Chapter 3 Model of a Three-Phase Induction Motor
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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. -
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. -
Up-And-Coming Physical Concepts of Wireless Power Transfer
Up-And-Coming Physical Concepts of Wireless Power Transfer Mingzhao Song1,2 *, Prasad Jayathurathnage3, Esmaeel Zanganeh1, Mariia Krasikova1, Pavel Smirnov1, Pavel Belov1, Polina Kapitanova1, Constantin Simovski1,3, Sergei Tretyakov3, and Alex Krasnok4 * 1School of Physics and Engineering, ITMO University, 197101, Saint Petersburg, Russia 2College of Information and Communication Engineering, Harbin Engineering University, 150001 Harbin, China 3Department of Electronics and Nanoengineering, Aalto University, P.O. Box 15500, FI-00076 Aalto, Finland 4Photonics Initiative, Advanced Science Research Center, City University of New York, NY 10031, USA *e-mail: [email protected], [email protected] Abstract The rapid development of chargeable devices has caused a great deal of interest in efficient and stable wireless power transfer (WPT) solutions. Most conventional WPT technologies exploit outdated electromagnetic field control methods proposed in the 20th century, wherein some essential parameters are sacrificed in favour of the other ones (efficiency vs. stability), making available WPT systems far from the optimal ones. Over the last few years, the development of novel approaches to electromagnetic field manipulation has enabled many up-and-coming technologies holding great promises for advanced WPT. Examples include coherent perfect absorption, exceptional points in non-Hermitian systems, non-radiating states and anapoles, advanced artificial materials and metastructures. This work overviews the recent achievements in novel physical effects and materials for advanced WPT. We provide a consistent analysis of existing technologies, their pros and cons, and attempt to envision possible perspectives. 1 Wireless power transfer (WPT), i.e., the transmission of electromagnetic energy without physical connectors such as wires or waveguides, is a rapidly developing technology increasingly being introduced into modern life, motivated by the exponential growth in demand for fast and efficient wireless charging of battery-powered devices. -
Direct Torque Control of Induction Motors
DIRECT TORQUE CONTROL FOR INDUCTION MOTOR DRIVES MAIN FEATURES OF DTC · Decoupled control of torque and flux · Absence of mechanical transducers · Current regulator, PWM pulse generation, PI control of flux and torque and co-ordinate transformation are not required · Very simple control scheme and low computational time · Reduced parameter sensitivity BLOCK DIAGRAM OF DTC SCHEME + _ s* s j s + Djs _ Voltage Vector s * T + j s DT Selection _ T S S S s Stator a b c Torque j s s E Flux vs 2 Estimator Estimator 3 s is 2 i b i a 3 Induction Motor In principle the DTC method selects one of the six nonzero and two zero voltage vectors of the inverter on the basis of the instantaneous errors in torque and stator flux magnitude. MAIN TOPICS Þ Space vector representation Þ Fundamental concept of DTC Þ Rotor flux reference Þ Voltage vector selection criteria Þ Amplitude of flux and torque hysteresis band Þ Direct self control (DSC) Þ SVM applied to DTC Þ Flux estimation at low speed Þ Sensitivity to parameter variations and current sensor offsets Þ Conclusions INVERTER OUTPUT VOLTAGE VECTORS I Sw1 Sw3 Sw5 E a b c Sw2 Sw4 Sw6 Voltage-source inverter (VSI) For each possible switching configuration, the output voltages can be represented in terms of space vectors, according to the following equation æ 2p 4p ö s 2 j j v = ç v + v e 3 + v e 3 ÷ s ç a b c ÷ 3 è ø where va, vb and vc are phase voltages. -
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. -
The Fundamentals of Ac Electric Induction Motor Design and Application
THE FUNDAMENTALS OF AC ELECTRIC INDUCTION MOTOR DESIGN AND APPLICATION by Edward J. Thornton Electrical Consultant E. I. du Pont de Nemours Houston, Texas and J. Kirk Armintor Senior Account Sales Engineer Rockwell Automation The Woodlands, Texas Edward J. (Ed) Thornton is an Electrical Electrical Mechanical Consultant in the Electrical Technology Coupling System Field System Consulting Group in Engineering at DuPont, in Houston, Texas. His specialty is the design, operation, and maintenance of electric power distribution systems and large motor installations. He has 20 years E , I T , w of consulting experience with DuPont. Mr. Thornton received his B.S. degree Figure 1. Block Representation of Energy Conversion for Motors. (Electrical Engineering, 1978) from Virginia Polytechnic Institute and State University. The coupling magnetic field is key to the operation of electrical He is a registered Professional Engineer in the State of Texas. apparatus such as induction motors. The fundamental laws associated with the relationship between electricity and magnetism were derived from experiments conducted by several key scientists J. Kirk Armintor is a Senior Account in the 1800s. Sales Engineer in the Rockwell Automation Houston District Office, in The Woodlands, Basic Design and Theory of Operation Texas. He has 32 years’ experience with The alternating current (AC) induction motor is one of the most motor applications in the petroleum, rugged and most widely used machines in industry. There are two chemical, paper, and pipeline industries. major components of an AC induction motor. The stationary or He has authored technical papers on motor static component is the stator. The rotating component is the rotor. -
Abstract Controlling Ac Motor Using Arduino
ABSTRACT CONTROLLING AC MOTOR USING ARDUINO MICROCONTROLLER Nithesh Reddy Nannuri, M.S. Department of Electrical Engineering Northern Illinois University, 2014 Donald S Zinger, Director Space vector modulation (SVM) is a technique used for generating alternating current waveforms to control pulse width modulation signals (PWM). It provides better results of PWM signals compared to other techniques. CORDIC algorithm calculates hyperbolic and trigonometric functions of sine, cosine, magnitude and phase using bit shift, addition and multiplication operations. This thesis implements SVM with Arduino microcontroller using CORDIC algorithm. This algorithm is used to calculate the PWM timing signals which are used to control the motor. Comparison of the time taken to calculate sinusoidal signal using Arduino and CORDIC algorithm was also done. NORTHERN ILLINOIS UNIVERSITY DEKALB, ILLINOIS DECEMBER 2014 CONTROLLING AC MOTOR USING ARDUINO MICROCONTROLLER BY NITHESH REDDY NANNURI ©2014 Nithesh Reddy Nannuri A THESIS SUBMITTED TO THE GRADUATE SCHOOL IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE MASTER OF SCIENCE DEPARTMENT OF ELECTRICAL ENGINEERING Thesis Director: Dr. Donald S Zinger ACKNOWLEDGEMENTS I would like to express my sincere gratitude to Dr. Donald S. Zinger for his continuous support and guidance in this thesis work as well as throughout my graduate study. I would like to thank Dr. Martin Kocanda and Dr. Peng-Yung Woo for serving as members of my thesis committee. I would like to thank my family for their unconditional love, continuous support, enduring patience and inspiring words. Finally, I would like to thank my friends and everyone who has directly or indirectly helped me for their cooperation in completing the thesis. -
Electric Motors
SPECIFICATION GUIDE ELECTRIC MOTORS Motors | Automation | Energy | Transmission & Distribution | Coatings www.weg.net Specification of Electric Motors WEG, which began in 1961 as a small factory of electric motors, has become a leading global supplier of electronic products for different segments. The search for excellence has resulted in the diversification of the business, adding to the electric motors products which provide from power generation to more efficient means of use. This diversification has been a solid foundation for the growth of the company which, for offering more complete solutions, currently serves its customers in a dedicated manner. Even after more than 50 years of history and continued growth, electric motors remain one of WEG’s main products. Aligned with the market, WEG develops its portfolio of products always thinking about the special features of each application. In order to provide the basis for the success of WEG Motors, this simple and objective guide was created to help those who buy, sell and work with such equipment. It brings important information for the operation of various types of motors. Enjoy your reading. Specification of Electric Motors 3 www.weg.net Table of Contents 1. Fundamental Concepts ......................................6 4. Acceleration Characteristics ..........................25 1.1 Electric Motors ...................................................6 4.1 Torque ..............................................................25 1.2 Basic Concepts ..................................................7 -
Alternator for Forklift
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. -
Improvement of Electromagnetic Railgun Barrel Performance and Lifetime By
IMPROVEMENT OF ELECTROMAGNETIC RAILGUN BARREL PERFORMANCE AND LIFETIME BY METHOD OF INTERFACES AND AUGMENTED PROJECTILES A Thesis Presented to the Faculty of California Polytechnic State University San Luis Obispo In Partial Fulfillment of the Requirements for the Degree Master of Science in Aerospace Engineering by Aleksey Pavlov June 2013 c 2013 Aleksey Pavlov ALL RIGHTS RESERVED ii COMMITTEE MEMBERSHIP TITLE: Improvement of Electromagnetic Rail- gun Barrel Performance and Lifetime by Method of Interfaces and Augmented Pro- jectiles AUTHOR: Aleksey Pavlov DATE SUBMITTED: June 2013 COMMITTEE CHAIR: Kira Abercromby, Ph.D., Associate Professor, Aerospace Engineering COMMITTEE MEMBER: Eric Mehiel, Ph.D., Associate Professor, Aerospace Engineering COMMITTEE MEMBER: Vladimir Prodanov, Ph.D., Assistant Professor, Electrical Engineering COMMITTEE MEMBER: Thomas Guttierez, Ph.D., Associate Professor, Physics iii Abstract Improvement of Electromagnetic Railgun Barrel Performance and Lifetime by Method of Interfaces and Augmented Projectiles Aleksey Pavlov Several methods of increasing railgun barrel performance and lifetime are investigated. These include two different barrel-projectile interface coatings: a solid graphite coating and a liquid eutectic indium-gallium alloy coating. These coatings are characterized and their usability in a railgun application is evaluated. A new type of projectile, in which the electrical conductivity varies as a function of position in order to condition current flow, is proposed and simulated with FEA software. The graphite coating was found to measurably reduce the forces of friction inside the bore but was so thin that it did not improve contact. The added contact resistance of the graphite was measured and gauged to not be problematic on larger scale railguns. The liquid metal was found to greatly improve contact and not introduce extra resistance but its hazardous nature and tremendous cost detracted from its usability. -
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. -
Tesla's Polyphase System and Induction Motor
SERBIAN JOURNAL OF ELECTRICAL ENGINEERING Vol. 3, No. 2, November 2006, 121-130 Tesla’s Polyphase System and Induction Motor Petar Miljanić1 1 Introduction While new scientific knowledge is acquired by learning, observation, experiments and thinking, the inventions are mostly the fruit of the intuition of individuals and of their creative impulses. Inventors are people who use consciously or unconsciously the accumulated human knowledge and experi- ence, and find useful solutions for the humanity. Some of those inventions are epochal, like for instance the inventions of the steam and the internal combustion engine. These epochal inventions obviously include the Tesla’s system of poly- phase alternate currents and Tesla’s induction motor. It can be often heard that in some eras of civilization there appear needs and there ripen circumstances for the appearance of great inventions. The sequence of the human acquisition of knowledge of natural phenomena on which the function of the induction motor is based, and the sequence of experiments in the attempt to make the induction motor show that that opinion is not without basis. In the following lines, we will tell the story of the induction motor. That story will not be limited to Tesla’s key contribution only, but it will mention things that happened before and after Tesla’s patent applications by the end of 1887. 2 Discoveries The induction motor rotates thanks to the natural phenomenon which may be described by the following words: the moving magnetic field of one part of the motor, for instance the stator, induces currents in the conducting parts of another part of the motor, the rotor.