Transformer Magnetics
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Basic Magnetic Measurement Methods
Basic magnetic measurement methods Magnetic measurements in nanoelectronics 1. Vibrating sample magnetometry and related methods 2. Magnetooptical methods 3. Other methods Introduction Magnetization is a quantity of interest in many measurements involving spintronic materials ● Biot-Savart law (1820) (Jean-Baptiste Biot (1774-1862), Félix Savart (1791-1841)) Magnetic field (the proper name is magnetic flux density [1]*) of a current carrying piece of conductor is given by: μ 0 I dl̂ ×⃗r − − ⃗ 7 1 - vacuum permeability d B= μ 0=4 π10 Hm 4 π ∣⃗r∣3 ● The unit of the magnetic flux density, Tesla (1 T=1 Wb/m2), as a derive unit of Si must be based on some measurement (force, magnetic resonance) *the alternative name is magnetic induction Introduction Magnetization is a quantity of interest in many measurements involving spintronic materials ● Biot-Savart law (1820) (Jean-Baptiste Biot (1774-1862), Félix Savart (1791-1841)) Magnetic field (the proper name is magnetic flux density [1]*) of a current carrying piece of conductor is given by: μ 0 I dl̂ ×⃗r − − ⃗ 7 1 - vacuum permeability d B= μ 0=4 π10 Hm 4 π ∣⃗r∣3 ● The Physikalisch-Technische Bundesanstalt (German national metrology institute) maintains a unit Tesla in form of coils with coil constant k (ratio of the magnetic flux density to the coil current) determined based on NMR measurements graphics from: http://www.ptb.de/cms/fileadmin/internet/fachabteilungen/abteilung_2/2.5_halbleiterphysik_und_magnetismus/2.51/realization.pdf *the alternative name is magnetic induction Introduction It -
Electrostatics Vs Magnetostatics Electrostatics Magnetostatics
Electrostatics vs Magnetostatics Electrostatics Magnetostatics Stationary charges ⇒ Constant Electric Field Steady currents ⇒ Constant Magnetic Field Coulomb’s Law Biot-Savart’s Law 1 ̂ ̂ 4 4 (Inverse Square Law) (Inverse Square Law) Electric field is the negative gradient of the Magnetic field is the curl of magnetic vector electric scalar potential. potential. 1 ′ ′ ′ ′ 4 |′| 4 |′| Electric Scalar Potential Magnetic Vector Potential Three Poisson’s equations for solving Poisson’s equation for solving electric scalar magnetic vector potential potential. Discrete 2 Physical Dipole ′′′ Continuous Magnetic Dipole Moment Electric Dipole Moment 1 1 1 3 ∙̂̂ 3 ∙̂̂ 4 4 Electric field cause by an electric dipole Magnetic field cause by a magnetic dipole Torque on an electric dipole Torque on a magnetic dipole ∙ ∙ Electric force on an electric dipole Magnetic force on a magnetic dipole ∙ ∙ Electric Potential Energy Magnetic Potential Energy of an electric dipole of a magnetic dipole Electric Dipole Moment per unit volume Magnetic Dipole Moment per unit volume (Polarisation) (Magnetisation) ∙ Volume Bound Charge Density Volume Bound Current Density ∙ Surface Bound Charge Density Surface Bound Current Density Volume Charge Density Volume Current Density Net , Free , Bound Net , Free , Bound Volume Charge Volume Current Net , Free , Bound Net ,Free , Bound 1 = Electric field = Magnetic field = Electric Displacement = Auxiliary -
Mutual Inductance and Transformer Theory Questions: 1 Through 15 Lab Exercise: Transformer Voltage/Current Ratios (Question 61)
ELTR 115 (AC 2), section 1 Recommended schedule Day 1 Topics: Mutual inductance and transformer theory Questions: 1 through 15 Lab Exercise: Transformer voltage/current ratios (question 61) Day 2 Topics: Transformer step ratio Questions: 16 through 30 Lab Exercise: Auto-transformers (question 62) Day 3 Topics: Maximum power transfer theorem and impedance matching with transformers Questions: 31 through 45 Lab Exercise: Auto-transformers (question 63) Day 4 Topics: Transformer applications, power ratings, and core effects Questions: 46 through 60 Lab Exercise: Differential voltage measurement using the oscilloscope (question 64) Day 5 Exam 1: includes Transformer voltage ratio performance assessment Lab Exercise: work on project Project: Initial project design checked by instructor and components selected (sensitive audio detector circuit recommended) Practice and challenge problems Questions: 66 through the end of the worksheet Impending deadlines Project due at end of ELTR115, Section 3 Question 65: Sample project grading criteria 1 ELTR 115 (AC 2), section 1 Project ideas AC power supply: (Strongly Recommended!) This is basically one-half of an AC/DC power supply circuit, consisting of a line power plug, on/off switch, fuse, indicator lamp, and a step-down transformer. The reason this project idea is strongly recommended is that it may serve as the basis for the recommended power supply project in the next course (ELTR120 – Semiconductors 1). If you build the AC section now, you will not have to re-build an enclosure or any of the line-power circuitry later! Note that the first lab (step-down transformer circuit) may serve as a prototype for this project with just a few additional components. -
Chapter 1 Magnetic Circuits and Magnetic Materials
Chapter 1 Magnetic Circuits and Magnetic Materials The objective of this course is to study the devices used in the interconversion of electric and mechanical energy, with emphasis placed on electromagnetic rotating machinery. The transformer, although not an electromechanical-energy-conversion device, is an important component of the overall energy-conversion process. Practically all transformers and electric machinery use ferro-magnetic material for shaping and directing the magnetic fields that acts as the medium for transferring and converting energy. Permanent-magnet materials are also widely used. The ability to analyze and describe systems containing magnetic materials is essential for designing and understanding electromechanical-energy-conversion devices. The techniques of magnetic-circuit analysis, which represent algebraic approximations to exact field-theory solutions, are widely used in the study of electromechanical-energy-conversion devices. §1.1 Introduction to Magnetic Circuits Assume the frequencies and sizes involved are such that the displacement-current term in Maxwell’s equations, which accounts for magnetic fields being produced in space by time-varying electric fields and is associated with electromagnetic radiations, can be neglected. Z H : magnetic field intensity, amperes/m, A/m, A-turn/m, A-t/m Z B : magnetic flux density, webers/m2, Wb/m2, tesla (T) Z 1 Wb =108 lines (maxwells); 1 T =104 gauss Z From (1.1), we see that the source of H is the current density J . The line integral of the tangential component of the magnetic field intensity H around a closed contour C is equal to the total current passing through any surface S linking that contour. -
Power Management Consortium (PMC) Nuggets
CPES ANNUAL REPORT 2020 103 Power Management Consortium (PMC) Nuggets 104 Low Loss Integrated Inductor and Transformer Structure and Application 114 Design Optimization of an Unregulated LLC Converter with Integrated in Regulated LLC Converter for 48 V Bus Converter Magnetics for a Two-Stage, 48 V VRM 105 Magnetic Integration of Matrix Transformer with a Highly Controllable 115 Wide-Voltage Range, High-Efficiency Sigma Converter 48 V VRM with Leakage Inductance Integrated Magnetics 106 Control Technique for CRM-Based, High-Frequency, 116 Modeling and Control for a 48 V/1 V Sigma Converter for Very Fast Soft-Switching Three-Phase Inverter Under Grid Fault Condition Transient Response 107 Critical Conduction Mode-Based, High-Frequency, Single-Phase 117 A Two-Stage Rail Grade DC-DC Converter Based on a GaN Device Transformerless PV Inverter 118 Design-Oriented Equivalent Circuit Model for Resonant Converters 108 Transmitter Coil Design for Free-Positioning Omnidirectional Wireless 119 Critical-Conduction-Mode-Based Soft-Switching Modulation for Three- Power Transfer System Phase PV Inverters with Reactive Power Transfer Capability 109 Shielding Study of a 6.78 MHz Omnidirectional Wireless Power Transfer 120 Improved Three-Phase Critical-Mode-Based Soft-Switching Modulation System Technique with Low Leakage Current for PV Inverter Application 110 The LCCL-LC Resonant Converter and Its Soft Switching Realization for 121 Balance Technique for CM Noise Reduction in Critical-Mode-Based Three- Omnidirectional Wireless Power Transfer Systems Phase -
Design of Magnetic Circuits
Design of Magnetic Circuits Fundamental Equations Circuit laws similar to those of electric circuits apply in magnetic circuits as well. That is, a magnetic circuit can be replaced by an equivalent electric circuit for Ohm’s Law to be applied. If the magnetomotive force of a magnet is F and the total magnetic flux is Φt, and assuming the magnetic resistance (reluctance) of the circuit is R, then the following equation is valid. (1) Assuming the vacant length of the circuit as ℓg and the vacant cross-sectional area as ag, the magnetic resistance is then given by the following equation. (2) μ is the magnetic permeability of the magnetic path and is equivalent to the magnetic permeability μ0 of a vacuum in the case of air. (μ0=4π×10-7 [H/m]) Yoke 〈Figure 7〉 Although the current in an electric circuit rarely leaks outside the circuit, as the difference in the magnetic permeability between the conductor yoke and insulated area in a magnetic circuit is not very large, leakage of the magnetic flux also becomes large in reality. The amount of the magnetic flux leakage is expressed by the leakage factor σ, which is the ratio of the total magnetic flux Φt generated in the magnetic circuit to the effective magnetic flux Φg of the vacant space. (3) In addition, the loss in the magnetic flux due to the joints in the magnetic circuit must also be taken into consideration. This is represented by the reluctance factor f. Since the leakage factor σ is equivalent to the increase in the vacant space area, and the reluctance factor f refers to the correction coefficient of the vacant space length, the corrected magnetic resistance becomes as follows. -
Fall 2011 Meeting Minutes Boston MA November 3,2011
IEEE/PES Transformers Committee Fall 2011 Meeting Minutes Boston MA November 3,2011 Unapproved IEEE/PES Transformers Committee Meeting Fall 2011 Boston MA Committee Members and Guests Registered for the Spring 2011 Meeting Albers, Timothy: II Bertolini, Edward: AP - LM Campbell, James: II Allaway, Dave: II Berube, Jean-Noel: II Carlos, Arnaldo: AP Allaway, Marcene: SP Betancourt, Enrique: CM Caronia, Paul: II Allen, Jerry: AP Bhatia, Paramjit: II Caskey, John: AP Allen, Abbey: II Binder, Wallace: CM Caskey, Melissa: G Alton, Henry: II Bishop Jr, Wayne: II Castellanos, Juan: CM Amos, Richard: CM Bishop, Cherie: SP Castillo, Alonso: II Amos, Norann: SP Blackburn, Gene: CM Castillo, Karla: SP Anderson, Gregory: CM Blackburn, Martha: SP Chadderdon, Philip: II Anderson, Jeffrey: II Blackmon, Jr., James: AP Cheim, Luiz: AP Angell, Don: AP Blackmon, Donna: SP Cherry, Donald: CM Ansari, Tauhid: AP Blaydon, Daniel: CM Chiodo, Vincent: II Anthony, Stephen: II Boettger, William: CM Chisholm, Paul: AP Antosz, Stephen: CM Boettger, Pat: SP Chiu, Bill: CM Armstrong, James: AP Bolliger, Alain: AP Lu, Minnie: SP Arpino, Carlo: CM Bolliger, Dominique: SP Chmiel, Frank: AP Arpino, Tina: SP Boman, Paul: CM Choinski, Scott: AP Asano, Roberto: AP Borowitz, James: II Bartholomew, Kathy: SP Atef, Kahveh: II Botti, Michael: II Christodoulou, Larry: II Averitt, Ralph: II Botti, Nicole: SP Chrobak, John: II Ayers, Donald: CM Bozich, Bradford: II Chu, Donald: CM Bae, Yongbae: II Bradford, Ira: II Claiborne, C. Clair: CM Ballard, Jay: AP Brady, Ryan: II Cocchiarale, -
Application Note AN-1024 Flyback Transformer Design for The
Application Note AN-1024 Flyback Transformer Design for the IRIS40xx Series Table of Contents Page 1. Introduction to Flyback Transformer Design ...............................................1 2. Power Supply Design Criteria Required .......................................................2 3. Transformer Design Process.........................................................................2 4) Transformer Construction .............................................................................9 4.1) Transformer Materials..................................................................................10 4.2) Winding Styles.............................................................................................12 4.3) Winding Order..............................................................................................12 4.4) Multiple Outputs...........................................................................................12 4.5) Leakage Inductance ....................................................................................13 5) Transformer Core Types ..............................................................................14 6) Wire Table .....................................................................................................16 7) References ....................................................................................................17 8) Transformer Component Sources...............................................................17 One of the most important factors in the design of -
Module 3 : MAGNETIC FIELD Lecture 20 : Magnetism in Matter
Module 3 : MAGNETIC FIELD Lecture 20 : Magnetism in Matter Objectives In this lecture you will learn the following Study magnetic properties of matter. Express Ampere's law in the presence of magnetic matter. Define magnetization and H-vector. Understand displacement current. Assemble all the Maxwell's equations together. Study properties and propagation of electromagnetic waves in vacuum. Magnetism in Matter In our discussion on electrostatics, we have seen that in the presence of an electric field, a dielectric gets polarized, leading to bound charges. The polarization vector is, in general, in the direction of the applied electric field. A similar phenomenon occurs when a material medium is subjected to an external magnetic field. However, unlike the behaviour of dielectrics in electric field, different types of material behave in different ways when an external magnetic field is applied. We have seen that the source of magnetic field is electric current. The circulating electrons in an atom, being tiny current loops, constitute a magnetic dipole with a magnetic moment whose direction depends on the direction in which the electron is moving. An atom as a whole, may or may not have a net magnetic moment depending on the way the moments due to different elecronic orbits add up. (The situation gets further complicated because of electron spin, which is a purely quantum concept, that provides an intrinsic magnetic moment to an electron.) In the absence of a magnetic field, the atomic moments in a material are randomly oriented and consequently the net magnetic moment of the material is zero. However, in the presence of a magnetic field, the substance may acquire a net magnetic moment either in the direction of the applied field or in a direction opposite to it. -
Tesla's Coil. a Toy Or Useful Thing in the Life of Radio Engineering?
УДК 537 Ільчук Д.Р. Tesla's coil. A toy or useful thing in the life of radio engineering? Вінницький національний технічний університет Аннотація. У цій статті, подан опис такого приладу як Котушка Тесли. Наведені її характеристики, принцип роботи, історія створення та значення в сучасному житті. Також описані процеси створення власноруч та розсуди про практичність даного виробу у реальному житті. Ключові слова: Котушка індуктивності, висока напруга, Нікола Тесла, радіотехніка, електрична дуга. Abstract. This article contains a description of the device as a Tesla coil. These characteristics of the principle of history and value creation in modern life. Also describes the process of creating his own judge and practicality of this product in real life. Keywords: Inductor, high voltage, Nikola Tesla, radio, electric arc. I.Introduction Perhaps in the life of every student comes a time when it begins to be interested in their field. In some it comes in the first year, someone on last. At the beginning of the 3rd year I finally decided to solder something with their hands. The choice immediately fell on Tesla coil. But is this thing so important, whether it is only a toy, which is impossible to do anything useful? Let us know about it. II. Summary The Tesla coil is an electrical resonant transformer circuit designed by inventor Nikola Tesla around 1891 as a power supply for his "System of Electric Lighting".It is used to produce high-voltage, low-current, high frequency alternating-current electricity. Tesla experimented with a number of different configurations consisting of two, or sometimes three, coupled resonant electric circuits. -
THE ULTIMATE Tesla Coil Design and CONSTRUCTION GUIDE the ULTIMATE Tesla Coil Design and CONSTRUCTION GUIDE
THE ULTIMATE Tesla Coil Design AND CONSTRUCTION GUIDE THE ULTIMATE Tesla Coil Design AND CONSTRUCTION GUIDE Mitch Tilbury New York Chicago San Francisco Lisbon London Madrid Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto Copyright © 2008 by The McGraw-Hill Companies, Inc. All rights reserved. Manufactured in the United States of America. Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher. 0-07-159589-9 The material in this eBook also appears in the print version of this title: 0-07-149737-4. All trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intention of infringement of the trademark. Where such designations appear in this book, they have been printed with initial caps. McGraw-Hill eBooks are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs. For more information, please contact George Hoare, Special Sales, at [email protected] or (212) 904-4069. TERMS OF USE This is a copyrighted work and The McGraw-Hill Companies, Inc. (“McGraw-Hill”) and its licensors reserve all rights in and to the work. Use of this work is subject to these terms. Except as permitted under the Copyright Act of 1976 and the right to store and retrieve one copy of the work, you may not decompile, disassemble, reverse engineer, reproduce, modify, create derivative works based upon, transmit, distribute, disseminate, sell, publish or sublicense the work or any part of it without McGraw-Hill’s prior consent. -
Power Processing, Part 1. Electric Machinery Analysis
DOCONEIT MORE BD 179 391 SE 029 295,. a 'AUTHOR Hamilton, Howard B. :TITLE Power Processing, Part 1.Electic Machinery Analyiis. ) INSTITUTION Pittsburgh Onii., Pa. SPONS AGENCY National Science Foundation, Washingtcn, PUB DATE 70 GRANT NSF-GY-4138 NOTE 4913.; For related documents, see SE 029 296-298 n EDRS PRICE MF01/PC10 PusiPostage. DESCRIPTORS *College Science; Ciirriculum Develoiment; ElectricityrFlectrOmechanical lechnology: Electronics; *Fagineering.Education; Higher Education;,Instructional'Materials; *Science Courses; Science Curiiculum:.*Science Education; *Science Materials; SCientific Concepts ABSTRACT A This publication was developed as aportion of a two-semester sequence commeicing ateither the sixth cr'seventh term of,the undergraduate program inelectrical engineering at the University of Pittsburgh. The materials of thetwo courses, produced by a ional Science Foundation grant, are concernedwith power convrs systems comprising power electronicdevices, electrouthchanical energy converters, and associated,logic Configurations necessary to cause the system to behave in a prescribed fashion. The emphisis in this portionof the two course sequence (Part 1)is on electric machinery analysis. lechnigues app;icable'to electric machines under dynamicconditions are anallzed. This publication consists of sevenchapters which cW-al with: (1) basic principles: (2) elementary concept of torqueand geherated voltage; (3)tile generalized machine;(4i direct current (7) macrimes; (5) cross field machines;(6),synchronous machines; and polyphase