DOCSLIB.ORG

Magnetic Levitation (MAGLEV): a Technology on Which Vehicles Propels

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Magnetic Levitation (MAGLEV): a Technology on Which Vehicles Propels International Journal of Applied Engineering Research ISSN 0973-4562 Volume 13, Number 9 (2018) pp. 112-118 © Research India Publications. http://www.ripublication.com Magnetic Levitation (MAGLEV): A Technology on which Vehicles propels. 1 2 3 Mudit Sharma , Manish Kumar Arya , Indrajit Kumar Meerut Institute of Engineering and Technology, Meerut, India Abstract : INTRODUCTION Maglev is a method of propulsion that uses magnetic Magnetic Levitation Transport or Maglev is a form of levitation to propel vehicles with magnets rather than with transportation that suspends guides and propels vehicles wheels, axles and bearings. The technical specifications of via electromagnetic force. This method can be faster than such technology are dominating on the available technical wheeled mass transit systems potentially reaching velocities comparable to turboprop and jet aircraft up to a infrastructure of the existing railways. With maglev, a range of (500 to 600 km/hr.).Maglev trains move more vehicle is levitated a short distance away from a guide way smoothly and somewhat more quietly than other using magnets to create both lift and thrust (levitation conventional trains and they do not rely on traction or would not exceed above 10 cm). Maglev has became the friction, their acceleration and deceleration are faster than fastest growing technology in the field of railways conventional trains,they are unaffected of weather. infrastructure. Maglev trains which are based on the The power needed for levitation is not at all the large principle of maglev have been compared with highspeed amount of the overall energy consumption; most of the power in these trainsare used to overcome air resistance transportations such as air transport. High-speed maglev (drag), as with every high speed form of transport .These trains promise dramatic improvements for human travel trains can move continuously high speeds than the widespread adoption occurs. Maglev trains move more conventional trains,they hold shwethasingh [1] explains smoothly and somewhat more quietly thanwheeled mass about the Magnetic levitation has a very advanced and transit systems. In future these High-speed maglev trains efficient technology. We can use of it in industrial purpose would give a huge competition to the aviation industry. as well as in office and homelike as the fan in buildings, transportation, weapon(gun, rocketry), nuclear reactor, use This paper briefly examines some commercial applications of elevator in civil engineering, toys, pen.So it has many of rare earth magnetsand magnetic levitation and applications which are using in the whole world. It gives summarizes the state of the technology. the clean energy and it’s all application gives the lack of contact and thus no friction. Magnetic levitation improves Keywords- Levitation, Maglev train, Magnet,Guide-way efficiency and life of the system. It reduces the maintenance costs of the system. So we can say it is the future of flying trains and cars. 112 International Journal of Applied Engineering Research ISSN 0973-4562 Volume 13, Number 9 (2018) pp. 112-118 © Research India Publications. http://www.ripublication.com Fig: 1 Arrangement of Magnetic Coils and Magnets MAGLEV TECHNOLOGY: TYPES OF MAGLEV TECHNOLOGY: This technology uses monorail track with linear 1. ELECROMAGNETIC SUSPENSION motors,these trains move on special tracks rather than the 2. ELECTRODYNAMIC SUSPENSION mainstream conventional train tracks they use very powerful electromagnets to reach at higher velocities(Fig- 1. ELECTROMAGNETIC SUSPENSION 1),they float about 1- 10 cms above the guideway on a In this system Electromagnets areattached to the train and magnetic field .These trains are propelled by the also attached to the guide way track. They have guideways once the train is pulled into the next section the ferromagnetic stators on the track and they help them to magnetism switches so that the train is pulled on again . levitate the train. They have guidance magnets on the sides The electro magnets run the length of the guideway. of the track they are laid complete along the track. A computer is used to control the height of levitation of train they make us levitate about ( 1– 15cms ).The Max speed these trains could reach is about 438km/hr. They are fast and give good competition to aviation industry. They have on-board battery power supply which gives surplus amount of energy required to run a cabin. As per figure 2. H.Yaghoubi and H. Ziari[3] (Magnetic fields inside and outside the vehicle are less than the electronicdynamic suspension; is proven, commercially that available technology can attain very high speeds ; no wheels, secondary propulsion system are required due to the system's instability and the required constant corrections by outside systems, vibration issues may occur. 113 International Journal of Applied Engineering Research ISSN 0973-4562 Volume 13, Number 9 (2018) pp. 112-118 © Research India Publications. http://www.ripublication.com Fig: 2 Arrangement of Electromagnetic suspensions 2. Electrodynamics suspension (EDS): suspension (EDS), both the rail and the train exert a H. Behbahani, H. Yaghoubi, and M. A. Rezvani, [2]as per magnetic field, and the train is levitated by the repulsive this system supercooled, superconducting magnets are force between these magnetic fields. The magnetic field in placed under the train.By this system the train could the train is produced by either electromagnets as in JR- Levitate about 10cm.The magneticfield which helps the Maglev or by an array of permanent magnets as in Induct train to levitate is due to use of superconducting magnets. rack. The repulsive force in the track is created by an If these permanent magnets are placed array they would induced magnetic field in wires or other conducting strips also be used as Inductrack system. in the track. It uses a repulsive force between two magnetic fields to push the train away from the rail. In Electrodynamics’ 114 International Journal of Applied Engineering Research ISSN 0973-4562 Volume 13, Number 9 (2018) pp. 112-118 © Research India Publications. http://www.ripublication.com Fig:3 Arrangement of Electrodynamic Suspension MAGLEV TRACK magnetic fields that pull and push the train along the guide The magnetized coil running along the track, called a guide way.[2] The electric current supplied to the coil in guide way, which repels the large magnets on the train’s way walls is constantly alternating to change the polarity undercarriage, allowing the train to levitate between0.39 of the magnetized coils this change in polarity causes the and 3.93 inches (1 to 10 centimeters) above the guide way. magnetic field in front of the train to pull the vehicle Once the train is levitated, power is supplied to the coil forward. within the guide way walls to create a unique system of Fig:4MAGLEVTRACK DEVELOPMENT OF MAGLEV TRAINS: 1. PROPULSION: There are different factors which are used in the H. Behbahani and H. Yaghoubi[6],Some EMS systems development of maglev trains, these help in such as HSST/Linimo can provide both levitation and movement,stability, guidance etc of a train. propulsion using an onboard linear motor. But some EDS 115 International Journal of Applied Engineering Research ISSN 0973-4562 Volume 13, Number 9 (2018) pp. 112-118 © Research India Publications. http://www.ripublication.com systems and some EMS systems are like they can levitate propulsion. A linear motor (propulsion coils) mounted in the train using the magnets on board butcannot propel it the track is one solution. As per fig 5. forward. As such, vehicles need some other technology for Fig: 5 PROPULSION 2. STABILITY: down motions) can be problematic with some technologies. As per Earnshaw's theorem, any combination of static magnets cannot be in a stable equilibrium.Therefore a 3. GUIDANCE: dynamic magnetic field is required to achieve stabilization. Some systems use Null Current systems (also sometimes EMS systems rely on active electronic stabilization called Null Flux systems); they use a coil which is which constantly measure the bearing distance and wound so that it enters two opposing, alternating fields, so adjust the electromagnet current accordingly. All EDS that the average flux in the loop is zero. When the systems rely on changing magnetic fields creating vehicle is in the straight ahead position, no current flows, electrical currents, and these can give passive but if it moves off-line this creates a changing flux stability.Because maglev vehicles essentially fly, that generates a field that naturally pushes and pulls it back stabilization of pitch, roll and yaw is required by magnetic into line. This is the guidance system of maglev technology. In addition to rotation, move forward and trains. backward, sway (sideways motion) or heave (up and Fig:6 Guidance 4. EVACUATED TUBES: malfunction or accident. Some systems (notably the Swissmetro system) propose the use of (vactrain )maglev train technology used in 5. POWER AND ENERGY USAGE: evacuated (airless) tubes, which is used to remove air Energy for the maglev trains is used to accelerate the train, drag. This has the potential to increase speed and and the power could be regained when the train efficiency greatly, as most of the energy for conventional slows down ("regenerative braking"). It is also used to maglev trains is lost due to aerodynamic drag.One make the train levitate and to stabilize the movement of potential risk for passengers of trains operating in the train. At low speeds the percentage of power (energy evacuated tubes is that they could be exposed to the risk of per time) used for levitation can be significant consuming cabin depressurization unless tunnel safety monitoring up to systems can repressurize the tube in the event of a train 116 International Journal of Applied Engineering Research ISSN 0973-4562 Volume 13, Number 9 (2018) pp. 112-118 © Research India Publications. http://www.ripublication.com 15% more power than a subway or light rail service.Also challenging for anything other than point-to-point services.
Load more

Recommended publications
  • An Artificial-Gravity Space-Settlement Ground-Analogue Design Concept
    AIAA 2016-5388 AIAA SPACE Forum 13 - 16 September 2016, Long Beach, California AIAA SPACE 2016 An Artificial-Gravity Space-Settlement Ground-Analogue Design Concept Gregory A. Dorais1 NASA Ames Research Center, Moffett Field, CA, 94035 The design concept of a modular and extensible hypergravity facility is presented. Several benefits of this facility are described including that the facility is suitable as a full- scale artificial-gravity space-settlement ground analogue for humans, animals, and plants for indefinite durations. The design is applicable as an analogue for on-orbit settlements as well as those on moons, asteroids, and Mars. The design creates an extremely long-arm centrifuge using a multi-car hypergravity vehicle travelling on one or more concentric circular tracks. This design supports the simultaneous generation of multiple-gravity levels to explore the feasibility and value of and requirements for such space-settlement designs. The design synergizes a variety of existing technologies including centrifuges, tilting trains, roller coasters, and optionally magnetic levitation. The design can be incrementally implemented such that the facility can be operational for a small fraction of the cost and time required for a full implementation. Brief concept of operation examples are also presented. Nomenclature C = centigrade CFT = cabin floor thickness Ch = cabin height CL = cabin length (m) CLm = the minimum Cabin length margin between top inner cabin corners of adjacent HyperGravity Vehicle (HGV) Cars (HGVC)s, i.e., the length
    [Show full text]
  • Modeling and Simulation of Shanghai MAGLEV Train Transrapid with Random Track Irregularities
    Modeling and Simulation of Shanghai MAGLEV Train Transrapid with Random Track Irregularities Prof. Shu Guangwei M.Sc. Prof. Dr.-Ing. Reinhold Meisinger Prof. Shen Gang Ph.D. Shanghai Institute of Technology, Shanghai, P.R. China Nuremberg University of Applied Sciences, Nuremberg, Germany Tongji University, Shanghai, P.R. China Abstract The MAGLEV Transrapid is a kind of new type high speed train in the world which is levitated and gui- ded over the track using electro magnetic forces. Because the electro magnets are unstable, they ha- ve to be controlled. Since 2002 the worldwide first commercial use of such a high speed train based on German technology is running successfully in Shanghai Pudong Airport, P.R.China. In this paper modeling of the high speed MAGLEV train Transrapid is discussed, which considered the whole mechanical system of one vehicle with optimized suspension parameters and all controlled electro magnet pairs in vertical and lateral directions. The dynamical simulation code is generated with MATLAB/SIMILINK. For the design of the control system, the optimal Linear Quadratic Control for minimum control energy is used for each single electro magnet. The simulation results are presen- ted with the given vertical and lateral random track irregularities. The research work was carried out together with Prof. Shen Gang, Ph.D. during the time Prof. Dr. Meisinger was visiting professor in Shanghai 2006 and Prof. Shu Guangwei, M.Sc. was visiting profes- sor in Nuremberg 2007. ISSN 1616-0762 Sonderdruck Schriftenreihe der Georg-Simon-Ohm-Fachhochschule Nürnberg Nr. 39, Juli 2007 Schriftenreihe Georg-Simon-Ohm-Fachhochschule Nürnberg Seite 3 1.
    [Show full text]
  • By James Powell and Gordon Danby
    by James Powell and Gordon Danby aglev is a completely new mode of physically contact the guideway, do not need The inventors of transport that will join the ship, the engines, and do not burn fuel. Instead, they are the world's first wheel, and the airplane as a mainstay magnetically propelled by electric power fed superconducting Min moving people and goods throughout the to coils located on the guideway. world. Maglev has unique advantages over Why is Maglev important? There are four maglev system tell these earlier modes of transport and will radi- basic reasons. how magnetic cally transform society and the world economy First, Maglev is a much better way to move levitation can in the 21st Century. Compared to ships and people and freight than by existing modes. It is wheeled vehicles—autos, trucks, and trains- cheaper, faster, not congested, and has a much revolutionize world it moves passengers and freight at much high- longer service life. A Maglev guideway can transportation, and er speed and lower cost, using less energy. transport tens of thousands of passengers per even carry payloads Compared to airplanes, which travel at similar day along with thousands of piggyback trucks into space. speeds, Maglev moves passengers and freight and automobiles. Maglev operating costs will at much lower cost, and in much greater vol- be only 3 cents per passenger mile and 7 cents ume. In addition to its enormous impact on per ton mile, compared to 15 cents per pas- transport, Maglev will allow millions of human senger mile for airplanes, and 30 cents per ton beings to travel into space, and can move vast mile for intercity trucks.
    [Show full text]
  • ESHGF Design Concept Final 20151201
    NASA/TM—2015–218935 Modular Extended-Stay HyperGravity Facility Design Concept An Artificial-Gravity Space-Settlement Ground Analogue Gregory A. Dorais, Ph.D. Ames Research Center, Moffett Field, California December 2015 NASA STI Program ... in Profile Since its founding, NASA has been dedicated • CONFERENCE PUBLICATION. to the advancement of aeronautics and space Collected papers from scientific and science. The NASA scientific and technical technical conferences, symposia, seminars, information (STI) program plays a key part in or other meetings sponsored or helping NASA maintain this important role. co-sponsored by NASA. The NASA STI program operates under the • SPECIAL PUBLICATION. Scientific, auspices of the Agency Chief Information Officer. technical, or historical information from It collects, organizes, provides for archiving, and NASA programs, projects, and missions, disseminates NASA’s STI. The NASA STI often concerned with subjects having program provides access to the NTRS Registered substantial public interest. and its public interface, the NASA Technical Reports Server, thus providing one of the largest • TECHNICAL TRANSLATION. collections of aeronautical and space science STI English-language translations of foreign in the world. Results are published in both non- scientific and technical material pertinent to NASA channels and by NASA in the NASA STI NASA’s mission. Report Series, which includes the following report types: Specialized services also include organizing and publishing research results, distributing • TECHNICAL PUBLICATION. Reports of specialized research announcements and completed research or a major significant feeds, providing information desk and personal phase of research that present the results of search support, and enabling data exchange NASA Programs and include extensive data services.
    [Show full text]
  • Flywheel Energy Storage System with Superconducting Magnetic Bearing
    Flywheel Energy Storage System with Superconducting Magnetic Bearing Makoto Hirose * , Akio Yoshida , Hidetoshi Nasu , Tatsumi Maeda Shikoku Research Institute Incorporated , Takamatsu , Kagawa , Japan In an effort to level electricity demand between day and night, we have carried out research activities on a high-temperature superconducting flywheel energy storage system (an SFES) that can regulate rotary energy stored in the flywheel in a noncontact, low-loss condition using superconductor assemblies for a magnetic bearing. These studies are being conducted under a Japanese national project (sponsored by the Agency of Industrial Science and Technology - a unit of the Ministry of International Trade and Industry - and the New Energy and Industrial Technology Development Organization). Phase 1 of the project was carried out on a five-year plan beginning in fiscal 1995 with the participation of 10 interested companies, including Shikoku Research Institute Inc. During the five-year period, we carried out two major studies - one on the operation of a small flywheel system (built as a small-scale model) and the other on superconducting magnetic bearings as an elemental technology for a 10-kWh energy storage system. Of the results achieved in Phase 1 of the project (from October 1995 through March 2000), this paper gives an outline of the small flywheel system (having an energy storage capacity of 0.5 kWh) and reports on progress in the development of magnetic bearings using superconductor assemblies (which we call "superconducting magnetic bearings" or "SMBs"). 1. Small-Scale Model 1.1. System Configuration The small-scale model was built in 1998 mainly for the purpose of demonstrating a control technology for high-speed operation of a rotor levitated in a noncontact condition by a superconducting magnetic bearing.
    [Show full text]
  • 1 Diamagnetic Levitation Using High-Temperature
    Diamagnetic Levitation Using High-Temperature Superconducting Wires for Microgravity Research and Mitigation in Human Spaceflight Applications G. Bruhauga* aUniversity of Rochester, Department of Mechanical Engineering, 235 Hopeman Building, P. O Box 270132, Rochester, NY 14627 USA *[email protected] L. Beveridgeb bLANL Stop E557 PO Box 1663 Los Alamos, NM 87545 [email protected] Key Words: microgravity, diamagnetism, levitation, superconductors A novel use of high-temperature superconducting (HTS) electromagnets for human-sized microgravity research and mitigation is outlined. Recent advances in HTS technology have resulted in electromagnets that potentially could levitate large diamagnetic targets, such as human organs, for additive manufacturing or entire humans for microgravity training. These applications are then used as a springboard to discuss the possibility of active microgravity compensation and “inertial dampeners” for future space travel applications. Finite element simulations are used to check the validity of the designs and motivate future research. 1 1. Introduction The stable levitation of diamagnetic objects has been studied and demonstrated experimentally but has so far had limited applications. Diamagnetic materials weakly repel any magnetic fields that are applied to them [1], but the repulsion is much weaker than with other magnetic effects such as ferromagnetism. This natural phenomenon can be used to levitate any structure that is primarily diamagnetic, as long as the applied magnetic field is extremely strong. Until recently, magnets of the needed strength (of the order of several tesla or greater) were either nonexistent or extremely rare. However, the advent of low-temperature superconductors (LTS’s) as a commercial technology has made several-tesla magnets quite commonplace.
    [Show full text]
  • Review of Magnetic Levitation (MAGLEV): a Technology to Propel Vehicles with Magnets by Monika Yadav, Nivritti Mehta, Aman Gupta, Akshay Chaudhary & D
    Global Journal of Researches in Engineering Mechanical & Mechanics Volume 13 Issue 7 Version 1.0 Year 2013 Type: Double Blind Peer Reviewed International Research Journal Publisher: Global Journals Inc. (USA) Online ISSN: 2249-4596 & Print ISSN: 0975-5861 Review of Magnetic Levitation (MAGLEV): A Technology to Propel Vehicles with Magnets By Monika Yadav, Nivritti Mehta, Aman Gupta, Akshay Chaudhary & D. V. Mahindru SRMGPC, India Abstract - The term “Levitation” refers to a class of technologies that uses magnetic levitation to propel vehicles with magnets rather than with wheels, axles and bearings. Maglev (derived from magnetic levitation) uses magnetic levitation to propel vehicles. With maglev, a vehicle is levitated a short distance away from a “guide way” using magnets to create both lift and thrust. High-speed maglev trains promise dramatic improvements for human travel widespread adoption occurs. Maglev trains move more smoothly and somewhat more quietly than wheeled mass transit systems. Their nonreliance on friction means that acceleration and deceleration can surpass that of wheeled transports, and they are unaffected by weather. The power needed for levitation is typically not a large percentage of the overall energy consumption. Most of the power is used to overcome air resistance (drag). Although conventional wheeled transportation can go very fast, maglev allows routine use of higher top speeds than conventional rail, and this type holds the speed record for rail transportation. Vacuum tube train systems might hypothetically allow maglev trains to attain speeds in a different order of magnitude, but no such tracks have ever been built. Compared to conventional wheeled trains, differences in construction affect the economics of maglev trains.
    [Show full text]
  • Introduction & Overview of Magnetic Levitation (MAGLEV) Train System
    Volume 3, Issue 2, February – 2018 International Journal of Innovative Science and Research Technology ISSN No:-2456 –2165 Introduction & Overview of Magnetic Levitation (MAGLEV) Train System Mr. Abhijeet T. Tambe1 Prof. Dipak S. Patil2 Mechanical Department Mechanical Department Loknete Gopinathji Munde Institute of Engineering Loknete Gopinathji Munde Institute of Engineering Education & Research Education & Research Nashik, India Nashik, India Mr. Sanjay S. Avhad3 Mechanical Department Loknete Gopinathji Munde Institute of Engineering Education & Research Nashik, India Abstract - In this paper, we will discuss about Basics of I. INTRODUCTION magnetic levitation train system , its components and working. A German inventor named “Alfred Zehden” was Basically, the MAGLEV train stands for magnetic levitation awarded by United States Patent for a linear motor propelled train and is a system of high speed transportation as compared train. The inventor was awarded U.S. Patent 782,312 on 14 to conventional train system. February 1905 and U.S. Patent RE 12,700 on 21 August The term “MAGLEV” refers not only to the vehicles 1907. An Electromagnetic transportation system was but to the railway system as well specially design for magnetic discovered and developed in 1907 by F.S. Smith. In levitation and propulsion. The important concept of this system between 1937 & 1941 Herman Kemper was awarded by is to generate magnetic field obtained by using either serious of German patents for magnetic levitation train permanent magnets or electromagnets. As compared to propelled by linear motors. conventional train, maglev train system has no moving parts, the train travels along its guideway of magnets which controls Maglev is derived from magnetic levitation which means the train stability and speed therefore the maglev train are to lift a vehicle without any mechanical support with the quiter and smoother than conventional trains and have the help of magnetic field generated by either permanent potential for much higher speed.
    [Show full text]
  • Analytical Analysis of Magnetic Levitation Systems with Harmonic Voltage Input
    actuators Article Analytical Analysis of Magnetic Levitation Systems with Harmonic Voltage Input Serguei Maximov 1,† , Felipe Gonzalez-Montañez 2,† , Rafael Escarela-Perez 2,*,† , Juan Carlos Olivares-Galvan 2,† and Hector Ascencion-Mestiza 1,† 1 Posgrado en Eléctrica, Tecnológico Nacional de México, Instituto Tecnológico de Morelia, Morelia C.P. 58120, Mexico; [email protected] (S.M.); [email protected] (H.A.-M.) 2 Departamento de Enérgia, Universidad Autónoma Metropolitana Azcapotzalco, Ciudad de México C.P. 02200, Mexico; [email protected] (F.G.-M.); [email protected] (J.C.O.-G.) * Correspondence: [email protected] † These authors contributed equally to this work. Received: 30 July 2020; Accepted: 9 September 2020; Published: 11 September 2020 Abstract: In this paper, a new analytical method using Lagrange equations for the analysis of magnetic levitation (MagLev) systems is proposed, using Thomson’s jumping ring experiment. The method establishes the dependence of the primary and induced currents, and also the equilibrium height of the levitating object on the input voltage through the mutual inductance of the system. The mutual inductance is calculated in two ways: (i) by employing analytical formula; (ii) through an improved semi-empirical formula based on both measurements and analytical results. The obtained MagLev model was analyzed both analytically and numerically. Analytical solutions to the resulting equations were found for the case of a dynamic equilibrium. The numerical results obtained for the dynamical model under transient operation show a close correspondence with the experimental results. The good precision of the analytical and numerical results demonstrates that the developed method can be effectively implemented.
    [Show full text]
  • Unit VI Superconductivity JIT Nashik Contents
    Unit VI Superconductivity JIT Nashik Contents 1 Superconductivity 1 1.1 Classification ............................................. 1 1.2 Elementary properties of superconductors ............................... 2 1.2.1 Zero electrical DC resistance ................................. 2 1.2.2 Superconducting phase transition ............................... 3 1.2.3 Meissner effect ........................................ 3 1.2.4 London moment ....................................... 4 1.3 History of superconductivity ...................................... 4 1.3.1 London theory ........................................ 5 1.3.2 Conventional theories (1950s) ................................ 5 1.3.3 Further history ........................................ 5 1.4 High-temperature superconductivity .................................. 6 1.5 Applications .............................................. 6 1.6 Nobel Prizes for superconductivity .................................. 7 1.7 See also ................................................ 7 1.8 References ............................................... 8 1.9 Further reading ............................................ 10 1.10 External links ............................................. 10 2 Meissner effect 11 2.1 Explanation .............................................. 11 2.2 Perfect diamagnetism ......................................... 12 2.3 Consequences ............................................. 12 2.4 Paradigm for the Higgs mechanism .................................. 12 2.5 See also ...............................................
    [Show full text]
  • Understanding Stable Levitation of Superconductors from Intermediate Electromagnetics A
    Understanding stable levitation of superconductors from intermediate electromagnetics A. Badía-Majósa͒ Departamento de Física de la Materia Condensada-I.C.M.A., C.P.S.U.Z., María de Luna 1, E-50018 Zaragoza, Spain ͑Received 15 February 2006; accepted 28 July 2006͒ Levitation experiments with superconductors in the Meissner state are hindered by low stability except for specifically designed configurations. In contrast, magnetic force experiments with strongly pinned superconductors and permanent magnets display high stability, allowing the demonstration of striking effects, such as lateral or inverted levitation. These facts are explained by using a variational theory. Illustrations based on calculated magnetic field lines for various configurations are presented. They provide a qualitative physical understanding of the stability features. © 2006 American Association of Physics Teachers. ͓DOI: 10.1119/1.2338548͔ I. INTRODUCTION A. Type-I superconductors Levitation experiments based on the repulsive ͑or attrac- We begin with the definition of the electric current density tive͒ force between permanent magnets and superconductors for conducting media are common. Almost everyone is fascinated and stimulated J = nqv, ͑1͒ by the observation of floating objects. When the setup in- cludes a high pinning ͑or high critical current͒ supercon- where n is the volume density of the charge carriers, q their ductor, the possibilities of lifting moderate weights and dis- effective charge, and v their velocity. If the underlying ma- playing lateral or inverted levitation are even more attractive. terial is such that charges can move without friction, New- Recent developments of vehicles capable of supporting sev- ton’s second law gives eral passengers1 have increased the interest in this topic.
    [Show full text]
  • Effect of Hyperloop Technologies on the Electric Grid and Transportation Energy
    Effect of Hyperloop Technologies on the Electric Grid and Transportation Energy January 2021 United States Department of Energy Washington, DC 20585 Department of Energy |January 2021 Disclaimer This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof. Department of Energy |January 2021 [ This page is intentionally left blank] Effect of Hyperloop Technologies on Electric Grid and Transportation Energy | Page i Department of Energy |January 2021 Executive Summary Hyperloop technology, initially proposed in 2013 as an innovative means for intermediate- range or intercity travel, is now being developed by several companies. Proponents point to potential benefits for both passenger travel and freight transport, including time-savings, convenience, quality of service and, in some cases, increased energy efficiency. Because the system is powered by electricity, its interface with the grid may require strategies that include energy storage. The added infrastructure, in some cases, may present opportunities for grid- wide system benefits from integrating hyperloop systems with variable energy resources.
    [Show full text]