Electrical EngineeringChapter 2 Fundamentals of Electric Circuits 13 2.1 Introduction 13 2.2 Charge and Current 15 2.3 Voltage 17 2.4 Respective Direction of Voltage and Current 18

Electrical EngineeringConcepts and Applications

©2013 Pearson Education, Inc., Upper Saddle River, NJ 07458. All Rights Reserved


Electrical Engineering Concepts and Applications

S. A. Reza Zekavat

Michigan Technological University

Upper Saddle River Boston Columbus San Franciso New York

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Library of Congress Cataloging-in-Publication Data

Zekavat, Seyed A.

Electrical engineering: concepts and applications / Seyed A. (Reza) Zekavat.—1st ed.

p. cm.

ISBN-13: 978-0-13-253918-0

ISBN-10: 0-13-253918-7

1. Electrical engineering—Textbooks. I. Title.

TK165.Z45 2012

621.3—dc23

2011029582

10 9 8 7 6 5 4 3 2 1

ISBN 10: 0-13-253918-7

ISBN 13: 978-0-13-253918-0©2013 Pearson Education, Inc., Upper Saddle River, NJ 07458. All Rights Reserved

Dedication

To my father, Seyed Hassan, and mother Azardokht



vii

CONTENTS

Preface xvii Acknowledgements xix

Chapter 1 Why Electrical Engineering? 1

1.1 Introduction 1

1.2 Electrical Engineering and a Successful Career 2

1.3 What Do You Need to Know about EE? 2

1.4 Real Career Success Stories 3

1.5 Typical Situations Encountered on the Job 4

1.5.1 On‐the‐Job Situation 1: Active Structural Control 4

1.5.2 On‐the‐Job Situation 2: Chemical Process Control 6

1.5.3 On‐the‐Job Situation 3: Performance of an Off‐Road Vehicle Prototype 8

Further Reading 12

Chapter 2 Fundamentals of Electric Circuits 13

2.1 Introduction 13

2.2 Charge and Current 15

2.3 Voltage 17

2.4 Respective Direction of Voltage and Current 18

2.5 Kirchhoff’s Current Law 18

2.6 Kirchhoff’s Voltage Law 22

2.7 Ohm’s Law and Resistors 27

2.7.1 Resistivity of a Resistor 29

2.7.2 Nonlinear Resistors 32

2.7.3 Time‐Varying Resistors 32

2.8 Power and Energy 32

2.8.1 Resistor‐Consumed Power 36

2.9 Independent and Dependent Sources 38

2.10 Analysis of Circuits Using PSpice 42

Bias Point Analysis 45

Time Domain (Transient) Analysis 46

Copy the Simulation Plot to the Clipboard to Submit Electronically 47

2.11 What Did You Learn? 53

Problems 54

Chapter 3 Resistive Circuits 61

3.1 Introduction 61

3.2 Resistors in Parallel and Series and Equivalent Resistance 62

3.3 Voltage and Current Division/Divider Rules 71

3.3.1 Voltage Division 71

3.3.2 Current Division 74 ©2013 Pearson Education, Inc., Upper Saddle River, NJ 07458. All Rights Reserved

viii Contents

3.4 Nodal and Mesh Analysis 81

3.4.1 Nodal Analysis 81

3.4.2 Mesh Analysis 88

3.5 Special Conditions: Super Node 92

3.6 Thévenin/Norton Equivalent Circuits 99

3.6.1 Source Transformation 108

3.7 Superposition Principle 112

3.8 Maximum Power Transfer 118

3.9 Analysis of Circuits Using PSpice 122


Problems 126

Chapter 4 Capacitance and Inductance 135

4.1 Introduction 135

4.2 Capacitors 136

4.2.1 The Relationship Between Charge, Voltage, and Current 138

4.2.2 Power 140

4.2.3 Energy 140

4.3 Capacitors in Series and Parallel 141

4.3.1 Series Capacitors 141

4.3.2 Parallel Capacitance 142

4.4 Inductors 147

4.4.1 The Relationship Between Voltage and Current 147

4.4.2 Power and Stored Energy 148

4.5 Inductors in Series and Parallel 149

4.5.1 Inductors in Series 150

4.5.2 Inductors in Parallel 150

4.6 Applications of Capacitors and Inductors 152

4.6.1 Fuel Sensors 152

4.6.2 Vibration Sensors 153

4.7 Analysis of Capacitive and Inductive Circuits Using PSpice 156


Problems 159

Chapter 5 Transient Analysis 164


5.2 First‐Order Circuits 165

5.2.1 RC Circuits 165

5.2.2 RL Circuits 179

5.3 DC Steady State 186

5.4 DC Steady State for Capacitive–Inductive Circuits 188

5.5 Second‐Order Circuits 189


Contents ix

5.5.1 Series RLC Circuits with a DC Voltage Source 189

5.5.2 Parallel RLC Circuits with a DC Voltage Source 196

5.6 Transient Analysis with Sinusoid Forcing Functions 198

5.7 Using PSpice to Investigate the Transient Behavior of RL and RC Circuits 201


Problems 208

Chapter 6 Steady‐State AC Analysis 215

6.1 Introduction: Sinusoidal Voltages and Currents 215

6.1.1 Root‐Mean‐Square (rms) Values (Effective Values) 220

6.1.2 Instantaneous and Average Power 221

6.2 Phasors 222

6.2.1 Phasors in Additive or (Subtractive) Sinusoids 224

6.3 Complex Impedances 225

6.3.1 The Impedance of a Resistor 225

6.3.2 The Impedance of an Inductor 225

6.3.3 The Impedance of a Capacitor 226

6.3.4 Series Connection of Impedances 228

6.3.5 Parallel Connection of Impedances 229

6.4 Steady‐State Circuit Analysis Using Phasors 231

6.5 Thévenin and Norton Equivalent Circuits with Phasors 239

6.5.1 Thévenin Equivalent Circuits with Phasors 239

6.5.2 Norton Equivalent Circuits with Phasors 240

6.6 AC Steady‐State Power 243

6.6.1 Average Power 245

6.6.2 Power Factor 246

6.6.3 Reactive Power 246

6.6.4 Complex Power 247

6.6.5 Apparent Power 249

6.6.6 Maximum Average Power Transfer 252

6.6.7 Power Factor Correction 254

6.7 Steady‐State Circuit Analysis Using PSpice 259


Problems 267

Chapter 7 Frequency Analysis 274


7.2 First‐Order Filters 275

7.2.1 Transfer Functions 275

7.3 Low‐Pass Filters 276

7.3.1 Magnitude and Phase Plots 280

7.3.2 Decibels 280

7.3.3 Bode Plot 282


x Contents

7.4 High‐Pass Filters 285

7.4.1 Cascaded Networks 287

7.5 Second‐Order Filters 289

7.5.1 Band‐Pass Filters 289

7.5.2 Band‐Stop Filters 291

7.6 MATLAB Applications 293

7.7 Frequency Response Analysis Using PSpice 300


Problems 310

Chapter 8 Electronic Circuits 316


8.2 P‐Type and N‐Type Semiconductors 317

8.3 Diodes 319

8.3.1 Diode Applications 323

8.3.2 Different Types of Diodes 329

8.3.3 AC‐to‐DC Converter 335

8.4 Transistors 338

8.4.1 Bipolar Junction Transistor 338

8.4.2 Transistor as an Amplifier 339

8.4.3 Transistors as Switches 356

8.4.4 Field‐Effect Transistors 357

8.4.5 Design of NOT Gates Using NMOS Only for High‐Density Integration 367

8.4.6 Design of a Logic Gate Using CMOS 369

8.5 Operational Amplifiers 371

8.6 Using PSpice to Study Diodes and Transistors 377


Further Reading 385

Problems 386

Chapter 9 Power Systems and Transmission Lines 395


9.2 Three‐Phase Systems 396

9.2.1 Introduction 396

9.2.2 Phase Sequence 398

9.2.3 Y‐Connected Generators 398

9.2.4 Y‐Connected Loads 398

9.2.5 ∆‐Connected Loads 401

9.2.6 ∆‐Star and Star‐∆ Transformations 404

9.2.7 Power in Three‐Phase Systems 406

9.2.8 Comparison of Star and ∆ Load Connections 411

9.2.9 Advantages of Three‐Phase Systems 411 ©2013 Pearson Education, Inc., Upper Saddle River, NJ 07458. All Rights Reserved

Contents xi

9.3 Transmission Lines 412

9.3.1 Introduction 412

9.3.2 Resistance (R) 414

9.3.3 Different Types of Conductors 415

9.3.4 Inductance (L) 416

9.3.5 Capacitance 421

9.3.6 Transmission Line Equivalent Circuits 424

9.4 Using PSpice to Study Three‐Phase Systems 432


Further Reading 435

Problems 436

Chapter 10 Fundamentals of Logic Circuits 440


10.2 Number Systems 442

10.2.1 Binary Numbers 442

10.2.2 Hexadecimal Numbers 449

10.2.3 Octal Numbers 450

10.3 Boolean Algebra 451

10.3.1 Boolean Inversion 451

10.3.2 Boolean AND Operation 451

10.3.3 Boolean OR Operation 452

10.3.4 Boolean NAND Operation 452

10.3.5 Boolean NOR Operation 452

10.3.6 Boolean XOR Operation 452

10.3.7 Summary of Boolean Operations 452

10.3.8 Rules Used in Boolean Algebra 452

10.3.9 De Morgan’s Theorems 453

10.3.10 Commutativity Rule 454

10.3.11 Associativity Rule 454

10.3.12 Distributivity Rule 454

10.4 Basic Logic Gates 459

10.4.1 The NOT Gate 459

10.4.2 The AND Gate 459

10.4.3 The OR Gate 460

10.4.4 The NAND Gate 460

10.4.5 The NOR Gate 460

10.4.6 The XOR Gate 463

10.4.7 The XNOR Gate 463

10.5 Sequential Logic Circuits 466

10.5.1 Flip‐Flops 466

10.5.2 Counter 470


xii Contents

10.6 Using PSpice to Analyze Digital Logic Circuits 474


Reference 482

Problems 483

Chapter 11 Computer‐Based Instrumentation Systems 488


11.2 Sensors 489

11.2.1 Pressure Sensors 490

11.2.2 Temperature Sensors 491

11.2.3 Accelerometers 497

11.2.4 Strain‐Gauges/Load Cells 498

11.2.5 Acoustic Sensors 500

11.2.6 Linear Variable Differential Transformers (LVDT) 503

11.3 Signal Conditioning 505

11.3.1 Amplifiers 505

11.3.2 Active Filters 505

11.4 Data Acquisition 511

11.4.1 Analog Multiplexer 511

11.4.2 Analog‐to‐Digital Conversion 511

11.5 Grounding Issues 514

11.5.1 Ground Loops 514

11.6 Using PSpice to Demonstrate a Computer‐Based Instrument 516


Further Reading 519

Problems 519

Chapter 12 Principles of Electromechanics 524


12.2 Magnetic Fields 525

12.2.1 Magnetic Flux and Flux Intensity 526

12.2.2 Magnetic Field Intensity 527

12.2.3 The Right‐Hand Rule 527

12.2.4 Forces on Charges by Magnetic Fields 528

12.2.5 Forces on Current‐Carrying Wires 528

12.2.6 Flux Linkages 530

12.2.7 Faraday’s Law and Lenz’s Law 530

12.3 Magnetic Circuits 530

12.3.1 Magnetomotive Force 531

12.3.2 Reluctance 532

12.4 Mutual Inductance and Transformers 538

12.4.1 Mutual Inductance 539

12.4.2 Transformers 542 ©2013 Pearson Education, Inc., Upper Saddle River, NJ 07458. All Rights Reserved

Contents xiii

12.5 Different Types of Transformers 547

12.6 Using PSpice to Simulate Mutual Inductance and Transformers 547


Problems 552

Chapter 13 Electric Machines 557


13.1.1 Features of Electric Machines 558

13.1.2 Classification of Motors 558

13.2 DC Motors 559

13.2.1 Principle of Operation 559

13.2.2 Assembly of a Typical DC Motor 559

13.2.3 Operation of a DC Motor 560

13.2.4 Losses in DC Machines 561

13.3 Different Types of DC Motors 563

13.3.1 Analysis of a DC Motor 563

13.3.2 Shunt‐Connected DC Motor 566

13.3.3 Separately Excited DC Motors 567

13.3.4 Permanent Magnet (PM) DC Motor 568

13.3.5 Series‐Connected DC Motor 571

13.3.6 Summary of DC Motors 573

13.4 Speed Control Methods 573

13.4.1 Speed Control by Varying the Field Current 573

13.4.2 Speed Control by Varying the Armature Current 575

13.5 DC Generators 576

13.5.1 The Architecture and Principle of Operation of a DC Generator 576

13.5.2 emf Equation 577

13.6 Different Types of DC Generators 578

13.6.1 Load Regulation Characteristics of DC Generators 578

13.6.2 Separately Excited DC Generator 579

13.6.3 Shunt‐Connected DC Generator 580

13.7 AC Motors 580

13.7.1 Three‐Phase Synchronous Motors 581

13.7.2 Three‐Phase Induction Motor 584

13.7.3 Losses in AC Machines 591

13.7.4 Power Flow Diagram for an AC Motor 591

13.8 AC Generators 592

13.8.1 Construction and Working 593

13.8.2 Winding Terminologies for the Alternator 593

13.8.3 The emf Equation of an Alternator 595

13.9 Special Types of Motors 597

13.9.1 Single‐Phase Induction Motors 597

13.9.2 Stepper Motors 597 ©2013 Pearson Education, Inc., Upper Saddle River, NJ 07458. All Rights Reserved

xiv Contents

13.9.3 Brushless DC Motors 599

13.9.4 Universal Motors 600

13.10 How is the Most Suitable Motor Selected? 602

13.11 Setup of a Simple DC Motor Circuit Using PSpice 603


Further Reading 611

Problems 611

Chapter 14 Electrical Measurement Instruments 615


14.2 Measurement Errors 616

14.3 Basic Measurement Instruments 619

14.3.1 An Ammeter Built Using a Galvanometer 619

14.3.2 A Voltmeter Built Using a Galvanometer 620

14.3.3 An Ohmmeter Built Using a Galvanometer 621

14.3.4 Multi‐Meters 621

14.4 Time Domain and Frequency Domain 625

14.4.1 The Time Domain 625

14.4.2 The Frequency Domain 626

14.4.3 Time Domain Versus Frequency Domain 627

14.5 The Oscilloscope 628

14.6 The Spectrum Analyzer 633

14.6.1 Adjusting the Spectrum Analyzer’s Display Window 633

14.7 The Function Generator 639


Problems 641

Chapter 15 Electrical Safety 646


15.2 Electric Shock 646

15.2.1 Shock Effects 647

15.2.2 Shock Prevention 649

15.3 Electromagnetic Hazards 649

15.3.1 High‐Frequency Hazards 649

15.3.2 Low‐Frequency Hazards 651

15.3.3 Avoiding Radio Frequency Hazards 655

15.4 Arcs and Explosions 655

15.4.1 Arcs 655

15.4.2 Blasts 657

15.4.3 Explosion Prevention 657

15.5 The National Electric Code 658

15.5.1 Shock Prevention 658

15.5.2 Fire Prevention 663 ©2013 Pearson Education, Inc., Upper Saddle River, NJ 07458. All Rights Reserved

Contents xv


References 666

Problems 666

Appendix A: Solving Linear Equations 671

Appendix B: Laplace Transform 673

Appendix C: Complex Numbers 677

Selected Solutions 683

Index 687



xvii

PREFACE

A multi-disciplinary effort was initiated at Michigan Technological University, with a support

from the U.S. National Science Foundation’s Engineering Education division. The goal was to

create a curriculum that (1) encourages students to pursue the life-long learning necessary to

keep pace with the rapidly-evolving engineering industry and emerging interdisciplinary tech-

nologies, (2) maintains sufficient connection between the students’ chosen engineering fields

and class content; and (3) motivates and excite the students about the importance of EE concepts

to their discipline and career.

Seven faculty members across different departments contributed to this process.

Participating departments included: electrical engineering, chemical engineering, civil and en-

vironmental engineering, mechanical engineering, biomedical engineering, and the education

division of the cognitive and learning science department. The group’s curriculum reform ef-

forts were informed by a nationwide survey of engineering schools. The survey outcomes were

analyzed to fine tune different curriculum options for this course for different engineering disci-

plines. Then, those options were integrated to create the final draft of the curriculum. The final

draft of the curriculum was used as a layout to create a new textbook for this course.

Although no single text can perfectly meet the needs of every institution, diverse topics

have been included to address the mixed survey response and allow this book to address the

needs of lecturers in different institutions worldwide. The resulting textbook creates a proto-

type curriculum available to electrical engineering departments that are charged with providing

an introduction to electrical engineering for non-EE majors. The goals of this new curriculum

are to be attractive, motivational, and relevant to students by creating many application-based

problems; and provide the optimal level of both range and depth of coverage of EE topics in a

curriculum package.

The book features:

a. Application-based examples: A large number of application-based examples were

selected from different engineering fields and are included in each chapter. They aim

to bridge EE and diverse non-EE areas. These examples help to address the question:

“why I should take this course?” Non-EE students will better understand: (1) why they

should learn how to solve circuits; and; (2) what are the applications of solving circuits in

mechanical, chemical, and civil engineering areas.

b. PSpice lectures, examples, and problems: The text offers a distributed approach for

learning PSpice. A PSpice component is integrated in many chapters. Chapter 2 provides

an initial tutorial, and new skills are added in Chapters 3 – 11 . This part includes lectures

that teach students how to use PSpice and can be considered as an embedded PC-based lab

for the course. In addition, many PSpice-specific examples have been developed, which

help students better understand the process of building a circuit and getting the desired

results. There are also many end-of-chapter PSpice problems.

c. Innovative chapters: Based on our nationwide survey, the topics in these chapters have

been highlighted by many professionals as important topics for this course. It should be

noted that each instructor has the liberty to include or exclude some of these topics from

his/her curriculum. Some topics include:

• Chapter 1 —Case Study: This chapter presents the applications of electrical engineering

components in mechanical engineering, chemical engineering, and civil engineer-

ing through real life scenarios. A bridge across these case studies and the topics that

will be covered later in the book is maintained. The goal is to better motivate students

by placing the concepts of electrical engineering in the context of their chosen fields

of study. Each section of this chapter was been prepared by a different member of the

faculty at Michigan Tech who contributed to the NSF project. ©2013 Pearson Education, Inc., Upper Saddle River, NJ 07458. All Rights Reserved

xviii Preface

• Chapter 7 —Frequency Response with MATLAB and PSpice: This chapter discusses

the frequency response of circuits and introduces different types of filters and uses

MATLAB and PSpice examples and end-of chapter problems. This chapter creates an

opportunity for students to learn some features of MATLAB software. In other words,

this chapter promotes an integrated study using both PSpice and MATLAB.

• Power Coverage: Chapters 9, 12, 13— Based on our nationwide survey, and motivated

by concerns about global warming and the need for clean energy, industry respondents

requested a more thorough treatment of power. Thus, power coverage is supported by

three chapters. Chapter 9 introduces the concept of three-phase systems, transmission

lines, their equivalent circuits, and power transfer. Chapter 12 studies another impor-

tant topic of energy transfer—transformers. Finally Chapter 13 studies the topic of

motors and generators. This chapter offers the concept of motors and generators in a

clear and concise approach. The chapter introduces applications of motors and genera-

tors and introduces many applications of both.

• Chapter 15 —Electrical Safety: This unique chapter discusses interesting electric

safety topics useful in the daily life of consumers or engineers working in the field.

d. Examples and sorted end-of-chapter problems: The book comes with more than 1100

examples and end-of-chapter problems (solutions included). End-of-chapter problems are

sorted to help instructors select basic, average, and difficult problems.

e. A complete solution manual: A complete solutions manual for all problems will be avail-

able via download for all adopting professors.


ACKNOWLEDGMENTS

Professor William Bulleit (Civil and Environmental Engineering Department, Michigan Tech),

Professor Tony Rogers (Chemical Engineering Department, Michigan Tech) and Professor Harold

Evensen (Mechanical Engineering, Engineering Mechanics Department, Michigan Tech) are the

authors of chapter one. The research on this National Science Foundation project was conducted

with the support of many faculty members. Here, in addition to Professor Bulleit, Professor

Rogers and Professor Evensen, I should acknowledge the efforts of Professor Kedmon Hungwe

(Education Department, Michigan Tech), Mr. Glen Archer (Electrical and Computer Engineering

Department, Michigan Tech), Professor Corina Sandu (Mechanical Engineering Department,

Virginia Tech), Professor David Nelson (Mechanical Engineering Department, University of

South Alabama), Professor Sheryl Sorby (Mechanical Engineering, Engineering Mechanics

Department, Michigan Tech), and Professor Valorie Troesch (Institute for Interdisciplinary

Studies, Michigan Tech). The preparation of the book was not possible without the support of

many graduate students that include Luke Mounsey, Xiukui Li, Taha Abdelhakim, Shu G. Ting,

Wenjie Xu, Zhonghai Wang, Babak Bastaami, Manaas Majumdar, Abdelhaseeb Ahmed, Daw

Don Cheam, Jafar Pourrostam and Greg Price. I would like to thank all of them. Moreover, I

should thank the support of the book’s grand reviewer Mr. Peter A. Larsen (Sponsored Programs,

Michigan Tech) which improved the quality of its presentation. In addition, I should acknowl-

edge many colleagues whose names are listed below, who reviewed the book and provided me

with invaluable comments and feedback.

Paul Crilly—University of TennesseeTimothy Peck—University of IllinoisGeorge Shoane—Rutgers UniversityZiqian Liu—SUNY Maritime CollegeRalph Tanner—Western Michigan University

Douglas P. Looze—University of Massachusetts, AmherstJaime Ramos-Salas—University of Texas, Pan American

Dale Dolan—California Polytechnic State University, San Luis ObispoMunther Hassouneh—University of MarylandJacob Klapper—New Jersey Institute of TechnologyThomas M. Sullivan—Carnegie Mellon University

Vijayakumar Bhagavatula—Carnegie Mellon UniversityS. Hossein Mousavinezhad—Idaho State University

Alan J. Michaels—Harris Corporation

Sandra Soto-Caban—Muskingum University

Wei Pan—Idaho State University

Finally, I should acknowledge the support of late Professor Derek Lile, the former department head

of Electrical and Computer Engineering of Colorado State University, while I was creating the

ideas of this project while I was a Ph.D. candidate at Colorado State University, Ft. Collins, CO.

S. A. Reza ZekavatMichigan Technological University

xix©2013 Pearson Education, Inc., Upper Saddle River, NJ 07458. All Rights Reserved


Electrical EngineeringConcepts and Applications



Documents

Electrical EngineeringChapter 2 Fundamentals of Electric Circuits 13 2.1 Introduction 13 2.2 Charge and Current 15 2.3 Voltage 17 2.4 Respective Direction of Voltage and Current 18