DOCSLIB.ORG

The Invention of the Electric Dynamo

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Invention of the Electric Dynamo The Invention of the Electromotive Engine B. J. G. van der Kooij This case study is part of the research work being completed in preparation for a doctorate-dissertation to be submitted to the University of Technology, Delft, The Netherlands (www.tudelft.nl). It is part of a series of case studies about “Innovation” under the title “The Invention Series.” About the text—This is a scholarly case study describing the historic developments that resulted in electromotive engines. It is based on a large number of historic and contemporary sources. As we did not conduct any research into primary sources, we made use of the efforts of numerous others by citing them quite extensively to preserve the original character of their contributions. Where possible we identified the individual authors of the citations. When an author is not identifiable, we identified the source of the text. Facts that are considered to be of a general character in the public domain are not cited. About the pictures—Many of the pictures used in this study were found on websites accessed through the Internet. Where possible they were traced to their origins, and the source is indicated. As most photos are past the age where copyright would apply, we feel that we make fair use of the pictures to illustrate the scholarly case, and this use is not an infringement of copyright. Copyright © 2015 B. J. G. van der Kooij Cover art is line drawing of Bush’ electric dynamo (US Patent № 189.997) and Dobrowolsky’s electric motor (US patent № 469.515). (courtesy USPTO) Version 1.1 (March 2015) All rights reserved. ISBN: 1503095878 ISBN-13: 978-1503095878 The Invention of the Electro-motive Engine Contents Contents ............................................................................................ i Preface ............................................................................................. v About the Invention Series ................................................................... vii About our research .............................................................................. viii About this case study ..............................................................................x Context for the discoveries ................................................................ 1 The nineteenth century .......................................................................... 3 A time of changes: political, economic, social, technical......................... 3 Science discovers and applies electricity ............................................... 24 Electricity as phenomenon: the nature of lightning ............................... 32 Electricity explored ...................................................................................... 38 Creation of electromagnetic power ........................................................... 63 Electrochemistry: the wet cell .................................................................... 66 The power of lightning understood ...................................................... 69 The invention of the electric DC motor ........................................... 71 The direct current electric motor ......................................................... 71 The electromagnetic reciprocal engine ..................................................... 72 The electromagnetic rotatory engine ........................................................ 76 The invention of the DC motor ................................................................ 82 A cluster of innovations for the DC motor ............................................ 85 i B.J.G. van der Kooij The invention of the electric dynamo .............................................. 87 Electricity generators: the dry battery ................................................... 88 Principle of the dynamo: DC/AC ............................................................. 90 Early magneto-electric dynamos ............................................................... 91 The self-exciting electric dynamo ............................................................ 108 Some of the later dynamos ....................................................................... 123 From Component to System ................................................................... 125 The invention of the magneto-electric dynamo .................................... 128 A cluster of innovation for the dynamo ................................................. 129 The Electric Revolution ..................................................................... 135 Industrial bonanza: cluster of businesses ............................................... 135 Booming markets ....................................................................................... 140 Early electric systems ................................................................................ 142 The era of power ............................................................................... 143 Mobile applications of DC motors ......................................................... 144 Stationary applications of DC motors .................................................... 153 The invention of the electric induction motor ............................... 159 Alternating current: electromagnetic components .............................. 162 From induction coil to three-phase transformer .................................. 162 Alternating current: the induction motor ........................................... 166 Science and engineering discover induction .......................................... 166 Early induction motors ............................................................................. 169 The polyphase induction motor .............................................................. 172 Parallel development of the AC generator .......................................... 184 Later versions of induction motors ........................................................ 190 The invention of the AC induction motor ............................................ 193 A cluster of innovation for the AC induction motor........................... 197 The development of the electric alternating-current power system ..... 199 AC-distribution networks ......................................................................... 200 George Westinghouse (1846–1914) ........................................................ 206 Battle of currents: DC versus AC ....................................................... 217 Edison versus Westinghouse ................................................................... 218 ii The Invention of the Electro-motive Engine Conclusion ................................................................................... 227 Human curiosity, ingenuity, and competition ..................................... 228 Curiosity in the nature of lightning ......................................................... 228 Ingenuity ..................................................................................................... 230 Competition ................................................................................................ 231 Societal change induced by technical change ...................................... 232 Second Industrial Revolution: “Power to the people” ........................ 232 References .................................................................................... 239 About the author........................................................................... 253 iii B.J.G. van der Kooij iv Preface When everything is said and done, and all our breath is gone, The only thing that stays Is history, to guide our future ways. My lifelong intellectual fascination with technical innovation within the context of society started in Delft, the Netherlands, in the 1970s at the University of Technology—at both the electrical engineering school and the business school.1 Having been educated as a technical student with vacuum tubes, followed by transistors, I found the change and novelty of the new technology of microelectronics to be mind-boggling—not so much from a technical point of view but because of all the opportunities for new products, new markets, and new organizations, with a potent technology as the driving force. During my studies at both the School of Electric Engineering and the School of Business Administration,2 I was lucky enough to spend some time in Japan and California, where I observed how cultures influence the context for technology-induced change and what is considered novel. In Japan I explored the research environment; in Silicon Valley I saw the business environment—from the nuances of the human interaction of the Japanese, to the stimulating and raw capitalism of the United States. The technology forecast of my engineering thesis made the coming technology push a little clearer: the personal computer was on the horizon. The implementation of innovation in small and medium enterprises, the subject of my management thesis, left me with a lot of questions. Could something like a Digital Delta be created in the Netherlands? During the journey of my life, innovation has been the theme. For example, in the mid-1970s, I joined a mature electric company that 1 At present the schools referred to are called the Electrical Engineering School at the Delft University of Technology and the School of International Business Administration at the Erasmus University Rotterdam. 2 The institutions’ actual names were Afdeling Electro-techniek, Vakgroep Mikro- Electronica,
Load more

Recommended publications
  • Sparks, Shocks and Voltage Traces As Windows Into Experience: the Spiraled Conductor and Star Wheel Interrupter of Charles Grafton Page
    | Sparks, Shocks and Voltage Traces as Windows into Experience | 123 | Sparks, Shocks and Voltage Traces as Windows into Experience: The Spiraled Conductor and Star Wheel Interrupter of Charles Grafton Page Elizabeth CAVICCHI a T Abstract When battery current flowing in his homemade spiraled conductor switched off, nineteenth century experimenter Charles Grafton Page saw sparks and felt shocks, even in parts of the spiral where no current passed. Reproducing his experiment today is improvisational: an oscilloscope replaces Page’s body; a copper star spinning through galinstan substitutes for Barlow’s wheel interrupter. Green and purple flashes accompanied my spinning wheel. Unlike what Page’s shocks showed, induced voltages probed across my spiral’s wider spans were variable, precipitating extensive explorations of its resonant fre - quencies. Redoing historical experiments extends our experience, fostering new observations about natural phenomena and experimental development. Keywords: electromagnetic induction, historical replication, Charles Grafton Page, exploratory learning, spiral, Barlow wheel, galinstan, autotransformer T Introduction real? Facing wires and wiggling magnetic needles firsthand, while trying to make sense of it, deepens Historical experiments come to us in fragments: our perspective; we become confused and curious handwritten data, published reports, and often non - (Cavicchi 2003). Redoing an experiment is not just a functioning apparatus. A further carry-over may per - check on facts, dates, whether Oersted’s needle went sist in ideas, procedures, materials and inventions east or west. It gives us access to experience congru - bearing imprints of the prior work. All these are clues ous with the past: “’to know an experimenter, you to something both more transitory and more coher - should replicate her study’” (Kurz 2001, p.
    [Show full text]
  • Sir William Thomson, Baron Kelvin of Largs and the Institution of Engineering and Technology
    Chapter 6 Sir William Thomson, Baron Kelvin of Largs and the Institution of Engineering and Technology S. Hale Institution of Engineering and Technology, United Kingdom. Abstract Sir William Thomson, Baron Kelvin of Largs, was a member of the Society of Telegraph Engineers and the Institution of Electrical Engineers (the precursors of the current Institu- tion of Engineering and Technology) for 36 years. Elected as the President three times, Lord Kelvin’s involvement with the institution has had a lasting effect on the Institution of Engineering and Technology (IET). His bust (Fig. 1) is displayed at the IET’s London head- quarters at Savoy Place and his portrait hangs in the lecture theatre alongside those of other engineering luminaries such as Alessandro Volta and Michael Faraday. Every year, the IET also hosts a lecture in memory of Kelvin. This chapter will explore the background to the IET, the history of Kelvin’s relationship with the Institution and the impact that he had upon the Institution as a whole. 1 Introduction The history of the IET dates back to the late nineteenth century. It was founded on 17 May 1871 as the Society of Telegraph Engineers (STE), in response to the rapid development of a new communications technology, electrical telegraphy. 1.1 Early days of telegraphy Before the advent of electrical telegraphy, transmitting communications over long distances without the use of written correspondence relied on visual aids such as fire beacons, smoke signals and flags, and later, mechanised systems such as the semaphore system created by Claude Chappé in 1793 [1]. The idea of using electricity to send messages was first proposed in the 1750s [2] but it was not until the beginning of the nineteenth century that experiments began in earnest.
    [Show full text]
  • Bull. Hist. Chem. 11
    Bull. is. Cem. 11 ( 79 In consequence of this decision, many of the references in the index to volumes 1-20, 1816-26, of the Quarterly Journal of interleaved copy bear no correspondence to anything in the text Science and the Arts, published in 1826, in the possession of of the revised editions, the Royal Institution, has added in manuscript on its title-page Yet Faraday continued to add references between the dates "Made by M. Faraday", Since the cumulative index was of the second and third editions, that is, between 1830 and largely drawn from the separate indexes of each volume, it is 1842, One of these is in Section XIX, "Bending, Bowing and likely that the recurrent task of making those was also under- Cutting of Glass", which begins on page 522. It is listed as taken by Faraday. If such were indeed the case, he would have "Grinding of Glass" and refers to Silliman's Journal, XVII, had considerable experience in that kind of harmless drudgery, page 345, The reference is to a paper by Elisha Mitchell, dating from the days when his position at the Royal Institution Professor of Chemistry, Mineralogy, &c. at the University of was still that of an assistant to William Brande. Carolina, entitled "On a Substitute for WeIdler's Tube of Safety, with Notices of Other Subjects" (11). This paper is frn nd t interesting as it contains a reference to Chemical Manipulation and a practical suggestion on how to cut glass with a hot iron . M. aaay, Chl Mnpltn n Intrtn t (11): Stdnt n Chtr, n th Mthd f rfrn Exprnt f ntrtn r f rh, th Ar nd S, iis, M.
    [Show full text]
  • The Great Divergence the Princeton Economic History
    THE GREAT DIVERGENCE THE PRINCETON ECONOMIC HISTORY OF THE WESTERN WORLD Joel Mokyr, Editor Growth in a Traditional Society: The French Countryside, 1450–1815, by Philip T. Hoffman The Vanishing Irish: Households, Migration, and the Rural Economy in Ireland, 1850–1914, by Timothy W. Guinnane Black ’47 and Beyond: The Great Irish Famine in History, Economy, and Memory, by Cormac k Gráda The Great Divergence: China, Europe, and the Making of the Modern World Economy, by Kenneth Pomeranz THE GREAT DIVERGENCE CHINA, EUROPE, AND THE MAKING OF THE MODERN WORLD ECONOMY Kenneth Pomeranz PRINCETON UNIVERSITY PRESS PRINCETON AND OXFORD COPYRIGHT 2000 BY PRINCETON UNIVERSITY PRESS PUBLISHED BY PRINCETON UNIVERSITY PRESS, 41 WILLIAM STREET, PRINCETON, NEW JERSEY 08540 IN THE UNITED KINGDOM: PRINCETON UNIVERSITY PRESS, 3 MARKET PLACE, WOODSTOCK, OXFORDSHIRE OX20 1SY ALL RIGHTS RESERVED LIBRARY OF CONGRESS CATALOGING-IN-PUBLICATION DATA POMERANZ, KENNETH THE GREAT DIVERGENCE : CHINA, EUROPE, AND THE MAKING OF THE MODERN WORLD ECONOMY / KENNETH POMERANZ. P. CM. — (THE PRINCETON ECONOMIC HISTORY OF THE WESTERN WORLD) INCLUDES BIBLIOGRAPHICAL REFERENCES AND INDEX. ISBN 0-691-00543-5 (CL : ALK. PAPER) 1. EUROPE—ECONOMIC CONDITIONS—18TH CENTURY. 2. EUROPE—ECONOMIC CONDITIONS—19TH CENTURY. 3. CHINA— ECONOMIC CONDITIONS—1644–1912. 4. ECONOMIC DEVELOPMENT—HISTORY. 5. COMPARATIVE ECONOMICS. I. TITLE. II. SERIES. HC240.P5965 2000 337—DC21 99-27681 THIS BOOK HAS BEEN COMPOSED IN TIMES ROMAN THE PAPER USED IN THIS PUBLICATION MEETS THE MINIMUM REQUIREMENTS OF ANSI/NISO Z39.48-1992 (R1997) (PERMANENCE OF PAPER) WWW.PUP.PRINCETON.EDU PRINTED IN THE UNITED STATES OF AMERICA 3579108642 Disclaimer: Some images in the original version of this book are not available for inclusion in the eBook.
    [Show full text]
  • Valentine from a Telegraph Clerk to a Telegraph Clerk
    Science Museum Group Journal Technologies of Romance: Valentine from a Telegraph Clerk ♂ to a Telegraph Clerk ♀: the material culture and standards of early electrical telegraphy Journal ISSN number: 2054-5770 This article was written by Elizabeth Bruton 10-08-2019 Cite as 10.15180; 191201 Discussion Technologies of Romance: Valentine from a Telegraph Clerk ♂ to a Telegraph Clerk ♀: the material culture and standards of early electrical telegraphy Published in Autumn 2019, Issue 12 Article DOI: http://dx.doi.org/10.15180/191201 Keywords electrical telegraphy, poetry, scientific instruments, James Clerk Maxwell Valentine from A Telegraph Clerk ♂ to a Telegraph Clerk ♀, by JC Maxwell, 1860 The tendrils of my soul are twined With thine, though many a mile apart. And thine in close coiled circuits wind Around the needle of my heart. Constant as Daniell, strong as Grove. Ebullient throughout its depths like Smee, My heart puts forth its tide of love, And all its circuits close in thee. O tell me, when along the line From my full heart the message flows, What currents are induced in thine? One click from thee will end my woes. Through many an Ohm the Weber flew, And clicked this answer back to me; I am thy Farad staunch and true, Charged to a Volt with love for thee Component DOI: http://dx.doi.org/10.15180/191201/001 Introduction In 1860, renowned natural philosopher (now referred to as a ‘scientist’ or, more specifically in the case of Clerk Maxwell, a ‘physicist’) James Clerk Maxwell wrote ‘Valentine from a Telegraph Clerk ♂ [male] to a Telegraph Clerk ♀ [female]’ (Harman, 2001).[1] The short poem was a slightly tongue-in-cheek ode to the romance of the electric telegraph littered with references to manufacturers of batteries used in electrical telegraphy around this time such as John Daniell, Alfred Smee, and William Grove and electrical units (now SI derived units) such as Ohm, Weber, Farad and Volt (Mills, 1995).
    [Show full text]
  • Coversheet for Thesis in Sussex Research Online
    A University of Sussex DPhil thesis Available online via Sussex Research Online: http://sro.sussex.ac.uk/ This thesis is protected by copyright which belongs to the author. This thesis cannot be reproduced or quoted extensively from without first obtaining permission in writing from the Author The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the Author When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given Please visit Sussex Research Online for more information and further details Elkington & Co. and the Art of Electro-Metallurgy, circa 1840-1900. Alistair Grant. A Thesis Submitted to the University of Sussex for Examination for the Degree of Doctor of Philosophy. September 2014. 2 I hereby declare that this thesis is solely my own work, and has not been, and will not be submitted in whole, or in part, to another University for the award of any other degree. Signature:……………………………………… 3 This PhD thesis is dedicated to my wife Lucy and my daughter Agnes. I would like to thank my wife, Dr. Lucy Grant, without whose love, encouragement, and financial support my doctoral studies could not have happened. Her fortitude, especially during the difficult early months of 2013 when our daughter Agnes was ill, anchored our family and home, and enabled me to continue my research and complete this PhD thesis. 4 ACKNOWLEDGEMENTS First and foremost, I would like to thank my supervisor Professor Maurice Howard. Having nurtured my enthusiasm for Art History as an undergraduate at the University of Sussex from 1983-1986, when I approached him, 23 years later, about pursuing PhD research into Elkington & Co.
    [Show full text]
  • L. Observations on Some Peculiar Properties Acquired by Plates of Platina, Which Have Been Used As the Electrodes of a Voltaic Battery
    Philosophical Magazine Series 3 ISSN: 1941-5966 (Print) 1941-5974 (Online) Journal homepage: http://www.tandfonline.com/loi/tphm14 L. Observations on some peculiar properties acquired by plates of platina, which have been used as the electrodes of a voltaic battery Golding Bird M.D. F.L.S. F.G.S. To cite this article: Golding Bird M.D. F.L.S. F.G.S. (1838) L. Observations on some peculiar properties acquired by plates of platina, which have been used as the electrodes of a voltaic battery , Philosophical Magazine Series 3, 13:83, 379-386, DOI: 10.1080/14786443808649597 To link to this article: http://dx.doi.org/10.1080/14786443808649597 Published online: 01 Jun 2009. Submit your article to this journal Article views: 3 View related articles Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=3phm20 Download by: [University of California, San Diego] Date: 26 June 2016, At: 07:29 Dr. {3. Bird on certain Properties of Platina Electrodes. 379 tive or negative divergence. The discharge took place in both my cases on a leaf of writing paper moistened with distilled water, which was applied to the inferior plate of the condenser, while another leaf of moist paper covering the upper plate was touched with the fingers in order to make everything alike on both sides with respect to the condenser. The most simple form of the experiment might however be this; that a zinc condenser plate should be immediately touched with the moist fingers, which, as others have already observed, is sufficient to produce a negative shock.
    [Show full text]
  • Puck.Js Realvnc and Raspberry Pi Research Skills
    The RingTHE JOURNAL OF T HE CAMBRIDGE COMPU T ER LAB RING Issue XLIV— January 2017 Who’s who 6 Puck.js 2 Another Kickstarter success for Hall of Fame news 8 Espruino Computer Laboratory news 11 RealVNC and Raspberry Pi 5 A shared passion Research Skills 9 Programming matter www.cl.cam.ac.uk/ring 2 HALL OF FAME PROFILE Puck.js Gordon Williams started the Espruino project in 2012. Puck.js is the third successful Espruino Kickstarter and, since Christmas, over 20,000 devices have been shipped worldwide. First it was Espruino, the first Java Script microcontroller. Then came However there are many other uses for beacons such as coarse Espruino Pico which allows you to control electronics quickly and positioning (of a user relative to beacons, or of beacons relative to easily with a tiny USB stick that runs JavaScript. Gordon Williams’s receivers). Their low price (sometimes less than $5 each, including latest Kickstarter project is Puck.js, an open source JavaScript micro- case and battery), makes them extremely attractive. controller that you can program wirelessly. TR: Puck.js is a Bluetooth low energy (BLE) beacon. What is special about it? TR: Can you explain what Bluetooth LE is, and why it’s interesting? GW: Puck.js can be a BLE beacon, but it’s a lot more than that. It GW: Bluetooth LE (Bluetooth Low Energy or Bluetooth Smart) is contains a button, temperature and light sensors, a magnetometer, IR a 2.4Ghz radio standard originally created by Nokia. Unlike normal transmitter, and a full Bluetooth LE implementation (both a master Bluetooth it’s designed for low power and cost rather than high band- and slave) along with the Espruino JavaScript interpreter (software width.
    [Show full text]
  • The Electric Telegraph
    To Mark, Karen and Paul CONTENTS page ORIGINS AND DEVELOPMENTS TO 1837 13 Early experiments—Francis Ronalds—Cooke and Wheatstone—successful experiment on the London & Birmingham Railway 2 `THE CORDS THAT HUNG TAWELL' 29 Use on the Great Western and Blackwall railways—the Tawell murder—incorporation of the Electric Tele- graph Company—end of the pioneering stage 3 DEVELOPMENT UNDER THE COMPANIES 46 Early difficulties—rivalry between the Electric and the Magnetic—the telegraph in London—the overhouse system—private telegraphs and the press 4 AN ANALYSIS OF THE TELEGRAPH INDUSTRY TO 1868 73 The inland network—sources of capital—the railway interest—analysis of shareholdings—instruments- working expenses—employment of women—risks of submarine telegraphy—investment rating 5 ACHIEVEMENT IN SUBMARINE TELEGRAPHY I o The first cross-Channel links—the Atlantic cable— links with India—submarine cable maintenance com- panies 6 THE CASE FOR PUBLIC ENTERPRISE 119 Background to the nationalisation debate—public attitudes—the Edinburgh Chamber of Commerce— Frank Ives. Scudamore reports—comparison with continental telegraph systems 7 NATIONALISATION 1868 138 Background to the Telegraph Bill 1868—tactics of the 7 8 CONTENTS Page companies—attitudes of the press—the political situa- tion—the Select Committee of 1868—agreement with the companies 8 THE TELEGRAPH ACTS 154 Terms granted to the telegraph and railway companies under the 1868 Act—implications of the 1869 telegraph monopoly 9 THE POST OFFICE TELEGRAPH 176 The period 87o-1914—reorganisation of the
    [Show full text]
  • A Chronological History of Electrical Development from 600 B.C
    From the collection of the n z m o PreTinger JJibrary San Francisco, California 2006 / A CHRONOLOGICAL HISTORY OF ELECTRICAL DEVELOPMENT FROM 600 B.C. PRICE $2.00 NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION 155 EAST 44th STREET NEW YORK 17, N. Y. Copyright 1946 National Electrical Manufacturers Association Printed in U. S. A. Excerpts from this book may be used without permission PREFACE presenting this Electrical Chronology, the National Elec- JNtrical Manufacturers Association, which has undertaken its compilation, has exercised all possible care in obtaining the data included. Basic sources of information have been search- ed; where possible, those in a position to know have been con- sulted; the works of others, who had a part in developments referred to in this Chronology, and who are now deceased, have been examined. There may be some discrepancies as to dates and data because it has been impossible to obtain unchallenged record of the per- son to whom should go the credit. In cases where there are several claimants every effort has been made to list all of them. The National Electrical Manufacturers Association accepts no responsibility as being a party to supporting the claims of any person, persons or organizations who may disagree with any of the dates, data or any other information forming a part of the Chronology, and leaves it to the reader to decide for him- self on those matters which may be controversial. No compilation of this kind is ever entirely complete or final and is always subject to revisions and additions. It should be understood that the Chronology consists only of basic data from which have stemmed many other electrical developments and uses.
    [Show full text]
  • Axial-Flux Permanent-Magnet Dual-Rotor Generator for a Counter-Rotating Wind Turbine
    energies Article Axial-Flux Permanent-Magnet Dual-Rotor Generator for a Counter-Rotating Wind Turbine Filip Kutt *,† , Krzysztof Blecharz † and Dariusz Karkosi ´nski † Faculty of Electrical and Control Engineering, Gda´nskUniversity of Technology, 80-233 Gda´nsk,Poland; [email protected] (K.B.); [email protected] (D.K.) * Correspondence: fi[email protected]; Tel.: +48-58-347-19-39 † These authors contributed equally to this work. Received: 31 March 2020; Accepted: 26 May 2020; Published: 2 June 2020 Abstract: Coaxial counter-rotating propellers have been widely applied in ships and helicopters for improving the propulsion efficiency and offsetting system reactive torques. Lately, the counter-rotating concept has been introduced into the wind turbine design. Distributed wind power generation systems often require a novel approach in generator design. In this paper, prototype development of axial-flux generator with a counter-rotating field and armature is presented. The design process was composed of three main steps: analytical calculation, FEM simulation and prototype experimental measurements. The key aspect in the prototype development was the mechanical construction of two rotating components of the generator. Sturdy construction was achieved using two points of contact between both rotors via the placement of the bearing between the inner and outer rotor. The experimental analysis of the prototype generator has been conducted in the laboratory at the dynamometer test stand equipped with a torque sensor. The general premise for the development of such a machine was an investigation into the possibility of developing a dual rotor wind turbine. The proposed solution had to meet certain criteria such as relatively simple construction of the generator and the direct coupling between the generator and the wind turbines.
    [Show full text]
  • 2016-09-27-2-Generator-Basics
    Generator Basics Basic Power Generation • Generator Arrangement • Main Components • Circuit – Generator with a PMG – Generator without a PMG – Brush type –AREP •PMG Rotor • Exciter Stator • Exciter Rotor • Main Rotor • Main Stator • Laminations • VPI Generator Arrangement • Most modern, larger generators have a stationary armature (stator) with a rotating current-carrying conductor (rotor or revolving field). Armature coils Revolving field coils Main Electrical Components: Cutaway Main Electrical Components: Diagram Circuit: Generator with a PMG • As the PMG rotor rotates, it produces AC voltage in the PMG stator. • The regulator rectifies this voltage and applies DC to the exciter stator. • A three-phase AC voltage appears at the exciter rotor and is in turn rectified by the rotating rectifiers. • The DC voltage appears in the main revolving field and induces a higher AC voltage in the main stator. • This voltage is sensed by the regulator, compared to a reference level, and output voltage is adjusted accordingly. Circuit: Generator without a PMG • As the revolving field rotates, residual magnetism in it produces a small ac voltage in the main stator. • The regulator rectifies this voltage and applies dc to the exciter stator. • A three-phase AC voltage appears at the exciter rotor and is in turn rectified by the rotating rectifiers. • The magnetic field from the rotor induces a higher voltage in the main stator. • This voltage is sensed by the regulator, compared to a reference level, and output voltage is adjusted accordingly. Circuit: Brush Type (Static) • DC voltage is fed External Stator (armature) directly to the main Source revolving field through slip rings.
    [Show full text]