2.-Network-Theory_Updated_FINAL_with-Link.pdf

Network Theory Published By: Physics Wallah ISBN: 978-93-94342-39-2 Mobile App: Physics Wallah (Available on Play Store) Website: www.pw.live Email: [email protected] Rights All rights will be reserved by Publisher. No part of this book...

Network Theory Published By: Physics Wallah ISBN: 978-93-94342-39-2 Mobile App: Physics Wallah (Available on Play Store) Website: www.pw.live Email: [email protected] Rights All rights will be reserved by Publisher. No part of this book may be used or reproduced in any manner whatsoever without the written permission from author or publisher. In the interest of student's community: Circulation of soft copy of Book(s) in PDF or other equivalent format(s) through any social media channels, emails, etc. or any other channels through mobiles, laptops or desktop is a criminal offence. Anybody circulating, downloading, storing, soft copy of the book on his device(s) is in breach of Copyright Act. Further Photocopying of this book or any of its material is also illegal. Do not download or forward in case you come across any such soft copy material. Disclaimer A team of PW experts and faculties with an understanding of the subject has worked hard for the books. While the author and publisher have used their best efforts in preparing these books. The content has been checked for accuracy. As the book is intended for educational purposes, the author shall not be responsible for any errors contained in the book. The publication is designed to provide accurate and authoritative information with regard to the subject matter covered. This book and the individual contribution contained in it are protected under copyright by the publisher. (This Module shall only be Used for Educational Purpose.)  Design Against Static Load NETWORK THEORY INDEX 1. Basic Concepts of Networks................................................................................................. 2.1 – 2.19 2. Two Port Networks................................................................................................................ 2.20 – 2.29 3. Network Theorem................................................................................................................ 2.30 – 2.34 4. Transient Analysis................................................................................................................. 2.35 – 2.43 5. Sinusoidal Steady State Analysis.......................................................................................... 2.44 – 2.46 6. Resonance............................................................................................................................ 2.47 – 2.53 7. Complex Power.................................................................................................................... 2.54 – 2.57 8. Magnetic Coupling............................................................................................................... 2.58 – 2.61 GATE-O-PEDIA ELECTRONICS AND COMMUNICATION ENGINEERING  Design Against Static Load 1 1.1 Introduction BASIC CONCEPTS OF NETWORKS Network theory is the study of solving the problems of electric circuits or electric networks. An electric circuit contains a closed path for providing a flow of electrons from a voltage source or current source. The elements present in an electric circuit will be in series connection, parallel connection, or in any combination of series and parallel connections and an electric network need not contain a closed path for providing a flow of electrons from a voltage source or current source. Hence, we can conclude that “all electric circuits are electric networks” but the converse need not be true. 1.1.1. Types of Network Elements Different types of network elements are 1. Linear Elements and Non-linear Elements. 2. Bilateral Elements and Unilateral Elements. 3. Active Elements and Passive Elements. 4. Time Invariant and Time Variant Elements. 5. Lumped and Distributed Elements. 1. Linear Elements Characteristics of linear elements always passes through the origin in the form of straight line. Linear Example of linear elements: All basic electrical elements are linear (R, L, C). GATE WALLAH ELECTRONICS & COMMUNICATION HANDBOOK 2.1  Network Theory 2. Non-Linear Elements Non linear Non linear Example of non-linear elements : All electronic devices are non-linear (Diode, MOSFET, JFET). GATE WALLAH ELECTRONICS & COMMUNICATION HANDBOOK 2.2  Network Theory 2. Bilateral and Unilateral Elements (i) In case of V-I plane, characteristics of bilateral elements offer same impedance throughout the characteristics. (ii) In case of V-I plane, characteristics of unilateral elements offer different impedance in different origin. (iii) In case of generalized plane, characteristics of bilateral elements is always symmetrical about origin. Characteristics are same in either I and III quadrant or II and IV quadrant. (a) odd function (b) odd function (c) even function (d) even function (e) odd function Note: L = Linear, NL = Non-linear, B = Bilateral, U = Unilateral GATE WALLAH ELECTRONICS & COMMUNICATION HANDBOOK 2.3  Network Theory All linear elements are bilateral but reverse is not true. Network element Bilateral/Unilateral Device Element Bilateral/Unilateral R Bilateral Diode Unilateral L Bilateral BJT Unilateral C Bilateral JFET Unilateral 3. Active and Passive Elements (i) In case of V-I plane, characteristics of passive element always have positive impedance where as active element offeres negative impedance. (ii) Passive elements absorb the energy whereas active elements deliver the energy. (iii) Active element controls, the flow of energy whereas passive elements dissipate or store the energy. (iv) Elements having capability of delivering the energy is referred as active elements. Examples of active elements : (a) Voltage source (b) Current source (c) Generator (d) Biased Transistors (e) Operational Amplifier Note: All dependent sources are considers as an active element. GATE WALLAH ELECTRONICS & COMMUNICATION HANDBOOK 2.4  Network Theory Generally, inductors and capacitors are passive elements. As they can not deliver the energy independently for long time? They can give energy only at the time of discharge. 4. Lumped and Distributed Elements (i) Physically separated elements in a network is referred as lumped elements. (ii) If elements are distributed along the line, then it is referred as distributed elements. (iii) Concept of circuit theory is based on lumped elements. (iv) Concept of field theory is based on distributed elements. Network Elements Passive Condition Active Condition R R0 R