A15.2.3 The test equipment 781

A15.2.4 The test procedure and results 781

A15.2.4.1 Measurement of the overvoltages due to

lightning flashes to the antenna-support structure 783

A15.2.4.2 Measurement of the transferred overvoltages783

A15.3 Discussion of the results 784

A15.3.1 Lightning flashes to the antenna-supportstructure 786

A15.3.2 Overvoltages transferred by the power supply line 786

A15.4 Conclusions 787

Acknowledgements 787

References 787

16 Lightning protection of satellite launch pads 789

Udaya Kumar

16.1 Introduction 789

16.2 Structure of a rocket 790

16.3 Launch pad 791

16.3.1 Launch campaign and duration of exposure 792

16.4 Lightning threat to launch vehicle 792

16.4.1 Limitations of present-day knowledge in quantifying the risk793

16.5 Lightning protection systems 794

16.5.1 External protection 794

16.5.1.1 Brief description of some of the present protection schemes 796

16.5.2 Principles used for the design of the external protection system 798

16.5.2.1 Air termination network 798

16.5.2.2 Earth termination 799

16.5.2.3 Down-conductor system 799

16.5.3 Internal protection 799

16.5.3.1 Launch vehicle 799

16.5.3.2 Vehicle on launch pad 801

16.6 Weather launch commit criteria 802

16.7 Review of present status and suggested direction for further work 803

16.7.1 Attachment process 803

16.7.2 Lightning surge response 806

16.7.2.1 Earth termination 806

16.7.2.2 Down-conductor system 807

16.7.3 Weather launch commit criteria 813

16.8 Indirect effects 813

16.9 Protection of other supporting systems 814

16.10 On-site measurements 814

16.11 Summary 815

References 816

17 Lightning protection of structures with risk of fire and explosion 821 Arturo Galva´n Diego

17.1 Introduction 821

17.2 Tanks and vessels containing flammable materials 822

17.2.1 General 822

17.2.2 Risk assessment 824

17.2.3 Lightning protection measures 825

17.2.3.1 Air terminations 826

17.2.3.2 Equipotential bonding 828

17.2.3.3 A clean environment 829

17.2.3.4 Self-protecting system 829

17.2.3.5 Resume´ for lightning protection 830

17.3 Offshore oil platforms 830

17.3.1 General 830

17.3.2 Relevant standards 831

17.3.3 Risk assessment 832

17.3.4 Lightning protection measures 832

17.3.4.1 External lightning protection 832

17.3.4.2 Grounding system and common bonding network 834

17.3.4.3 Internal grounding system 835

17.3.4.4 Shielding 838

17.3.4.5 Location of SPD 839

References 839

18 Lightning and trees 843

Mahendra Fernando, Jakke Ma¨kela¨ and Vernon Cooray

18.1 Introduction 843

18.2 Strike and damage probability of lightning to trees

844

18.3 Types of lightning damage 846

18.3.1 Microscale damage 846

18.3.2 Macroscale damage 847

18.3.2.1 No physical damage 847

18.3.2.2 Bark-loss damage 849

18.3.2.3 Wood-loss damage 849

18.3.2.4 Explosive damage 849

18.3.2.5 Ignition 850

18.3.3 Other damage scenarios 852

18.3.3.1 Long-term propagation of damage 853

18.3.3.2 Group damage to trees 853

18.3.3.3 Damage to ground 853

18.3.3.4 Damage to vegetation 854

18.4 Protection of trees 854

18.5 Conclusions 855

Acknowledgements 855

References 855

19 Lightning warning systems 859

Martin J. Murphy, Kenneth L. Cummins and Ronald L. Holle

19.1 Introduction 859

19.2 Thunderstorm lifecycle and associated detection methods 860

19.2.1 Thunderstorm life cycle 860

19.2.1.1 Convective development and electrification 860

19.2.1.2 Early stages of lightning activity 861

19.2.1.3 Late stages of lightning activity 861

19.2.2 Associated detection methods 862

19.2.2.1 Detection of initial electrification 862

19.2.2.2 Single-point lightning detection sensors 863

19.2.2.3 Lightning detection networks 864

19.3 Examples of warning systems 864

19.3.1 Fixed-point warning applications 864

19.3.2 Storm-following algorithms 867

19.4 Warning system performance measures 869

19.4.1 Performance metrics 869

19.4.1.1 Performance metrics for fixed-point algorithms 870

19.4.1.2 Performance metrics for storm-following algorithms 873

19.4.2 Specific challenges at different stages of the warning problem 875

19.4.2.1 Lightning onset 875

19.4.2.2 Lightning cessation 876

19.5 Application of performance measures to cloud-to-ground warning systems879

19.5.1 Assessment of a fixed-point warning algorithm 879

19.5.1.1 Effects of lightning detection technology 879

19.5.1.2 Effects of algorithm configuration using a single detection technology 884

19.5.2 Lightning cessation in MCS cases 884

19.5.3 Radar applications for lightning onset in storm-following algorithms885

19.6 Assessing the risks 887

19.6.1 Decision making 887

19.6.2 Equipment protection application 891

9.6.3 Trade-offs between performance and risks for cloud-to-ground warning in safety applications 892

19.6.3.1 Personal and small-group warning 892

19.6.3.2 Large venue warning 893

References 894

20 Lightning-caused injuries in humans 901

Vernon Cooray, Charith Cooray and Christopher Andrews

20.1 Introduction 901

20.2 The different ways in which lightning can interact with humans 902

20.3 Different types of injuries 906

20.3.1 Injuries to the respiratory and cardiovascular system 906

20.3.2 Injuries to the eye 909

20.3.3 Ear 910

20.3.4 Nervous system 912

20.3.5 Skin and burn injuries 913

20.3.6 Psychological 914

20.3.7 Blunt injuries 914

20.3.8 Disability caused by lightning 915

20.3.9 Remote injuries 915

20.3.10 Lightning electromagnetic fields 917

20.4 Concluding remarks 920

References 920

21 Lightning standards 925

Fridolin Heidler and E.U. Landers

21.1 Introduction 925

21.2 Standardized lightning currents 926

21.2.1 Threat parameters of the lightning current 926

21.2.2 Current waveforms 928

21.2.3 Requirements for the current tests 930

21.3 Determination of possible striking points 931

21.3.1 Rolling sphere method 931

21.3.2 Mesh method 933

21.3.3 Protection angle method 933

21.4 The lightning protection system (LPS) 934

21.4.1 Air termination system 934

21.4.2 Down-conductor system 935

21.4.3 Earth termination system 935

21.4.4 Lightning equipotential bonding 937

21.4.5 Separation distance 938

21.5 The LEMP protection measures system (LPMS) 939

21.5.1 The lightning protection zones (LPZ) concept 939

21.5.2 Earthing system and bonding network 941

21.5.3 Line routing and shielding 942

21.5.4 Coordinated surge protection device application 942

21.5.5 Spatial magnetic shielding 942

21.6 Conclusions 944

References 946

22 High-voltage and high-current testing 947

Wolfgang Zischank

22.1 Introduction 947

22.2 Lightning test equipment 948

22.2.1 High-voltage impulse test generators 948

22.2.1.1 Single-stage impulse voltage circuits 950

22.2.1.2 Multistage impulse voltage circuits 953

22.2.2 High-current test generators 956

22.2.2.1 Simulation of first return stroke effects 957

22.2.2.2 Simulation of subsequent return stroke effects 967

22.2.2.3 Generation of long-duration currents 970

22.2.2.4 Current injection for direct effects testing 971

22.2.3 Indirect effects testing 972

22.3 Measurement techniques 974

22.3.1 Measurement of impulse voltages 974

22.3.2 Measurement of impulse currents 975

22.3.2.1 Resistive shunts 975

22.3.2.2 Rogowski coils 976

22.3.2.3 Current monitors 977

References 978

23 Return stroke models for engineering applications 981

Vernon Cooray

23.1 Introduction 981

23.2 Current propagation models (CP models) 983

23.2.1 Basic concept 983

23.2.2 Most general description 984

23.3 Current generation models (CG models) 986

23.3.1 Basic concept 986

23.3.2 Mathematical background 988

23.3.2.1 Evaluate Ib(t) given r(z), t(z) and v(z) 988

23.3.2.2 Evaluate t(z) given Ib(t), r(z) and v(z) 989

23.3.2.3 Evaluate r(z) given Ib(t), t(z) and v(z) 990

23.3.2.4 Evaluate v(z), given Ib(t), r(z) and t(z) 990

23.3.3 CG models in practice 990

23.3.3.1 Model of Wagner 991

23.3.3.2 Model of Heidler 991

23.3.3.3 Model of Hubert 992

23.3.3.4 Model of Cooray 993

23.3.3.5 Model of Diendofer and Uman 994

23.3.3.6 First modification of the Diendofer and Uman model by Thottappillil et al.996

23.3.3.7 Second modification of the Diendofer and Uman model by Thottappillil and Uman997

23.3.3.8 Model of Cooray 998

23.3.3.9 Model of Cooray and Rakov 999

23.3.3.10 Model of Cooray, Rakov and Montano 1000

23.4 Current dissipation models (CD Models) 1001

23.4.1 General description 1001

23.4.2 Mathematical background 1003

23.4.3 Cooray and Rakov model – a combination of current dissipation and current generation models 1004

23.5 Generalization of any model to the current generation type 1006

23.6 Generalization of any model to the current dissipation type 1008

23.7 Current dissipation models and the modified transmission line models 1009

23.8 Effect of ground conductivity 1010

23.9 Equations necessary to calculate the electric and magnetic fields 1012

23.10 Concluding remarks 1015

References 1016

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Electronic Circuits,Fundamental and Applications

Content :
1. Electrical fundamentals
2. Passive components
3. D.C. circuits
4. Alternating voltage and current
5. Semiconductore
6. Power Supplies
7. Amplifiers
8. Operational amplifiers
9. Oscilators
10. Logic circuits

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Electrical Engineering Problem & Solution

136 pages 5.5 Mb

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Electrical Circuit Theory and Technology

994 pages 5.2 Mb

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Technologies for Electrical Power Conversion Efficiency and Distribution

Section 1 Energy, Conversion and  Storage of Energy

Chapter 1 Energy and Energy Efficiency
Energy Sources 1
Energy Efficiency and Contemporary Trends 6
References 9

Chapter 2 Storage and Usage of Energy 10
Overview 10
Storage of Energy as Electrochemical Energy 11
Storage of Energy as Electromagnetic Energy 21
Storage of Energy as Electrostatic Energy 24
Storage of Energy as Mechanical Energy 26
Using the Energy as Electrical Energy 30
References 30

Chapter 3 Power Electronics and Its Role in Effective Conversion of Electrical Energy
Overview 32
Principles of Conversion of Electrical Energy 36
Computer-Aided Design of Power Electronic Converters in Power Electronics  41
References 47
End notes 58

Section 2 Electronic Energy Converters
Chapter 4 AC/DC Conversion 50
Basic Indicators in Respect to the Supply Network 50
Single-Phase and Three-Phase Uncontrolled Rectifiers 55
Single-Phase and Three-Phase Controlled Rectifiers 66
Bidirectional AC/DC Conversion 77
Methods to Improve Power Efficiency in AC/DC Conversion 83
References 96

Chapter 5 AC/AC Conversion 98
Basic Indicators in Respect to the Supply Network 98
Single-Phase and Three-Phase AC Regulators 199
Methods to Improve Power Efficiency in AC/AC Conversion 114
References 133

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energy-efficient_electric_motor_selection_handbook

Efficient use of energy enables commercial and industrial facilities to minimize production costs, increase profits, and stay competitive. The majority of electrical energy consumed in most industrial facilities is used to run electric motors. Energy-efficient motors now available are typically from 2 to 6 percent more ef-ficient than their standard motor counterparts. This efficiency improvement translates into substantial energy and dollar savings. For instance, a recent study of Northwest industrial sector energy conservation measures revealed a potential for 52.7 MWa of energy savings by replacing standard motors with high-efficiency motors. This savings is annually valued at $13.8 million given an electricity price of only $0.03/kWh (see Chapter 5).


The price premium for an energy-efficient motor is typically 15 to 30 percent above the cost of a standard motor. Over a typical lo-year operating life, a motor can easily consume electricity valued at over 57 times its initial purchase price. This means that when you spend $1,600 to purchase a motor, you are obligating yourself to purchase over $92,000 worth of electrical energy to operate it. A price premium of $400 is negligible compared to saving 3 percent of $92,000 or $2,760. Purchasing new or replacement energy-efficient motors makes good economic sense (see Chapter 5).


Energy-efficient motors are truly premium motors. The efficiency gains are obtained through the use of refined design, better materials, and improved construction. Many motor manufacturers offer an extended warranty for their premium-efficiency motor lines. Yet only 15 percent of motor sales nationwide are of high-efficiency units. Because of our low-cost electricity, this percentage is undoubtedly even lower in the Northwest region.


Durable and reliable energy-efficient motors can be extremely cost effective with simple paybacks on investment of less than 2 years-even in the Northwest. Energy efficient motors should be considered in the following instances. • For new facilities or when modifications are made to existing installations or processes • When procuring equipment packages • Instead of rewinding failed motors • To replace oversized and underloaded motors • As part of an energy management or preventative maintenance program • When utility rebates am offered that make high-efficiency motor retrofits even more cost effective

This Energy-Efficient Electric Motor Selection Handbook (Handbook) shows you how to assess energy savings and cost effectiveness when making motor purchase decisions.

The Handbook also discusses high-efficiency motor speed characteristics, performance under part-load conditions, and operation with an abnormal power supply.Additionally, the Handbook tells you where further information is available. For example, you can obtain performance and price data for both standard and energy efficient motors from the Electric Ideas Clearinghouse 1-800-872-3568, or 206-586-8588 outside of BPA’s service area. Finally, the Handbook contains a motor test data
sheet (Appendix A) and a list of Northwest motor manufacturers’ representatives (Appendix B).

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The Complete Idiot's Guide To Electrical Repair

Total 432 pages 6 mb

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High Voltage Engineering Fundamentals

Contents
Preface to second edition xi
Preface to first edition xv
Chapter 1 Introduction 1
1.1 Generation and transmission of electric energy 1
1.2 Voltage stresses 3
1.3 Testing voltages 5
1.3.1 Testing with power frequency voltages 5
1.3.2 Testing with lightning impulse voltages 5
1.3.3 Testing with switching impulses 6
1.3.4 D.C. voltages 6
1.3.5 Testing with very low frequency voltage 7
References 7

Chapter 2 Generation of high voltages 8
2.1 Direct voltages 9
2.1.1 A.C. to D.C. conversion 10
2.1.2 Electrostatic generators 24
2.2 Alternating voltages 29
2.2.1 Testing transformers 32
2.2.2 Series resonant circuits 40
2.3 Impulse voltages 48
2.3.1 Impulse voltage generator circuits 52
2.3.2 Operation, design and construction of impulse generators 66
2.4 Control systems 74
References 75

Chapter 3 Measurement of high voltages 77
3.1 Peak voltage measurements by spark gaps 78
3.1.1 Sphere gaps 79
3.1.2 Reference measuring systems 91
3.1.3 Uniform field gaps 92
3.1.4 Rod gaps 93
3.2 Electrostatic voltmeters 94
3.3 Ammeter in series with high ohmic resistors and high ohmic resistor voltage dividers 96
3.4 Generating voltmeters and field sensors 107
3.5 The measurement of peak voltages 109
3.5.1 The Chubb–Fortescue method 110
3.5.2 Voltage dividers and passive rectifier circuits 113
3.5.3 Active peak-reading circuits 117
3.5.4 High-voltage capacitors for measuring circuits 118
3.6 Voltage dividing systems and impulse voltage measurements 129
3.6.1 Generalized voltage generation and measuring circuit 129
3.6.2 Demands upon transfer characteristics of the measuring system 132
3.6.3 Fundamentals for the computation of the measuring system 139
3.6.4 Voltage dividers 147
3.6.5 Interaction between voltage divider and its lead 163
3.6.6 The divider’s low-voltage arm 171
3.7 Fast digital transient recorders for impulse measurements 175
3.7.1 Principles and historical development of transient digital recorders176
3.7.2 Errors inherent in digital recorders 179
3.7.3 Specification of ideal A/D recorder and parameters required for h.v.impulse testing 183
3.7.4 Future trends 195
References 196

Chapter 4 Electrostatic fields and field stress control 201
4.1 Electrical field distribution and breakdown strength of insulating materials 201
4.2 Fields in homogeneous, isotropic materials 205
4.2.1 The uniform field electrode arrangement 206
4.2.2 Coaxial cylindrical and spherical fields 209
4.2.3 Sphere-to-sphere or sphere-to-plane 214
4.2.4 Two cylindrical conductors in parallel 218
4.2.5 Field distortions by conducting particles 221
4.3 Fields in multidielectric, isotropic materials 225
4.3.1 Simple configurations 227
4.3.2 Dielectric refraction 232
4.3.3 Stress control by floating screens 235
4.4 Numerical methods 241
4.4.1 Finite difference method (FDM) 242
4.4.2 Finite element method (FEM) 246
4.4.3 Charge simulation method (CSM) 254
4.4.4 Boundary element method 270
References 278

Chapter 5 Electrical breakdown in gases 281
5.1 Classical gas laws 281
5.1.1 Velocity distribution of a swarm of molecules 284
5.1.2 The free path of molecules and electrons 287
5.1.3 Distribution of free paths 290
5.1.4 Collision-energy transfer 291
5.2 Ionization and decay processes 294
5.2.1 Townsend first ionization coefficient 295
5.2.2 Photoionization 301
5.2.3 Ionization by interaction of metastables with atoms 301
5.2.4 Thermal ionization 302
5.2.5 Deionization by recombination 302
5.2.6 Deionization by attachment–negative ion formation 304
5.2.7 Mobility of gaseous ions and deionization by diffusion 308
5.2.8 Relation between diffusion and mobility 314
5.3 Cathode processes – secondary effects 316
5.3.1 Photoelectric emission 317
5.3.2 Electron emission by positive ion and excited atom impact 317
5.3.3 Thermionic emission 318
5.3.4 Field emission 319
5.3.5 Townsend second ionization coefficient 321
5.3.6 Secondary electron emission by photon impact 323
5.4 Transition from non-self-sustained discharges to breakdown 324
5.4.1 The Townsend mechanism 324
5.5 The streamer or ‘Kanal’ mechanism of spark 326
5.6 The sparking voltage–Paschen’s law 333
5.7 Penning effect 339
5.8 The breakdown field strength (Eb) 340
5.9 Breakdown in non-uniform fields 342
5.10 Effect of electron attachment on the breakdown criteria 345
5.11 Partial breakdown, corona discharges 348
5.11.1 Positive or anode coronas 349
5.11.2 Negative or cathode corona 352
5.12 Polarity effect – influence of space charge 354
5.13 Surge breakdown voltage–time lag 359
5.13.1 Breakdown under impulse voltages 360
5.13.2 Volt–time characteristics 361
5.13.3 Experimental studies of time lags 362
References 365

Chapter 6 Breakdown in solid and liquid dielectrics 367
6.1 Breakdown in solids 367
6.1.1 Intrinsic breakdown 368
6.1.2 Streamer breakdown 373
6.1.3 Electromechanical breakdown 373
6.1.4 Edge breakdown and treeing 374
6.1.5 Thermal breakdown 375
6.1.6 Erosion breakdown 381
6.1.7 Tracking 385
6.2 Breakdown in liquids 385
6.2.1 Electronic breakdown 386
6.2.2 Suspended solid particle mechanism 387
6.2.3 Cavity breakdown 390
6.2.4 Electroconvection and electrohydrodynamic model of dielectric breakdown 391
6.3 Static electrification in power transformers 393
References 394

Chapter 7 Non-destructive insulation test techniques 395
7.1 Dynamic properties of dielectrics 395
7.1.1 Dynamic properties in the time domain 398
7.1.2 Dynamic properties in the frequency domain 404
7.1.3 Modelling of dielectric properties 407
7.1.4 Applications to insulation ageing 409
7.2 Dielectric loss and capacitance measurements 411
7.2.1 The Schering bridge 412
7.2.2 Current comparator bridges 417
7.2.3 Loss measurement on complete equipment 420
7.2.4 Null detectors 421
7.3 Partial-discharge measurements 421
7.3.1 The basic PD test circuit 423
7.3.2 PD currents 427
7.3.3 PD measuring systems within the PD test circuit 429
7.3.4 Measuring systems for apparent charge 433
7.3.5 Sources and reduction of disturbances 448
7.3.6 Other PD quantities 450
7.3.7 Calibration of PD detectors in a complete test circuit 452
Contents ix
7.3.8 Digital PD instruments and measurements 453

Chapter 8 Overvoltages, testing procedures and insulation coordination 460
8.1 The lightning mechanism 460
8.1.1 Energy in lightning 464
8.1.2 Nature of danger 465
8.2 Simulated lightning surges for testing 466
8.3 Switching surge test voltage characteristics 468
8.4 Laboratory high-voltage testing procedures and statistical treatment of results472
8.4.1 Dielectric stress–voltage stress 472
8.4.2 Insulation characteristics 473
8.4.3 Randomness of the appearance of discharge 473
8.4.4 Types of insulation 473
8.4.5 Types of stress used in high-voltage testing 473
8.4.6 Errors and confidence in results 479
8.4.7 Laboratory test procedures 479
8.4.8 Standard test procedures 484
8.4.9 Testing with power frequency voltage 484
8.4.10 Distribution of measured breakdown probabilities (confidence in measured P V ) 485
8.4.11 Confidence intervals in breakdown probability (in measured values)487
8.5 Weighting of the measured breakdown probabilities 489
8.5.1 Fitting of the best fit normal distribution 489
8.6 Insulation coordination 492
8.6.1 Insulation level 492
8.6.2 Statistical approach to insulation coordination 495
8.6.3 Correlation between insulation and protection levels 498
8.7 Modern power systems protection devices 500
8.7.1 MOA – metal oxide arresters 500
References 507

Chapter 9 Design and testing of external insulation 509
9.1 Operation in a contaminated environment 509
9.2 Flashover mechanism of polluted insulators under a.c. and d.c. 510
9.2.1 Model for flashover of polluted insulators 511
9.3 Measurements and tests 512
9.3.1 Measurement of insulator dimensions 513
9.3.2 Measurement of pollution severity 514
9.3.3 Contamination testing 517
9.3.4 Contamination procedure for clean fog testing 518
9.3.5 Clean fog test procedure 519
9.3.6 Fog characteristics 520
9.4 Mitigation of contamination flashover 520
9.4.1 Use of insulators with optimized shapes 520
9.4.2 Periodic cleaning 520
9.4.3 Grease coating 521
9.4.4 RTV coating 521
9.4.5 Resistive glaze insulators 521
9.4.6 Use of non-ceramic insulators 522
9.5 Design of insulators 522
9.5.1 Ceramic insulators 523
9.5.2 Polymeric insulators (NCI) 526
9.6 Testing and specifications 530
9.6.1 In-service inspection and failure modes 531
References 531
Index 533


Total 552 pages 5 mb
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Electronic & Electrical servicing

Contents
Unit 1 D.c. technology, components and circuits 1
1 Direct current technology 3
2 Conductors, insulators, semiconductors and wiring 21
3 Resistors and resistive circuits 30

Unit 2 A.c. technology and electronic components 45
4 Magnetism 47
5 Capacitance and capacitors 60
6 Waveforms 70

Unit 3 Electronic devices and testing 79
7 Semiconductor diodes 81
8 Transistors 93

Unit 4 Electronic systems 105
9 Other waveforms 107
10 Transducers and sensors 116
11 Transducers (2) 125
12 Electronic modules 133

Unit 5 Digital electronics 149
13 Logic systems 151
14 Digital oscillators, timers and dividers 163
15 Digital inputs and outputs 171

Unit 6 Radio and television systems technology 179
16 Home entertainment systems 181
17 Frequency modulation 198
18 Television systems 206
19 Television receivers 219

Unit 7 PC technology 231
20 The personal computer 233
21 Installing a PC 248
22 Keyboard, mouse and monitors 257
23 Drives 269
24 Printers 281
25 Health and safety 293

Total 333 Pages 2 mb
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