Alternator for Forklift

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Alternator for Forklift Forklift Alternators - An alternator is actually a device that transforms mechanical energy into electrical energy. It does this in the form of an electric current. In principal, an AC electric generator could be referred to as an alternator. The word typically refers to a small, rotating machine driven by automotive and other internal combustion engines. Alternators that are placed in power stations and are powered by steam turbines are actually called turbo-alternators. The majority of these machines utilize a rotating magnetic field but occasionally linear alternators are likewise utilized. A current is produced within the conductor whenever the magnetic field around the conductor changes. Usually the rotor, a rotating magnet, spins within a set of stationary conductors wound in coils. The coils are situated on an iron core called the stator. When the field cuts across the conductors, an induced electromagnetic field otherwise called EMF is generated as the mechanical input causes the rotor to turn. This rotating magnetic field produces an AC voltage in the stator windings. Normally, there are 3 sets of stator windings. These physically offset so that the rotating magnetic field induces 3 phase currents, displaced by one-third of a period with respect to each other. In a "brushless" alternator, the rotor magnetic field could be caused by induction of a permanent magnet or by a rotor winding energized with direct current through brushes and slip rings. Brushless AC generators are normally found in larger machines than those used in automotive applications. A rotor magnetic field can be induced by a stationary field winding with moving poles in the rotor. Automotive alternators usually make use of a rotor winding that allows control of the voltage generated by the alternator. It does this by changing the current in the rotor field winding. Permanent magnet devices avoid the loss due to the magnetizing current in the rotor. These machines are restricted in size because of the cost of the magnet material. As the permanent magnet field is constant, the terminal voltage varies directly with the generator speed..

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Nikola Tesla
Nikola Tesla Nikola Tesla Tesla c. 1896 10 July 1856 Born Smiljan, Austrian Empire (modern-day Croatia) 7 January 1943 (aged 86) Died New York City, United States Nikola Tesla Museum, Belgrade, Resting place Serbia Austrian (1856–1891) Citizenship American (1891–1943) Graz University of Technology Education (dropped out) ‹ The template below (Infobox engineering career) is being considered for merging. See templates for discussion to help reach a consensus. › Engineering career Electrical engineering, Discipline Mechanical engineering Alternating current Projects high-voltage, high-frequency power experiments [show] Significant design o [show] Awards o Signature Nikola Tesla (/ˈtɛslə/;[2] Serbo-Croatian: [nǐkola têsla]; Cyrillic: Никола Тесла;[a] 10 July 1856 – 7 January 1943) was a Serbian-American[4][5][6] inventor, electrical engineer, mechanical engineer, and futurist who is best known for his contributions to the design of the modern alternating current (AC) electricity supply system.[7] Born and raised in the Austrian Empire, Tesla studied engineering and physics in the 1870s without receiving a degree, and gained practical experience in the early 1880s working in telephony and at Continental Edison in the new electric power industry. He emigrated in 1884 to the United States, where he became a naturalized citizen. He worked for a short time at the Edison Machine Works in New York City before he struck out on his own. With the help of partners to finance and market his ideas, Tesla set up laboratories and companies in New York to develop a range of electrical and mechanical devices. His alternating current (AC) induction motor and related polyphase AC patents, licensed by Westinghouse Electric in 1888, earned him a considerable amount of money and became the cornerstone of the polyphase system which that company eventually marketed.
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Rotating Magnetic Field in Induction Motor
Rotating Magnetic Field in AC Machines 1 Introduction In a DC machine, the stator winding is excited by DC current and hence the field produced by this wind- ing is time invariant in nature. In this machine the conversion of energy from electrical to mechanical form or vice versa is possible by one of the following ways: 1. rotating the rotor in the field produced by the stator 2. feeding external dc current through carbon brushes to the rotor 2 Pre-lab questions Let, XX = Last two digits of your roll number g1(t) = cos(!t) and g2(t; θ) = cos(!t) cos(θ) 1. Take ! = 2πf, where f = XX × 50. Vary !t from 0 to 2π. Plot g1(t) vs t using MATLAB (or any other suitable software) 2. Take ! = 2πf, where f = XX × 50. Vary !t from 0 to 2π. Take θ = 0 to 2π. Plot g2(t; θ) vs t; for θ = XX Plot g2(t; θ) vs θ; for !t = 0; π=4; π=2; 2π=3 3 Theory Now consider three coils A, B and C of N turns each, displaced in space by 120◦ and connected to a balanced 3 phase system as shown in Fig. 1. (Note that the stator winding of 3 phase induction machine is distributed in a large number of slots as shown in Fig. 2). The expressions for the current Figure 1: Coil arrangement to produce rotating magnetic field 1 drawn by these coils are given by: ia = I sin(!st) o ib = I sin(!st + 120 ) (1) o ic = I sin(!st + 240 ) where !s = 2πF1 is supply frequency in rad/s and F1 is supply frequency in Hertz.
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Up-And-Coming Physical Concepts of Wireless Power Transfer
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Rotating Magnets Produce a Prompt Analgesia Effect in Rats
Loyola University Chicago Loyola eCommons Biology: Faculty Publications and Other Works Faculty Publications 2012 Rotating Magnets Produce a Prompt Analgesia Effect in Rats Zhong Chen Southern Medical University (China) Hui Ye Loyola University Chicago, [email protected] Haiyun Xu Shantou University Shukang An Southern Medical University (China) Anmin Jin Southern Medical University (China) See next page for additional authors Follow this and additional works at: https://ecommons.luc.edu/biology_facpubs Part of the Biology Commons Recommended Citation Z. Chen, H. Ye, H. Xu, S. An, A. Jin, C. Zhou, and S. Yang, "Rotating magnets produce a prompt analgesia effect in rats," Progress In Electromagnetics Research M, Vol. 27, 203-217, 2012. This Article is brought to you for free and open access by the Faculty Publications at Loyola eCommons. It has been accepted for inclusion in Biology: Faculty Publications and Other Works by an authorized administrator of Loyola eCommons. For more information, please contact [email protected]. This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License. © The Electromagnetics Academy, 2012. Authors Zhong Chen, Hui Ye, Haiyun Xu, Shukang An, Anmin Jin, Chusong Zhou, and Shaoan Yang This article is available at Loyola eCommons: https://ecommons.luc.edu/biology_facpubs/45 Progress In Electromagnetics Research M, Vol. 27, 203{217, 2012 ROTATING MAGNETS PRODUCE A PROMPT ANALGESIA EFFECT IN RATS Zhong Chen1, *, Hui Ye2, Haiyun Xu3, Shukang An1, Anmin Jin1, Chusong Zhou1, and Shaoan Yang1 1Department of Spinal Surgery, Southern Medical University, Zhujiang Hospital, GuangZhou 510282, China 2Department of Biology, Loyola University, Chicago, IL 60660, US 3Department of Anatomy, Medical College, Shantou University, Guangdong 515041, China Abstract|The bene¯cial e®ects of chronic/repeated magnetic stimulation on humans have been examined in previous studies.
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Induction Motor
Chapter 5 ©2010, The McGraw-Hill Companies, Inc. ROTATING MAGNETIC FIELD ©2010, The McGraw-Hill Companies, Inc. 1 A rotating magnetic field is the key to the operation of AC motors. The magnetic field of the stator is made to rotate electrically around and around in a circle. Stator Lamination S N Stator Rotating Magnetic Field Stator Windings ©2010, The McGraw-Hill Companies, Inc. A second magnetic field, that of the rotor, is made to follow the rotating field of the stator by being attracted and repelled by it. Rotor Laminations S N Rotor Magnetic Field Follows That Of The Stator Rotor Windings ©2010, The McGraw-Hill Companies, Inc. 2 Three sets of stator windings are placed 120 electrical degrees apart with each set connected to one phase of the 3-phase power supply When 3-phase current passes through the stator windings, a rotating magnetic field effect is produced that travels around the inside of the stator core. ©2010, The McGraw-Hill Companies, Inc. When 3-phase current passes through the stator windings, a rotating magnetic field effect that travels around the inside of the stator core is set up. 1 3 5 7 2 4 6 ©2010, The McGraw-Hill Companies, Inc. 3 Polarity of the rotating magnetic field is shown at six selected positions marked off at 60° intervals on the sine waves representing the current flowing in the three phases, A, B, and C. ©2010, The McGraw-Hill Companies, Inc. Simply interchanging any two of the three-phase power input leads to the stator windings reverses direction of rotation of the magnetic field.
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* Tesla’s Connection to Columbia University by Kenneth L. Corum and James F. Corum, Ph.D. “The invention of the wheel was perhaps rather obvious; but the invention of an invisible wheel, made of nothing but a magnetic field, was far from obvious, and that is what we owe to Nikola Tesla.” Professor Reginald Kapp, 1956 INTRODUCTION The Electrical Engineering curriculum at Columbia University, though not the first in the US, is one of the oldest and most respected EE programs in the world. From the beginning, a conscientious effort was made to base it on a foundation of science. It has been guided by the specific philosophy stated by Professor Michael Pupin: “Professor Crocker and I maintained that there is an ‘electrical science’ which is the real soul of electrical engineering.” Arguably the most stunning and significant lecture in modern history was presented one spring evening, more than a century ago, at Columbia University. The wealth of nations turned on its merits. Weighing on the balances would be our vast cities, civilization, and quality of life. But, what was it? . .Whatever it was, its impact has been as momentous for the progress and prosperity of civilization as the invention of the wheel! . It was Tesla’s great discovery and analysis of the rotating magnetic field, and a means for the electrical distribution of energy.1 As a result of the analysis presented in this lecture, the great Falls of Niagara would soon be harnessed for the benefit of mankind and launch civilization into the “Electromagnetic Century”. The Engineering Council for Professional Development (now called ABET) has defined “Engineering” as “that profession which utilizes the resources of the planet for the benefit of mankind”.
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Chapter 3 Model of a Three-Phase Induction Motor
CHAPTER 3 MODEL OF A THREE-PHASE INDUCTION MOTOR 3.1 Introduction The induction machine is used in wide variety of applications as a means of converting electric power to mechanical power. Pump steel mill, hoist drives, household applications are few applications of induction machines. Induction motors are most commonly used as they offer better performance than other ac motors. In this chapter, the development of the model of a three-phase induction motor is examined starting with how the induction motor operates. The derivation of the dynamic equations, describing the motor is explained. The transformation theory, which simplifies the analysis of the induction motor, is discussed. The steady state equations for the induction motor are obtained. The basic principles of the operation of a three phase inverter is explained, following which the operation of a three phase inverter feeding a induction machine is explained with some simulation results. 3.2. Basic Principle Of Operation Of Three-Phase Induction Machine The operating principle of the induction motor can be briefly explained as, when balanced three phase voltages displaced in time from each other by angular intervals of 120o is applied to a stator having three phase windings displaced in space by 120o electrical, a rotating magnetic field is produced. This rotating magnetic field 45 has a uniform strength and rotates at the supply frequency, the rotor that was assumed to be standstill until then, has electromagnetic forces induced in it. As the rotor windings are short circuited, currents start circulating in them, producing a reaction. As known from Lenz’s law, the reaction is to counter the source of the rotor currents.
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School of Physical Sciences
SCHOOL OF PHYSICAL SCIENCES LOW POWER, LONG DURATION ROTAMAK DISCHARGES IN ARGON B.L. JESSUP and J. TENDYS FUPH-R-180 FEBRUARY, 1982 LOW POKER, LONG DURATION ROTAMAK DISCHARGES IN ARGON B.L. Jessup and J. Tendys* School of Physical Sciences The Flinders University of South Australia Bedford Park, 5042, Australia ABSTRACT An investigation was made of a Rotamak compact torus configuration in which the rotating magnetic field used to drive the toroidal current was generated by a pulsed 6 KW R.F. oscillator. The toroidal current was measured together with the vertical component of the magnetic field both along the vertical axis and as a function of radius in the midplane of the current ring. The experimental results show that a Rotamak equilibrium, apparently stable for several milliseconds, could be obtained. Toroidal plasma currents of several hundred amps were observed with argon filling pressures around 0.2 mTon and applied vertical equilibrium fields of about 1 m Tesla. * Visiting Scholar, on attachment from the Australian Atomic Energy Commission. 1. I. INTRODUCTION The R^tamak concept, which uses a rotating magnetic field to drive the steady toroidal current in a compact torus device, has been studied experimentally using high power (10 Mm"), short time (60 usee) rotating magnetic field pulses produced by line generators (W.H. HUGRASS, I.R. JONES, K.F. McKENNA, N.G.R. PHILLIPS, R.G. STORER, and H. TUCZEK, 1980). It is of considerable interest to extend this study to longer lived Rotamak plasmas- The objective of these experiments was to verity the maintenance of an equilibrium configuration of milli-second lifetime.
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Design of Tesla's Two-Phase Inductor
X International Symposium on Industrial Electronics INDEL 2014, Banja Luka, November 0608, 2014 Design of Tesla’s Two-Phase Inductor Đorđe M. Lekić, Petar R. Matić University of Banja Luka Faculty of Electrical Engineering Banja Luka, Republic of Srpska, Bosnia and Herzegovina [email protected], [email protected] Abstract—This paper describes a new method for designing Tesla’s two-phase inductor for demonstration of rotating I. INTRODUCTION magnetic field, based on the famous Tesla’s Egg of Columbus In February 1882, the Serbian inventor and scientist Nikola experiment. The design is based on electromagnetic and thermal Tesla came up with the design of the rotating magnetic field analytical models of the two-phase inductor and verified by and in 1888 he constructed the first induction motor. Tesla’s computer simulation and FEM analysis. first induction motor had a toroidal stator with a two-phase Keywords-FEM analysis; rotating magnetic field; single-phase inductor, unlike a cylindrical stator with a three phase inductor induction motor; Tesla’s Egg of Columbus; which is nowadays a standard design. In order to demonstrate the effects of the rotating magnetic field at the World fair exhibition in Chicago in 1893, Tesla used his two-phase NOMENCLATURE inductor to lift and spin a metal egg, thus “performing the feat D, d Outer and inner iron core diameter [mm], of Columbus without cracking the egg”[1]. Tesla’s original a, h Iron core width and height [mm], design of the two-phase inductor is shown in Fig. 1. -7 μ0 = 4π·10 Permeability
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Vector Analysis Application in Rotating Magnetic Fields
2002-578 VECTOR ANALYSIS APPLICATION IN ROTATING MAGNETIC FIELDS Bruno Osorno Department of Electrical And Computer Engineering California State University Northridge 18111 Nordhoff St Northridge CA 91330-8436 Email:[email protected] Abstract Rotating magnetic fields in three-phase electrical machines has been one of the hardest topics to convey to our students in the area of energy conversion. These fields are transformed into phasors (vectors) that rotate in space around the stator of an electrical machine. The mathematical proof of such rotation will be shown and a MATLAB simulation describing these vectors will be given. Classic textbooks approach this concept mathematically and usually the students are left to imagine the space vector rotation. This is no longer the case, now we can simulate and SEE in our desktop computers, using MatlabTM, rotating phasors. Polyphase Analysis Three phase induction machines are the work-horse of industry, and these machines have a “rotating magnetic field”. We will give a brief physical description; consider a sequence a-b-c and a symmetric distribution of the phases by 1200 electrical degrees each in space and around the air gap. The basic three-phase machine will have three coils that we consider to have the following terminals: a a’ b b’ c c’ These coils are excited by a time dependent sinusoidal alternating current producing a sinusoidal magneto-motive force (mmf) wave at the center of the magnetic axis of particular phase. Therefore the three-space sinusoidal mmf waves are displaced 1200 electrical degrees in space. Figure 1 shows how we determine the magnetic axis of a coil.
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Title Two- and Three-Dimensional Omnidirectional Wireless Power
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by HKU Scholars Hub Two- and Three-Dimensional Omnidirectional Wireless Power Title Transfer Author(s) Ng, WMR; ZHANG, C; Lin, D; Hui, SYR IEEE Transactions on Power Electronics, 2014, v. 29, p. 4470- Citation 4474 Issued Date 2014 URL http://hdl.handle.net/10722/199099 Rights Creative Commons: Attribution 3.0 Hong Kong License 4470 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 29, NO. 9, SEPTEMBER 2014 Letters Two- and Three-Dimensional Omnidirectional Wireless Power Transfer Wai Man Ng, Member, IEEE, Cheng Zhang, Deyan Lin, Member, IEEE, and S. Y. Ron Hui, Fellow, IEEE Abstract—Nonidentical current control methods for 2- and 3-D omnidirectional wireless power systems are described. The omni- directional power transmitter enables ac magnetic flux to flow in all directions and coil receivers to pick up energy in any position in the proximity of the transmitter. It can be applied to wireless charging systems for low-power devices such as radio-frequency identifica- tion devices and sensors. Practical results on 2-D and 3-D systems have confirmed the omnidirectional power transfer capability. Index Terms—Inductive power, magnetic resonance, wireless power transfer. I. INTRODUCTION IRELESS power pioneered by Tesla a century ago can W be classified as radiative and nonradiative. In communi- cation, omnidirectional antenna is a class of antenna that radiates signals in all directions [1]. For nonradiative applications, most of the low-power [2]–[4] and medium/high-power [5] wire- less power applications have their power flow guided by coil Fig.
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