Lecture Notes on Electrical Machines-Ii
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Single-Phase Line Start Permanent Magnet Synchronous Motor with Skewed Stator*
POWER ELECTRONICS AND DRIVES Vol. 1(36), No. 2, 2016 DOI: 10.5277/PED160212 SINGLE-PHASE LINE START PERMANENT MAGNET SYNCHRONOUS MOTOR WITH SKEWED STATOR* MACIEJ GWOŹDZIEWICZ, JAN ZAWILAK Wrocław University of Science and Technology, Wybrzeże Stanisława Wyspiańskiego 27, 50-370 Wrocław, Poland, e-mail: [email protected], [email protected] Abstract: The article deals with single-phase line start permanent magnet synchronous motor with skewed stator. Constructions of two physical motor models are presented. Results of the motors run- ning properties are analysed. Keywords: single-phase motor, permanent magnet, skew, vibration 1. INTRODUCTION Single-phase induction motors almost always have skewed rotors. It is a simple and effective solution in limitation of the motor vibration, noise and torque pulsation. In the case of line start permanent magnet synchronous motors skewed rotor is ex- tremely difficult to manufacture due to interior permanent magnets. Skewed stator is less complicated in comparison with skewed rotor [3], [4], [7], [8]. During many tests of single-phase line start permanent magnet synchronous motor physical models The authors noticed that vibration is one of the main drawbacks of these motors [1], [2]. It prompted them to construct and build a single-phase line start permanent magnet motor with skewed stator. 2. MOTOR CONSTRUCTION Two dimensional field-circuit models of the single-phase line start permanent magnet synchronous motor were applied in Maxwell software. The models are based on the mass production single-phase induction motor Seh 80-2B type: rated power Pn = 1.1 kW, rated voltage Un = 230 V, rated frequency fn = 50 Hz, number of pole * Manuscript received: September 7, 2016; accepted: December 7, 2016. -
IEEE/PES Transformers Committee Fall 2017 Meeting Minutes
Transformers Committee Chair: Stephen Antosz Vice Chair: Sue McNelly Secretary: Bruce Forsyth Treasurer: Greg Anderson Awards Chair/Past Chair: Don Platts Standards Coordinator: Jim Graham IEEE/PES Transformers Committee Fall 2017 Meeting Minutes Louisville, KY October 30 – November 2, 2017 Unapproved (These minutes are on the agenda to be approved at the next meeting in Spring 2018) TABLE OF CONTENTS GENERAL ADMINISTRATIVE ITEMS 1.0 Agenda 2.0 Attendance OPENING SESSION – MONDAY OCTOBER 30, 2017 3.0 Approval of Agenda and Previous Minutes – Stephen Antosz 4.0 Chair’s Remarks & Report – Stephen Antosz 5.0 Vice Chair’s Report – Susan McNelly 6.0 Secretary’s Report – Bruce Forsyth 7.0 Treasurer’s Report – Gregory Anderson 8.0 Awards Report – Don Platts 9.0 Administrative SC Meeting Report – Stephen Antosz 10.0 Standards Report – Jim Graham 11.0 Liaison Reports 11.1. CIGRE – Raj Ahuja 11.2. IEC TC14 – Phil Hopkinson 11.3. Standards Coordinating Committee, SCC No. 18 (NFPA/NEC) – David Brender 11.4. Standards Coordinating Committee, SCC No. 4 (Electrical Insulation) – Paulette Payne Powell 12.0 Hot Topics for the Upcoming – Subcommittee Chairs 13.0 Opening Session Adjournment CLOSING SESSION – THURSDAY NOVEMBER 2, 2017 14.0 Chair’s Remarks and Announcements – Stephen Antosz 15.0 Meetings Planning SC Minutes & Report – Gregory Anderson 16.0 Reports from Technical Subcommittees (decisions made during the week) 17.0 Report from Standards Subcommittee (issues from the week) 18.0 New Business 19.0 Closing Session Adjournment APPENDIXES – ADDITIONAL DOCUMENTATION Appendix 1 – Meeting Schedule Appendix 2 – Semi-Annual Standards Report Appendix 3 – IEC TC14 Liaison Report Appendix 4 – CIGRE Report Page 2 of 55 ANNEXES – UNAPPROVED MINUTES OF TECHNICAL SUBCOMMITTEES NOTE: The Annexes included in these minutes are unapproved by the respective subcommittees and are accurate as of the date the Transformers Committee meeting minutes were published. -
IEEE Grounding Transformers
Grounding Transformers John S. Levine, P.E. Levine Lectronics and Lectric, Inc. [email protected] 1 • It is used to provide a ground path on either an ungrounded Wye or a Delta connected system • The relatively low impedance path to ground maintains the system neutral at ground potential • On Ungrounded systems you can have overvoltages of 6 to 8 times normal with arcing faults Arcing Ground Faults Intermittent or Re-strike •Plot of transient over-voltage for an arcing ground fault Arcing Ground Faults Intermittent or Re-strike •Intermittent ground fault: A re-striking ground fault can create a high frequency oscillator (RLC circuit), independent of L and C values, causing high transient over- voltages. – i.e. re-striking due to ac voltage waveform or loose wire caused by vibration 480V Delta Source 3Ø Load Rfe V V Cb Cb S fa THE HIGH RESISTANCE GROUNDED POWER SYSTEM CONTROL OF TRANSIENT OVERVOLTAGE • It supports the voltage on a faulted phase – If a single line-to-ground fault occurs on an ungrounded or isolated system, no return path exists and no current flows – The system will continue to operate but the other two un- faulted lines will rise in in voltage by the square root of 3, possibly overstressing the transformer insulation, and other components, by 173% UNGROUNDED SYSTEM NORMAL CONDITIONS UNGROUNDED SYSTEM GROUND FAULT ON PHASE A • Provides a metering point to measure faults A typical example is a Wind Farm. They utilize grounding transformers for fault protection on ungrounded lines When a ground fault occurs on a collector cable causes the substation circuit breaker to open, the wind turbine string becomes isolated Turbines do not always detect the fault and the generators continue to energize the cable. -
Chapter # 2 Cylindrical Synchronous Generator and Motor 1
Benha University Electrical Engineering Department Faculty of Engineering at Shubra Electric Machines II Chapter # 2 Cylindrical Synchronous Generator and Motor 1. Introduction Synchronous machines are named by this name as their speed is directly related to the line frequency. Synchronous machines may be operated either as motor or generator. Synchronous generators are called alternators. Synchronous motors are used mainly for power factor correction when operate at no load. Synchronous machines are usually constructed with stationary stator (armature) windings that carrying the current and rotating rotor (field) winding that create the magnetic flux. This flux is produced by DC current from a separate source (e.g. DC shunt generator). 2. Types of Synchronous Generators The type of synchronous generators depends on the prime mover type as: a) Steam turbines: synchronous generators that driven by steam turbine are high speed machines and known as turbo alternators. The maximum rotor speed is 3600 rpm corresponding 60 Hz and two poles. b) Hydraulic turbines: synchronous generators that driven by water turbine are with speed varies from 50 to 500 rpm. The type of turbine to be used depends on the water head. For water head of 400m, Pelton wheel turbines are used. But for water head up to 350 m, Francis Turbines are used. For water head up to 50 m, Kaplan Turbines are used. 1 Chapter #2 Cylindrical Synchronous Machines Dr. Ahmed Mustafa Hussein Benha University Electrical Engineering Department Faculty of Engineering at Shubra Electric Machines II c) Diesel Engines: they are used as prime movers for synchronous generator of small ratings. For the type a) and c) the rotor shape is cylindrical as shown in Fig. -
Neutral Current Problem and Mitigation Techniques: an Overview
IOSR Journal of Engineering (IOSR JEN) www.iosrjen.org ISSN (e): 2250-3021, ISSN (p): 2278-8719 PP 62-68 Neutral Current Problem and Mitigation Techniques: An Overview Karuna Nikum1, Rakesh Saxena2, Abhay Wagh3 1(Department of Electrical Engineering, ACE, Mumbai University, India) 2(SGSITS, RGPV University, Indore, India) 3(Directorate of Technical Education, Mumbai, India ) Abstract: In this paper, an attempt to overview a various number of mitigation techniques and power quality problems associated with neutral current for commercial loads are discussed. The load connected to three phase four wire system are generally single-phase loads and generate triplen harmonic currents due to unbalancing in phases at neutral. There are various neutral current mitigation techniques including active and passive has been discussed. The existing approach and a framework of references for researchers in this field are provided. I. ‘Introduction The ample use of electronic devices in all types of loads i.e. residential, commercial and industrial is adversely affecting the power quality (PQ) of the system[1]-[10]. When three-phase four-wire distribution (3P4W) systems are used to supply single-phase low voltage loads such as lighting ballasts (electronic type), light emitting diodes (LED), compact fluorescent lighting (CFL), personal computers, monitors, laser printers, variable speed drives, adjustable speeds drives (ASD) in air conditioner, UPS systems and other electronic equipment. These loads produces harmonics especially 3rd harmonics in the neutral. In general, the distribution systems designed for linear load type and no longer suitable for delivering large number of non-linear and harmonic generating loads [11]-[15]. The concern PQ issues are high reactive power requirement, harmonic current, low power factor and increased losses[16], [17]. -
Hybrid Synchronous Motor Electromagnetic Torque Research
MATEC Web of Conferences 19, 01026 (2014) DOI: 10.1051/matecconf/201419 01 026 C Owned by the authors, published by EDP Sciences, 2014 Hybrid synchronous motor electromagnetic torque research Elena E. Suvorkovaa, Lev K. Burulko National Research Tomsk Polytechnic University, 634050 Tomsk, Russia Abstract. Electromagnetic field distribution models in reluctance and permanent magnet parts were made by means of Elcut. Dependences of electromagnetic torque on torque angle were obtained. 1. Introduction Present-day position is inextricably connected with developing process in all components of electric drive: electrical machines, power semiconductors and converters on its base. One of the main electric motors development directions is expanding special motors’ construction range for applying in modern competitive object-orientated systems. Electric machines prospects of promotion lead to its non-traditional usage such as hybrid synchronous motor (HSM). HSM main principles of operation make it possible to use as executive engine in a number of production plants, such as artificial fiber production [1]. Electric drive projecting involves verification and regulation method choice which are determined by main electric machine characteristics. Thus main goals of this paper are hybrid synchronous motor air-gap magnetic field research and electromagnetic torque main parts determination. 2. Problem statement HSM is a machine with stator created on basis of serial asynchronous motor and rotor consisting on two parts. The main rotor part is a reluctance machine which is 70% of active rotor length [2], the other is synchronous permanent-magnet machine which is 30% [1]. Power is developed by reluctance machine as the cheapest and simple in design, and energy of constant magnets poles is used for increasing power and improving operational characteristics. -
Rita MBAYED Contribution to the Control of the Hybrid Excitation
Année 2012 UNIVERSITE DE CERGY PONTOISE THESE Présentée pour obtenir le grade de DOCTEUR DE L’UNIVERSITE DE CERGY PONTOISE Ecole doctorale: Sciences et Ingénierie Spécialité: Génie Electrique Soutenance publique prévue le 12 Décembre 2012 Par Rita MBAYED Contribution to the Control of the Hybrid Excitation Synchronous Machine for Embedded Applications JURY Rapporteurs : Prof. Gérard CHAMPENOIS Université de Poitiers Prof. Eric SEMAIL Ecole Nationale d'Arts et Métiers ParisTech Examinateurs : Prof. Francis LABRIQUE Université Catholique de Louvain Prof. Mohamed GABSI Ecole Normale Supérieure Cachan Dr. Vincent LANFRANCHI Université de Technologie de Compiègne Directeur de thèse : Prof. Eric MONMASSON Université de Cergy Pontoise Co-directeurs : Prof. GeorgesSALLOUM Université Libanaise Dr. Lionel VIDO Université de Cergy Pontoise Laboratoire SATIE - UCP/UMR 8029, 1 rue d’Eragny, 95031 Neuville sur Oise France The secret is comprised in three words: Work, finish, publish. Michael Faraday Ere many generations pass, our machinery will be driven by a power obtainable at any point of the universe. This idea is not novel. Men have been led to it long ago by instinct or reason; it has been expressed in many ways, and in many places, in the history of old and new. We find it in the delightful myth of Antheus, who derives power from the earth; we find it among the subtle speculations of one of your splendid mathematicians and in many hints and statements of thinkers of the present time. Throughout space there is energy. Is this energy static or kinetic? If static our hopes are in vain; if kinetic - and this we know it is, for certain - then it is a mere question of time when men will succeed in attaching their machinery to the very wheelwork of nature. -
Linear Shaft Motor Vs
Linear Shaft Motor vs. Other Linear Technologies Linear Shaft Motor Traditionally, linear electric motors have been designed by Linear Shaft Motor “opening out flat” their rotary counterparts. For every rotary motor there is a linear motion counterpart, although the opposite of this No influence from Coil Magnets statement may not always be true. Thus, corresponding to the change in gap DC motor and AC induction, stepper and synchronous motor, we Standard Linear Motor have the Linear DC Motor (DCLM), Linear Induction Motor (LIM), Linear Pulse Motor (LPM), and Linear Synchronous Motor (LSM), respectively. Although this does provide a solution, a number of Cogging by concentration of flux inherent disadvantages arise. Absorption force Like the voice coil motor, the force velocity (FV) curve of the Linear Shaft Motor is a straight line from peak velocity to peak force. The Linear Shaft Motor’s FV curves are split into three regions. The first is what we call Continuous Force. It is the region in which the motor can operate indefinitely without the need for any external cooling, including heat sinks. The second is Acceleration Force, which is the amount of force that can be delivered by the motor for 40 seconds without the need for any external cooling. The third region, the Peak Force, is limited only by the power which can be supplied and the duty cycle. It is limited to 1 to 2 seconds. Your local Nippon Pulse application engineer can help you map this for your particular application. The Linear Shaft Motor is a very simple design that consists of a coil assembly (forcer), which encircles a patented round magnetic shaft. -
Apermanent Magnet Synchronous Motor for an Electric Vehicle
TRITA-ETS-2004-04 ISSN 1650-674x ISRN KTH/R 0404-SE ISBN 91-7283-803-5 A PERMANENT MAGNET SYNCHRONOUS MOTOR FOR AN ELECTRIC VEHICLE - DESIGN ANALYSIS Yung-kang Chin Stockholm 2004 ELECTRICAL MACHINES AND POWER ELECTRONICS DEPARTMENT OF ELECTRICAL ENGINEERING ROYAL INSTITUTE OF TECHNOLOGY SWEDEN Submitted to the School of Computer Science, Electrical Engineering and Engineering Physics, KTH, in partial fulfilment of the requirements for the degree of Technical Licentiate. Copyright © Yung-kang Chin, Sweden, 2004 Printed in Sweden Universitetsservice US AB TRITA-ETS-2004-04 ISSN 1650-674x ISRN KTH/R 0404-SE ISBN 91-7283-803-5 PPrreeffaaccee This technical licentiate thesis deals with the design analysis of a permanent magnet synchronous motor for an electric vehicle. A thesis is a report that conveys the used theoretical approach and the experimental results on a specific problem in a specific area. A thesis could also develop a purely theoretical approach to a topic. It is my aim as the author to present these findings and theoretical approaches clearly and effectively with this concise report. Never Say Never! This is the phrase I have always referred to and it even appears on my screensaver. When I started my doctoral study at KTH, my plan was to write my doctoral dissertation directly without taking the licentiate examination. Well, as I am now writing the preface of my licentiate thesis, my thought has obviously changed through out the duration of the project work. A good friend of mine, who has a PhD degree in Physics himself, once told me that working on a doctoral degree is just like walking through a long dark tunnel. -
What Is a Synchronous AC Motor? Hysteresis and Reluctance Type Designs
A TECHNICAL PAPER FROM BODINE ELECTRIC COMPANY What Is a Synchronous AC Motor? Hysteresis and Reluctance Type Designs Introduction The difference between the speed of the rotating magnetic field of an induction motor (which is always synchronous) and the speed of the rotor is known as “slip.” When the rotor design enables it to “lock into step” with the field, the slip is reduced to zero and the motor is said to run at synchronous speed. Upon reaching the running mode, synchronous motors operate at constant speed -- the speed being dependent on the frequency of the power supply. This constant speed feature makes fixed-speed AC synchronous motors an ideal, low-cost solution for timing and other applications requiring a constant speed output, and without the need for a motor speed control. Design and Operation There are two common types of small synchronous AC induction motors, classified according to the type of rotor used: AMPS RPMs Pull In Pull Out HP a) hysteresis synchronous motors. 2.0 2000 0.10 b) reluctance synchronous motors 1.6 1600 0.08 1. Hysteresis-type AC synchronous motors: Unlike squirrel- cage rotor AC induction motors, this motor type develops 1.2 1200 0.06 torque because of the magnetic hysteresis loss induced in its permanent magnet alloy rotor core. Although the stator 0.8 800 0.04 in a hysteresis synchronous design is wound much like that FULL LOAD of the conventional squirrel cage motor, its rotor is made of 0.4 400 0.02 a heat-treated cast permanent magnet alloy cylinder (with a nonmagnetic support) securely mounted to the shaft. -
BASIC CONCEPTS of MODELING 3 Phase Synchronous Machine With
UNIT I - BASIC CONCEPTS OF MODELING 3 phase synchronous machine with and without damper bars and 3 - phase induction machine Introduction: It was shown in an earlier chapter that an alternator driven at a constant speed produces an alternating voltage at a fixed frequency dependent on the number of poles in the machine. A machine designed to be connected to the supply and run at synchronous speed is referred to as a synchronous machine. The description applies to both motors and generators. A synchronous condenser is a special application of a synchronous motor. While the synchronous motor has only one generally used name, the synchronous generator is on occasion referred to as an alternator or as an a.c. generator. The term alternator has been used in previous chapters and will be used in this chapter but it should be remembered that other terms are in use. In general, the principles of construction and operation are similar for both alternators and generators, just as there were basic similarities between d.c. motors and generators. While alternators were once seldom seen outside power houses and whole communities were supplied from a central source, there is now an expanding market for smaller sized alternators suitable for the provision of power for portable tools. Today, with the growth in computer control, there is a further need for standby generating plant to ensure a continuity of supply to prevent a loss of data from computer memories. So much information is being stored in computers today that even brief interruptions to the power supplies can have serious consequences on the accuracy and extent of information stored. -
Two-Phase Auto-Piloted Synchronous Motors and Actuators
IMPERIAL COLLEGE OF SCIENCE AND TECHNOLOGY DEPARTMENT OF ELECTRICAL ENGINEERING TWO-PHASE AUTO-PILOTED SYNCHRONOUS MOTORS AND ACTUATORS it Thesis submitted for the degree of Doctor of Philosophy of the University of London. it by Amadeu Leao Santos Rodrigues, M.Sc. (D.I.C.) July 1983 The thesis is concerned with certain aspects of the design and per- formance of drives based on variable speed synchronous motors fed from variable frequency sources, controlled by means of rotor-position sensors. This auto-piloted or self-synchronised form of control enables the machine to operate either with an adjustable load angle or an adjustable torque angle depending on whether a voltage or a current source feed is used. D.c. machine-type characteristics can thus be obtained from the system. The thesis commences with an outline of some fundamental design aspects and a summary of torque production mechanisms in electrical machines. The influence of configuration and physical size on machine performance is discussed and the advantages of the use for servo applic- ations of direct-drive as opposed to step-down transmissions are explained. Developments in permanent magnet materials have opened the way to permanent magnet motors of improved performance, and a brief review of the properties of the various materials presently available is given. A finite-difference method using magnetic scalar potential for calculating the magnetic field of permanent magnets in the presence of iron cores and macroscopic currents is described. A comparison with the load line method is made for some typical cases. Analogies between the mechanical commutator of a d.c.