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Income? Bisone
INCOME? BISONE ED 179 392 SP 029 296 $ AUTHOR Hamilton, Howard B. TITLE Problem Manual for Power Processiug, Tart 1. Electric Machinery Analysis. ) ,INSTITUTION Pittsbutgh Univ., VA. 51'014 AGENCY National Science Foundation, Weeshingtcni D.C. PUB DATE -70 GRANT NSF-GY-4138 NOTE 40p.; For_related documents', see SE 029 295-298 EDRS PRICE MF01/BCO2 Plus Postage. DESCRIPTORS *College Science: Curriculum Develoimeft: Electricity: Electromechanical lacshnology;- Electfonics: *Engineering Educatiob: Higher Education: Instructional Materials: *Problem Solving; Science CourAes:,'Science Curriculum: Science . Eductttion; *Science Materials: Scientific Concepts AOSTRACT This publication was developed as aPortion/ofa . two-semester se4uence commencing t either the-sixth cr seVenth.term of the undergraduate program in electrical engineering at the University of Pittsburgh. The materials of tfie two courses, produced by' National Science Foundation grant, are concernedwitli power con ion systems comprising power electronic devices, electromechanical energy converters, and,associnted logic configurations necessary to cause the systlp to behave in a, prescrib,ed fashion. The erphasis in this portion of the'two course E` sequende (Part 1)is on electric machinery analysis.. 7his publication is-the problem manual for Part 1, which provide's problems included in 4, the first course. (HM) 4 Reproductions supplied by EDPS are the best that can be made from the original document. * **************************v******************************************** 2 -
Transient Analysis of Three-Phase Wound Rotor (Slip-Ring) Induction Motor Under Operating Condition
International Journal of Recent Engineering Research and Development (IJRERD) ISSN: 2455-8761 www.ijrerd.com || Volume 02 – Issue 07 || July 2017 || PP. 19-32 Transient Analysis of Three-Phase Wound Rotor (Slip-Ring) Induction Motor under Operating Condition Obute K.C.1, Enemuoh F.O.1 1 – Department of Electrical Engineering Nnamdi Azikiwe University Awka, Anambra State Nigeria Corresponding Author - Obute Kingsley Chibueze Department of Electrical Engineering Nnamdi Azikiwe University Awka, Anambra State Nigeria Abstract: This work investigates the transient behaviours of a three phase wound rotor type induction motor, running on load. When starting a motor under load condition becomes paramount, obviously a wound rotor (slip ring) induction becomes the best choice of A.C. motor. This is because maximum torque at starting can be achieved by adding external resistance to the rotor circuit through slip-rings. Normally a face-plate type starter is used, and as the resistance is gradually reduced, the motor characteristics at each stage changes from the other (John Bird 2010). Hence, the three phase wound rotor (slip ring) induction motor competes favourably with the squirrel cage induction motor counterpart as the most widely used three-phase induction motor for industrial applications. The world-wide popularity and availability of this motor type has attracted a deep – look and in-depth research including its transient behavior under plugging (operating) condition. This paper unveils, through mathematical modeling, followed by dynamic simulation, the transient performance of this peculiar machine, analyzed based on Park’s transformation technique. That is with direct-quadrature-zero (d-q-o) axis based modeling in stationary reference frame. -
Electrical Machines
1 Electrical Machines 1. The left hand rule is applicable to (a) generator ( b) motor (c) transformer ( d) ( a) and ( b) both (e) ( a) or ( b) 2. The eddy current losses in the transformer will be reduced if (a) the laminations are thick (b) number of turns in the primary winding is reduced (c) the number of turns in the secondary winding is reduced (d) the laminations are thin 3. The speed of d.c. series motor at no load is (a) zero ( b) 1500 r.p.m. (c) infinity ( d) 3000 r.p.m. (e) none of the above 4. A sinusoidal voltage of frequency 1 Hz is applied to the field of d.c. generator. The armature voltage will be (a) 1 Hz square wave ( b) 1 Hz sinusoidal voltage (c) d.c. voltage ( d) none of the above 5. The function of the commutator in a d.c. machine is (a) to change alternating current to a direct current (b) to improve commutation (c) for easy control (d) to change alternating voltage to direct voltage 6. The phase sequence of voltage generated in the alternator can be reversed by reversing its field current. (a) true ( b) false 7. The rotation of three phase induction motor can be reversed by interchanging any two of the supply phases. (a) true ( b) false 2 ELECTRICAL ENGINEERING 8. The starting torque of the three phase induction motor can be increased by (a) increasing the rotor reactance (b) increasing the rotor resistance (c) increasing the stator resistance (d) none of the above 9. -
NNNNN May 19, 1970 A
May 19, 1970 A. D. APPLETON 3,513,340 HOMOPOLAR ELLCTRIC MACHINES Filed Jan. 6, 1967 2 Sheets-Sheet l -uo Lo NNNNN May 19, 1970 A. D. APPLETON HOMOPOLAR ELECTRIC MACHINES 3,513,340 Filed Jan. 6, 1967 2 Sheets-Sheet 2 222a1a1a2.1274.1444/4/14/a/ 244. A. ZZ 3,513,340 United States Patent Office Patented May 19, 1970 2 3,513,340 FIG. 1 shows diagrammatically a homopolar electrical HOMOPOLAR ELECTRIC MACHINES machine in accordance with the invention for use as a low Anthony Derek Appleton, Newcastle upon Tyne, Eng speed motor, land, assignor to International Research & Develop FIG. 2 is a longitudinal section of a typical machine of Company Limited, Newcastle upon Tyne, Eng the general form illustrated in FIG. 1, and FIG. 3 is a Filed Jan. 6, 1967, Ser. No. 607,784 detail of FIG. 2 on an enlarged scale. Claims priority, application Great Britain, Jan. 12, 1966, The homopolar machine shown in FIG. 1 comprises 1,530/66 two rotors 1 and 2. Int. Cl. H02k 31/00, 47/14 Each rotor is in the from of a disc of electrically con U.S. C. 310-13 10 Claims ducting material Such as copper. The copper discs may O each be mounted on a supporting disc of non-electrically conducting material. ABSTRACT OF THE DISCLOSURE Each rotor rotates within a magnetic field common to A homopolar machine is disclosed having two rotors both rotors and provided by a single superconducting coil in a common magnetic field, preferably provided by a 3, which surrounds the rotors. -
Serial Step up Resonant Frequency Static Discharge System - Tesla Gun
International Journal of Pure and Applied Mathematics Volume 114 No. 7 2017, 531-546 ISSN: 1311-8080 (printed version); ISSN: 1314-3395 (on-line version) url: http://www.ijpam.eu Special Issue ijpam.eu Serial Step Up Resonant Frequency Static Discharge System - Tesla Gun R. Ramya1, Abhinash Kumar Patra2, Saurodeep Adhikary3, Rishav Ranjan Paul4 SRM University, Kattankulathur [email protected] and [email protected] Abstract Currently weapons research and development takes up the greatest share of any defense budget. In this aspect, India is lagging, mostly due to economical and institutional constraints. It is the largest importer of arms and ammunitions in the world. However, there is still a need for a failsafe defense system. This paper is a step towards addressing this shortcoming of the Indian military. However, this is not the first prototypal weapons system in the world. The U.S. Defense Strategic Defense Initiative put into development the technology of a similar type using a particle beam to be used as a weapon in outer space as part of the Beam Experiments Aboard Rocket (BEAR) project. This is the next step to build a weapon system that rises above ammunition constraint and environmental hazard. The basic premise of a Tesla Gun involves static discharge at a very high voltage. There are three main elements of the system. The first is the voltage step up. The next is the resonant circuit and the final element is the targeting system. Key Words and Phrases: Tesla Coil, Static Discharge, Resonant Frequency, Bounces. 1. Introduction 1 531 International Journal of Pure and Applied Mathematics Special Issue A Tesla coil is a device producing a high frequency current, at a very high voltage but of relatively small intensity. -
A Comparative Study of Methods for Calculating AC Winding Losses in Permanent Magnet Machines
A Comparative Study of Methods for Calculating AC Winding Losses in Permanent Magnet Machines Narges Taran Vandana Rallabandi Dan M. Ionel SPARK Lab, ECE Dept. SPARK Lab, ECE Dept. SPARK Lab, ECE Dept. University of Kentucky University of Kentucky University of Kentucky Lexington, KY, USA Lexington, KY, USA Lexington, KY, USA [email protected] [email protected] [email protected] Greg Heins Dean Patterson Regal Beloit Corp. Regal Beloit Corp. Research and Development Research and Development Rowville, VIC, Australia Rowville, VIC, Australia [email protected] [email protected] Abstract—In this study different methods of estimating the are discussed. The additional conductor loss caused by rotor additional ac winding loss due to eddy currents at open-circuit PMs is more significant in case of open slot machines, due are explored. A comparative study of 2D and 3D FEA, and to the increased leakage flux, and an extreme case occurs for hybrid numerical and analytical methods is performed in order to recommend feasible approaches to be employed. Axial flux air cored machines where the stator core is eliminated and all permanent magnet (AFPM) machine case studies are included, conductors are exposed to the air gap flux density. namely a machine with open slots and a coreless configuration. Several authors have analytically estimated the additional These machine topologies are expected to present a substantial amount of ac winding loss, which would therefore need to ac copper loss [1], [4]–[8]. Two–dimensional FEA is used be considered during optimal design. This study is one of in many studies [9]–[12] while 3D FEA has been employed the first ones to compare meticulous 3D FEA models with only very recently in few works [3], [13]. -
Modelling of Iron Losses of Permanent Magnet Synchronous Motors
MODELLING OF IRON LOSSES OF PERMANENT MAGNET SYNCHRONOUS MOTORS Chunting Mi A thesis submitted in confollILity with the requirements for the Degree of Doctor of Philosophy in the Department of EIectncal and Computer Engineering University of Toronto O Copyright by Chunting Mi, 200 1 The author has pteda non- L'auteur a accordé une Licence non exclusive licence dowing the exclusive permettant à la National Li* of Canada to Bibliothèque nationde du Canada de reproduce, Ioan, distnbute or sell reproduire, prêter, distriilmer ou copies of this thesis in microform, vendre des copies de cette thèse sous paper or eIectronic formats. la forme de microfiche/film, de reproduction sur papier ou sur format electronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qai protège cette thèse. thesis nor substantial extracts fiom it Ni la thèse ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent être imprimés reprodnced without the author's ou autrement reproduits sans son pdssi01l. autorisation. MODELLING OF IRûN LOSSES OF PERMANENT MAGNET SYNCHRONOUS MOTORS Chunting Mi A thesis submitted in conformity with the requUements for the De- of Doctor of Philosophy in the Department of Electrical and Computer Engineering University of Toronto @ Copyright by Chunting Mi, 200 1 ABSTRACT This thesis proposes a refïned approach to evaluate iron losses of surface-mounted permanent magnet (PM) synchronous motors. PM synchronous moton have higher efficiency than induction machines with the same &me and same power ratnigs. However, in PM synchronous motors, iron Iosses form a larger portion of the total losses than in induction machines. -
RESISTANCE of COIL 1 Temperature Effects
Chapter 6—Resistance of Coil 6–1 RESISTANCE OF COIL The resistance RTC in the RLC model is an effective or equivalent resistance which rep- resents all the losses in the Tesla coil. It includes 1. Ohmic or copper losses 2. Dielectric losses, coil form and conductor insulation 3. Eddy current losses in toroid, strike ring, and soil 4. Radiation losses 5. Losses in the spark It is surprising how difficult it is to calculate these various losses. Making meaningful measurements can also be challenging. If we operate at low input voltage so we are below spark breakout, then we can ignore the last term for the moment. I will ramble through some considerations for the other losses. 1 Temperature Effects Almost all coils are wound with copper wire. It is moderately priced and widely available. There might be an occasional aluminum coil, usually from some ‘bargain’ at a surplus auction. Aluminum has higher resistivity than copper, so to get a given resistance the wire must be physically larger. We saw earlier that to get a high toroid voltage we needed a coil with large L and/or small R. If we use larger wire to keep the resistance the same, the coil must be physically larger and the inductance will decrease. We would expect therefore that aluminum coils would always be inferior to copper coils. Example You are given a choice between two spools of magnet wire, each 1000 feet in length. The copper is 24 gauge, with nominal resistance 25.67 Ω, while the aluminum is 22 gauge, with nominal resistance 26.46 Ω. -
Matched Transformers for Synchro and Resolver Applications
Electrocomponent Science and Technology (C) Gordon and Breach Science Publishers Ltd. 1975, Vol. 2, pp. 121-134 Printed in Great Britain MATCHED TRANSFORMERS FOR SYNCHRO AND RESOLVER APPLICATIONS M. PRATT Professional Components Division, Ferranti Ltd., Dundee, UK (Received December 17; 1974; in final form March 3, 1975) Transformer pairs in Scott Tee and similar transformer arrangements have been used for some considerable time in precision synchro/resolver angular measuring gear and in synchro to digital converters. Literature on the subject of transformer requirements is, however, scant or non-existent.I, 2 This paper describes the basic principle of transformer operation and develops a design approach which, although aimed primarily at the minimisation of transformer hardware size, still maintains the required level of angular accuracy. The method applies to transformers utilised in mobile systems, particularly transformer arrangements working under loaded conditions. INTRODUCTION manufacturing approach leading to minimised weight and volume, especially in transformers looking Synchro shaft angle to digital conversion techniques towards and positioning the synchro. (Digital to are used extensively in airborne and shipborne synchro mode application.) systems to give direct read-out positional data on synchro and resolver elements with an ability to 2 THREE TO FOUR WIRE CONVERSION reposition synchro devices from a central control computer. The use of transformers in three to four wire Shaft angle data, to and from the control point, is conversion is readily understood by first considering by a three wire system, usually with the synchro Figure 1. which is descriptive of a synchro element elements energised at a frequency of 400 Hz. -
Slip Ring Rotor - Vertical
Motors I Automation I Energy I Transmission & Distribution I Coatings Low and high voltage three phase induction motors M line - Slip ring rotor - Vertical Installation, Operation and Maintenance Manual Installation, Operation and Maintenance Manual Document Number: 11734748 Models: MAA, MAP, MAD, MAT, MAV, MAF, MAR, MAI, MAW and MAL Language: English Revision: 9 August 2018 Dear Customer, Thank you for purchasing a WEG motor. Our products are developed with the highest standards of quality and efficiency which ensures outstanding performance. Since electric motors play a major role in the comfort and well-being of mankind, it must be identified and treated as a driving machine with characteristics that involve specific care, such as proper storage, installation and maintenance All efforts have been made to ensure that the information contained in this manual is faithful to the configurations and applications of the motor. Therefore, we recommend that you read this manual carefully before proceeding with the installation, operation or maintenance of the motor in order to ensure safe and reliable operation of your equipment and facility. If you need any further information, please contact WEG. Always keep this manual close to the motor, so that it can be consulted whenever necessary. ATTENTION 1. It is imperative to follow the procedures contained in this manual for the warranty to be valid; 2. The motor installation, operation and maintenance procedures must be performed only by qualified personnel. NOTES 1. The total or partial reproduction of information supplied in this manual is authorized, provided that reference is made to its source. If this manual is lost, an electronic PDF file is available at www.weg.net or another printed copy may be requested. -
Abstract Transformer Design for Dual Active Bridge
ABSTRACT TRANSFORMER DESIGN FOR DUAL ACTIVE BRIDGE CONVERTER by Egor Iuravin Power transformers have a long history which takes root in 19th century when Michael Faraday introduced the definition of the electromagnetic induction. In the beginning of the 1960s, there was a tendency to increase the frequency of switch mode power supplies. This thesis provides the detailed summary of operating principles, design, simulation and experimental analysis of high frequency power transformers. The focus of this research is to find an optimal transform solution for the DAB converter operating at a power level of 2 kW. Furthermore, the investigation will be carried out to estimate and measure the contact loss of a transformer. TRANSFORMER DESIGN FOR DUAL ACTIVE BRIDGE CONVERTER A Thesis Submitted to the Faculty of Miami University in partial fulfillment of the requirements for the degree of Master of Science in Computational Science and Engineering by Egor Iuravin Miami University Oxford, Ohio 2018 Advisor: Dr. Mark J. Scott Reader: Dr. Haiwei Cai Reader: Dr. Dmitriy Garmatyuk ©2018 Egor Iuravin This Thesis titled TRANSFORMER DESIGN FOR DUAL ACTIVE BRIDGE CONVERTER by Egor Iuravin has been approved for publication by College of Engineering and Computing and Department of Electrical and Computer Engineering ____________________________________________________ Dr. Mark J Scott ______________________________________________________ Dr. Haiwei Cai _______________________________________________________ Dr. Dmitriy Garmatyuk Table of Contents 1. Introduction -
ELECTRICAL SCIENCE Module 10 AC Generators
DOE Fundamentals ELECTRICAL SCIENCE Module 10 AC Generators Electrical Science AC Generators TABLE OF CONTENTS Table of Co nte nts TABLE OF CONTENTS ................................................................................................... i LIST OF FIGURES ...........................................................................................................ii LIST OF TABLES ............................................................................................................ iii REFERENCES ................................................................................................................iv OBJECTIVES .................................................................................................................. v AC GENERATOR COMPONENTS ................................................................................. 1 Field ............................................................................................................................. 1 Armature ...................................................................................................................... 1 Prime Mover ................................................................................................................ 1 Rotor ............................................................................................................................ 1 Stator ........................................................................................................................... 2 Slip Rings ...................................................................................................................