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Fundamentals of Electrical Circuits

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Fundamentals of Electrical Circuits Fundamentals of Electrical Circuits Printed September 2016 First printed in 2007 Background and Acknowledgements This material is intended for the first course sequence in Electrical Engineering focused on Electrical Circuit Analysis and Design. The content is derived from the author’s educational, engineering and management career, and teaching experience. Additionally, the following resources have informed the development of content and format: Katz, R. Contemporary Logic Design . (2005) Pearson. Wakerly, I. Digital Design . (2001) Prentice Hall. Sandige, R. Digital Design Essentials . (2002) Prentice Hall. Nilsson, J. Electrical Circuits . (2004) Pearson. MathWorks. MATLAB Reference Material Version R2000a . (2007) MathWorks I would like to extend special thanks to the many students and colleagues for their contributions in making this material a more effective learning tool. Further, I would invite the reader to forward corrections, additional topics, examples and problems to me for future updates. Thanks, Izad Khormaee www.EngrCS.com © 2009 Izad Khormaee, All Rights Reserved. Fundamentals of Electrical Circuits, V3.6 Page 2 Table of Contents CHAPTER 1. INTRODUCTION .............................................................................................................................. 6 1.1. OVERVIEW OF ELECTRICAL ENGINEERING .......................................................................................................... 7 1.2. PROBLEM SOLVING .............................................................................................................................................. 8 1.3. SYSTEMS OF UNITS .............................................................................................................................................. 9 1.4. CHARGE , CURRENT AND VOLTAGE .................................................................................................................... 11 1.5. CIRCUIT MODEL ................................................................................................................................................ 13 1.6. POWER AND ENERGY ......................................................................................................................................... 15 1.7. SUMMARY ......................................................................................................................................................... 19 1.8. ADDITIONAL RESOURCES .................................................................................................................................. 20 1.9. PROBLEMS ......................................................................................................................................................... 21 CHAPTER 2. BASIC LAWS ................................................................................................................................... 22 2.1. IDEAL VOLTAGE & CURRENT SOURCES ............................................................................................................. 23 2.2. OHM ’S LAW ....................................................................................................................................................... 26 2.3. CIRCUIT MODELING AND ANALYSIS .................................................................................................................. 28 2.4. KIRCHHOFF ’S LAWS .......................................................................................................................................... 30 2.5. SUMMARY ......................................................................................................................................................... 39 2.6. ADDITIONAL RESOURCES .................................................................................................................................. 40 2.7. PROBLEMS ......................................................................................................................................................... 41 CHAPTER 3. ANALYSIS OF RESISTIVE CIRCUITS ...................................................................................... 42 3.1. SERIES RESISTORS CONFIGURATION .................................................................................................................. 43 3.2. PARALLEL RESISTORS CONFIGURATION ............................................................................................................ 45 3.3. VOLTAGE AND CURRENT DIVIDERS ................................................................................................................... 50 3.4. MEASUREMENT INSTRUMENTS .......................................................................................................................... 55 3.5. DELTA AND WYE CONFIGURATIONS ................................................................................................................. 59 3.6. SUMMARY ......................................................................................................................................................... 61 3.7. ADDITIONAL RESOURCES .................................................................................................................................. 62 3.8. PROBLEMS ......................................................................................................................................................... 63 CHAPTER 4. CIRCUIT ANALYSIS/MODELING TECHNIQUES .................................................................. 64 4.1. INTRODUCTION .................................................................................................................................................. 65 4.2. NODE -VOLTAGE METHOD (B ASED ON KCL) .................................................................................................... 67 4.3 MESH -CURRENT METHOD (BASED ON KVL) ...................................................................................................... 72 4.4. NODE -VOLTAGE AND MESH -CURRENT COMPARISON ....................................................................................... 78 4.5. SOURCE TRANSFORMATION ............................................................................................................................... 80 4.6. THEVENIN & NORTON EQUIVALENTS ................................................................................................................ 84 4.7. DELIVERING MAXIMUM POWER ........................................................................................................................ 96 4.8. SUPER -POSITION PRINCIPLE .............................................................................................................................. 98 4.9. SENSITIVITY ANALYSIS ................................................................................................................................... 101 4.10. SUMMARY ..................................................................................................................................................... 102 4.11. ADDITIONAL RESOURCES .............................................................................................................................. 103 4.12. PROBLEMS ..................................................................................................................................................... 104 CHAPTER 5. OPERATIONAL AMPLIFIER .................................................................................................... 105 5.1. TRANSISTOR OVERVIEW ................................................................................................................................. 106 5.2. OPERATIONAL AMPLIFIER (O P AMP ) ............................................................................................................... 109 5.3. OP AMP APPLICATIONS ................................................................................................................................... 113 5.4. COMMON MODE (CM ) VS . DIFFERENTIAL MODE (DM ) ..................................................................................... 121 5.5. OP AMP DC MODEL ........................................................................................................................................ 123 5.6. SUMMARY ....................................................................................................................................................... 126 5.7. ADDITIONAL RESOURCES ................................................................................................................................ 127 Fundamentals of Electrical Circuits, V3.6 Page 3 5.8. PROBLEMS ....................................................................................................................................................... 128 CHAPTER 6. CAPACITORS AND INDUCTORS ............................................................................................. 129 6.1. PASSIVE ELEMENTS ......................................................................................................................................... 130 6.2. INDUCTOR, L ................................................................................................................................................... 131 6.3. SERIES AND PARALLEL INDUCTORS ................................................................................................................. 135 6.4. CAPACITOR , C ................................................................................................................................................
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