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91-479: The design superseded the maglev transport system at Birmingham Airport which was, at the time, the world’s only commercial maglev system. The technology was used for the new AirRail Link on the existing maglev guideway to replace the previous system and temporary bus-service shuttle that had been operating in the meantime. The automated people mover systems are based on cable -propelled technology. The manufacturer claims distances up to 4 km (2.5 mi) and

182-500: A maglev train accident occurred in Lathen, killing 23 people. It was found to have been caused by human error in implementing safety checks. From 2006 no passengers were carried. At the end of 2011 the operation licence expired and was not renewed, and in early 2012 demolition permission was given for its facilities, including the track and factory. In March 2021 it was reported the CRRC

273-868: A 110 kilometres per hour (68 mph) operating speed. Two more stages are planned of 9.7 kilometres (6 mi) and 37.4 kilometres (23.2 mi). Once completed it will become a circular line. It was shut down in September 2023. Transport System Bögl (TSB) is a driverless maglev system developed by the German construction company Max Bögl since 2010. Its primary intended use is for short to medium distances (up to 30 km) and speeds up to 150 km/h for uses such as airport shuttles . The company has been doing test runs on an 820-meter-long test track at their headquarters in Sengenthal , Upper Palatinate , Germany , since 2012 clocking over 100,000 tests covering

364-541: A 30 percent increase in traction efficiency and a 60 percent increase in speed over the stock in use on the line since. The vehicles entered service in July 2021 with a top speed of 140 km/h (87 mph). CRRC Zhuzhou Locomotive said in April 2020 it is developing a model capable of 200 km/h (120 mph). There are two competing efforts for high-speed maglev systems, i.e., 300–620 km/h (190–390 mph). In

455-502: A 60-metre ramp which was later extended to 980 metres. From the late 1970s to the 1980s five prototypes of cars were built that received designations from TP-01 (ТП-01) to TP-05 (ТП-05). The early cars were supposed to reach the speed up to 100 kilometres per hour (62 mph). The construction of a maglev track using the technology from Ramenskoye started in Armenian SSR in 1987 and was planned to be completed in 1991. The track

546-471: A 90-foot test track in Johnson's basement "absolutely noiseless[ly] and without the least vibration." A series of German patents for magnetic levitation trains propelled by linear motors were awarded to Hermann Kemper between 1937 and 1941. An early maglev train was described in U.S. patent 3,158,765 , "Magnetic system of transportation", by G. R. Polgreen on 25 August 1959. The first use of "maglev" in

637-640: A 908 metres (2,979 ft) track was opened in Hamburg for the first International Transportation Exhibition (IVA 79). Interest was sufficient that operations were extended three months after the exhibition finished, having carried more than 50,000 passengers. It was reassembled in Kassel in 1980. In 1979 the USSR town of Ramenskoye ( Moscow oblast ) built an experimental test site for running experiments with cars on magnetic suspension. The test site consisted of

728-473: A German maglev company, had a test track in Emsland with a total length of 31.5 kilometres (19.6 mi). The single-track line ran between Dörpen and Lathen with turning loops at each end. The trains regularly ran at up to 420 kilometres per hour (260 mph). Paying passengers were carried as part of the testing process. The construction of the test facility began in 1980 and finished in 1984. In 2006,

819-472: A United States patent was in "Magnetic levitation guidance system" by Canadian Patents and Development Limited . In 1912 French-American inventor Émile Bachelet demonstrated a model train with electromagnetic levitation and propulsion in Mount Vernon, New York. Bachelet's first related patent, U.S. patent 1,020,942 was granted in 1912. The electromagnetic propulsion was by attraction of iron in

910-401: A central control room; there are no drivers, conductors or operators on-board. The evacuation system is based on an independent stationary diesel emergency drive that would pull a stranded train back to the station, eliminating the need for an emergency walkway. Trains like these can be also used for different purposes, such as moving trailers and barge loaders. The automated people mover uses

1001-582: A concern at low speeds, and is one of the reasons why JR abandoned a purely repulsive system and adopted the sidewall levitation system. At higher speeds other modes of drag dominate. The drag force can be used to the electrodynamic system's advantage, however, as it creates a varying force in the rails that can be used as a reactionary system to drive the train, without the need for a separate reaction plate, as in most linear motor systems. Laithwaite led development of such "traverse-flux" systems at his Imperial College laboratory. Alternatively, propulsion coils on

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1092-412: A configuration where the lift is neutralized. Magnetic levitation is used for maglev trains, contactless melting , magnetic bearings , and for product display purposes. Magnetic materials and systems are able to attract or repel each other with a force dependent on the magnetic field and the area of the magnets. For example, the simplest example of lift would be a simple dipole magnet positioned in

1183-408: A diamagnet, due to the eddy currents generated in the conductor. Since the eddy currents create their own fields which oppose the magnetic field, the conductive object is repelled from the electromagnet, and most of the field lines of the magnetic field will no longer penetrate the conductive object. This effect requires non-ferromagnetic but highly conductive materials like aluminium or copper, as

1274-589: A distance of over 65,000 km as of 2018. In 2018 Max Bögl signed a joint venture with the Chinese company Chengdu Xinzhu Road & Bridge Machinery Co. with the Chinese partner given exclusive rights of production and marketing for the system in China. The joint venture constructed a 3.5 km (2.2 mi) demonstration line near Chengdu , China, and two vehicles were airlifted there in June, 2020. In February 2021

1365-527: A ferromagnetic rail. The magnetic flux crosses the rail in a direction transversal to the first axis and creates a closed-loop on the U-shaped profile. This configuration generates a stable equilibrium along the first axis that maintains the rail centered on the flux crossing point (minimum magnetic reluctance) and allows to bear a load magnetically. On the other axis, the system is constrained and centered by mechanical means, such as wheels. The attraction from

1456-441: A fixed-strength magnet decreases with increased distance, and increases at closer distances. This is unstable. For a stable system, the opposite is needed: variations from a stable position should push it back to the target position. Stable magnetic levitation can be achieved by measuring the position and speed of the object being levitated, and using a feedback loop which continuously adjusts one or more electromagnets to correct

1547-612: A high-speed maglev system. Instead, overcoming drag takes the most energy. Vactrain technology has been proposed as a means to overcome this limitation. Despite over a century of research and development, there are only six operational maglev trains today — three in China, two in South Korea, and one in Japan. In the late 1940s, the British electrical engineer Eric Laithwaite , a professor at Imperial College London , developed

1638-524: A levitation system uses negative feedback to maintain its equilibrium by damping out any oscillations that may occur, it has achieved dynamic stability. For the case of a static magnetic field, the magnetic force is a conservative force and therefore can exhibit no built-in damping. In practice many of the levitation schemes are marginally stable and, when non-idealities of physical systems are considered, result in negative damping. This negative damping gives rise to exponentially growing oscillations around

1729-599: A new high-speed maglev line, the Chuo Shinkansen , started in 2014. It is being built by extending the SCMaglev test track in Yamanashi in both directions. The completion date is unknown, with the estimate of 2027 no longer possible following a local governmental rejection of a construction permit. Transrapid 05 was the first maglev train with longstator propulsion licensed for passenger transportation. In 1979,

1820-416: A peak passenger flow of up to 7,000 pphpd (people per hour per direction) are possible. In a cable-propelled automated people mover system, a central station powers the system, and therefore the train has no on-board drive engines, gearboxes or brakes. A fixed grip assembly connects the train to the cable. The cable propels , accelerates , and decelerates the train. The system operation is monitored from

1911-525: A self-supporting steel guideway. It is a light steel guideway, which is possible because of the use of lighter trains. The track consists of an I-beam which forms the running and guiding surface. The guideway superstructure is a steel framework construction. The guideway does not require heating in harsh winter conditions. Steel adapters between the steel truss guideway and the concrete columns allow height adjustments to compensate for ground settlements. The track can span more than 67 m (220 ft). Because

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2002-551: A single car along a short section of track at the fairgrounds. It was removed after the fair. It was shown at the Aoi Expo in 1987 and is now on static display at Okazaki Minami Park. In 1993, South Korea completed the development of its own maglev train, shown off at the Taejŏn Expo '93 , which was developed further into a full-fledged maglev capable of travelling up to 110 kilometres per hour (68 mph) in 2006. This final model

2093-557: A transfer to the Seoul Metropolitan Subway at AREX 's Incheon International Airport Station and is offered free of charge to anyone to ride, operating between 9   am and 6   pm with 15-minute intervals. The maglev system was co-developed by the South Korea Institute of Machinery and Materials (KIMM) and Hyundai Rotem . It is 6.1 kilometres (3.8 mi) long, with six stations and

2184-504: A vehicle on the Chinese test track hit a top speed of 169 km/h (105 mph). According to the International Maglev Board there are at least four maglev research programmes underway in China at: Southwest Jiaotong University (Chengdu), Tongji University (Shanghai), CRRC Tangshan-Changchun Railway Vehicle Co. , and Chengdu Aircraft Industry Group . The latest high-speed prototype , unveiled in July 2021,

2275-804: Is HSST (and its descendant, the Linimo line) by Japan Airlines and the other, which is more well known, is SCMaglev by the Central Japan Railway Company . The development of the latter started in 1969. The first successful SCMaglev run was made on a short track at the Japanese National Railways ' (JNR's) Railway Technical Research Institute in 1972. Maglev trains on the Miyazaki test track (a later, 7 km long test track) regularly hit 517 kilometres per hour (321 mph) by 1979. After an accident destroyed

2366-417: Is a method by which an object is suspended with no support other than magnetic fields . Magnetic force is used to counteract the effects of the gravitational force and any other forces. The two primary issues involved in magnetic levitation are lifting forces : providing an upward force sufficient to counteract gravity, and stability : ensuring that the system does not spontaneously slide or flip into

2457-565: Is a system of rail transport whose rolling stock is levitated by electromagnets rather than rolled on wheels, eliminating rolling resistance . Compared to conventional railways, maglev trains can have higher top speeds, superior acceleration and deceleration, lower maintenance costs, improved gradient handling, and lower noise. However, they are more expensive to build, cannot use existing infrastructure, and use more energy at high speeds. Maglev trains have set several speed records . The train speed record of 603 km/h (375 mph)

2548-529: Is comparable to the Double Shuttle system in terms of capacity and frequency (headway). Either each train has its own haul rope or both trains are attached to the same haul rope depending on the application requirements (station configuration, system length, etc.). This system creates a circular train flow where more than one train moves in the same direction. The principle of this system is based on several rope loops which adjoin and overlap each other in

2639-402: Is generally quite a weak effect in most materials, although superconductors exhibit a strong effect. A substance that is diamagnetic repels a magnetic field. All materials have diamagnetic properties, but the effect is very weak, and is usually overcome by the object's paramagnetic or ferromagnetic properties, which act in the opposite manner. Any material in which the diamagnetic component

2730-512: Is inter-operable with steel rail tracks and would permit maglev vehicles and conventional trains to operate on the same tracks. MAN in Germany also designed a maglev system that worked with conventional rails, but it was never fully developed. Each implementation of the magnetic levitation principle for train-type travel involves advantages and disadvantages. Magnetic levitation Magnetic levitation ( maglev ) or magnetic suspension

2821-736: Is now on display at Railworld in Peterborough, together with the RTV31 hover train vehicle. Another is on display at the National Railway Museum in York. Several favourable conditions existed when the link was built: After the system closed in 1995, the original guideway lay dormant until 2003, when a replacement cable-hauled system, the AirRail Link Cable Liner people mover, was opened. Transrapid,

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2912-535: Is produced either by superconducting magnets (as in JR–Maglev) or by an array of permanent magnets (as in Inductrack ). The repulsive and attractive force in the track is created by an induced magnetic field in wires or other conducting strips in the track. A major advantage of EDS maglev systems is that they are dynamically stable—changes in distance between the track and the magnets creates strong forces to return

3003-476: Is sometimes required. If one moves a base made of a very good electrical conductor such as copper , aluminium , or silver close to a magnet, an ( eddy ) current will be induced in the conductor that will oppose the changes in the field and create an opposite field that will repel the magnet ( Lenz's law ). At a sufficiently high rate of movement, a suspended magnet will levitate on the metal, or vice versa with suspended metal. Litz wire made of wire thinner than

3094-426: Is stronger will be repelled by a magnet. Diamagnetic levitation can be used to levitate very light pieces of pyrolytic graphite or bismuth above a moderately strong permanent magnet. As water is predominantly diamagnetic, this technique has been used to levitate water droplets and even live animals, such as a grasshopper, frog and a mouse. However, the magnetic fields required for this are very high, typically in

3185-477: Is the permeability of the vacuum. Earnshaw's theorem proves that using only paramagnetic materials (such as ferromagnetic iron) it is impossible for a static system to stably levitate against gravity. For example, the simplest example of lift with two simple dipole magnets repelling is highly unstable, since the top magnet can slide sideways or flip over, and it turns out that no configuration of magnets can produce stability. However, servomechanisms ,

3276-581: Is the simplest configuration, with one train operating in both directions on one guideway track. The "Double Shuttle" configuration features two independent shuttle systems operating side by side on a double guideway track, each with its own haul rope and drive machinery. If one shuttle system fails or is closed for maintenance, the other system may continue to operate. This configuration is designed for system lengths up to 3 km (1.8 mi) and may have several intermediate stations. The frequency and passenger capacity of both shuttle systems depends largely on

3367-424: Is to more than triple the lift force. Using two opposed Halbach arrays increases the field even further. Halbach arrays are also well-suited to magnetic levitation and stabilisation of gyroscopes and spindles of electric motors and generators . A conductor can be levitated above an electromagnet (or vice versa) with an alternating current flowing through it. This causes any regular conductor to behave like

3458-465: Is typically arranged on a series of C-shaped arms, with the upper portion of the arm attached to the vehicle, and the lower inside edge containing the magnets. The rail is situated inside the C, between the upper and lower edges. Magnetic attraction varies inversely with the square of distance, so minor changes in distance between the magnets and the rail produce greatly varying forces. These changes in force are dynamically unstable—a slight divergence from

3549-414: Is typically the case with electrodynamic suspension maglev trains. Aerodynamic factors may also play a role in the levitation of such trains. The two main types of maglev technology are: In electromagnetic suspension (EMS) systems, the train levitates by attraction to a ferromagnetic (usually steel) rail while electromagnets , attached to the train, are oriented toward the rail from below. The system

3640-664: The British Rail Research Division in Derby , along with teams at several civil engineering firms, the "transverse-flux" system was developed into a working system. The first commercial maglev people mover was simply called " MAGLEV " and officially opened in 1984 near Birmingham , England. It operated on an elevated 600 metres (2,000 ft) section of monorail track between Birmingham Airport and Birmingham International railway station , running at speeds up to 42 kilometres per hour (26 mph). The system

3731-565: The Throgs Neck Bridge , James Powell , a researcher at Brookhaven National Laboratory (BNL), thought of using magnetically levitated transportation. Powell and BNL colleague Gordon Danby worked out a maglev concept using static magnets mounted on a moving vehicle to induce electrodynamic lifting and stabilizing forces in specially shaped loops, such as figure-of-8 coils on a guideway. These were patented in 1968–1969. Japan operates two independently developed maglev trains. One

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3822-505: The Tracked Hovercraft RTV-31, based near Cambridge, UK, although the project was cancelled in 1973. The linear motor was naturally suited to use with maglev systems as well. In the early 1970s, Laithwaite discovered a new arrangement of magnets, the magnetic river , that allowed a single linear motor to produce both lift and forward thrust, allowing a maglev system to be built with a single set of magnets. Working at

3913-420: The skin depth for the frequencies seen by the metal works much more efficiently than solid conductors. Figure-8 coils can be used to keep something aligned. An especially technologically interesting case of this comes when one uses a Halbach array instead of a single-pole permanent magnet, as this almost doubles the field strength, which in turn almost doubles the strength of the eddy currents. The net effect

4004-470: The z -direction of solenoid magnet: Superconductors may be considered perfect diamagnets , and completely expel magnetic fields due to the Meissner effect when the superconductivity initially forms; thus superconducting levitation can be considered a particular instance of diamagnetic levitation. In a type-II superconductor, the levitation of the magnet is further stabilized due to flux pinning within

4095-492: The amount of lift, a magnetic pressure can be defined. For example, the magnetic pressure of a magnetic field on a superconductor can be calculated by: where P mag {\displaystyle P_{\text{mag}}} is the force per unit area in pascals , B {\displaystyle B} is the magnetic field just above the superconductor in teslas , and μ 0 {\displaystyle \mu _{0}} = 4π × 10  N·A

4186-435: The car body and take the form of cavity-sealed tubular steel frames. The design is torsion-free. The vehicle interior is predominantly aluminium, with no heat release. The vehicles are usually manufactured by Swiss cabin manufacturer, CWA Constructions , itself a subsidiary of Doppelmayr Garaventa Group; or Austrian cabin manufacturer, Carvatech. There are three main system configurations in use. The "Single Shuttle" system

4277-414: The distance of 30.5 kilometres (19 mi) in just over 8   minutes. Different maglev systems achieve levitation in different ways, which broadly fall into two categories: electromagnetic suspension (EMS) and electrodynamic suspension (EDS) . Propulsion is typically provided by a linear motor . The power needed for levitation is typically not a large percentage of the overall energy consumption of

4368-457: The downside, the dynamic instability demands fine track tolerances, which can offset this advantage. Eric Laithwaite was concerned that to meet required tolerances, the gap between magnets and rail would have to be increased to the point where the magnets would be unreasonably large. In practice, this problem was addressed through improved feedback systems, which support the required tolerances. Air gap and energy efficiency can be improved by using

4459-499: The equilibrium point. Earnshaw's theorem proved conclusively that it is not possible to levitate stably using only static, macroscopic, paramagnetic fields. The forces acting on any paramagnetic object in any combinations of gravitational , electrostatic , and magnetostatic fields will make the object's position, at best, unstable along at least one axis, and it can be in unstable equilibrium along all axes. However, several possibilities exist to make levitation viable, for example,

4550-521: The ferromagnetic ones are also strongly attracted to the electromagnet (although at high frequencies the field can still be expelled) and tend to have a higher resistivity giving lower eddy currents. Again, litz wire gives the best results. The effect can be used for stunts such as levitating a telephone book by concealing an aluminium plate within it. At high frequencies (a few tens of kilohertz or so) and kilowatt powers small quantities of metals can be levitated and melted using levitation melting without

4641-537: The field exerted by magnets on the train and the applied field creates a force moving the train forward. The term "maglev" refers not only to the vehicles, but to the railway system as well, specifically designed for magnetic levitation and propulsion. All operational implementations of maglev technology make minimal use of wheeled train technology and are not compatible with conventional rail tracks . Because they cannot share existing infrastructure, maglev systems must be designed as standalone systems. The SPM maglev system

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4732-425: The first full-size working model of the linear induction motor . He became professor of heavy electrical engineering at Imperial College in 1964, where he continued his successful development of the linear motor. Since linear motors do not require physical contact between the vehicle and guideway, they became a common fixture on advanced transportation systems in the 1960s and 1970s. Laithwaite joined one such project,

4823-462: The guideway and the train exert a magnetic field, and the train is levitated by the repulsive and attractive force between these magnetic fields. In some configurations, the train can be levitated only by repulsive force. In the early stages of maglev development at the Miyazaki test track, a purely repulsive system was used instead of the later repulsive and attractive EDS system. The magnetic field

4914-418: The guideway are used to exert a force on the magnets in the train and make the train move forward. The propulsion coils that exert a force on the train are effectively a linear motor: an alternating current through the coils generates a continuously varying magnetic field that moves forward along the track. The frequency of the alternating current is synchronized to match the speed of the train. The offset between

5005-518: The guideway superstructure is a steel framework construction and do not have a solid track base, platform screen doors are used at stations on the system. The trains are bidirectional. The car is a self-supporting lightweight design with extruded aluminium box-type profile sections. The integral monocoque structure is bolted and riveted and joint connections are aluminium castings. The aluminium sections are made of high-grade, corrosion-resistant alloy . The undercarriage supports are integrated into

5096-459: The length of the system, and the number of intermediate stations. The passenger capacity additionally depends on the capacity of the train. In this system, only one guideway enters each end station, but movable switches direct trains onto dual tracks between stations so they can pass one another en route. The bypass must be located approximately in the middle of two terminal end stations, and can form part of an intermediate station. This configuration

5187-450: The levitation of a permanent magnet can even be stabilized by the small diamagnetism of water in human fingers. Diamagnetism is the property of an object which causes it to create a magnetic field in opposition to an externally applied magnetic field, thus causing the material to be repelled by magnetic fields. Diamagnetic materials cause lines of magnetic flux to curve away from the material. Specifically, an external magnetic field alters

5278-613: The maglev theme was continued by the Engineering Research Center "TEMP" (ИНЦ "ТЭМП") this time by the order from the Moscow government . The project was named V250 (В250). The idea was to build a high-speed maglev train to connect Moscow to the Sheremetyevo airport . The train would consist of 64-seater cars and run at speeds up to 250 kilometres per hour (160 mph). In 1993, due to the financial crisis ,

5369-496: The magnetic field's unstable equilibrium point, inevitably causing the levitating object to be ejected from the magnetic field. Dynamic stability on the other hand, can be achieved by spinning a permanent magnet having poles slightly off the rotation plane (called tilt) in constant speed within a range which can hold another dipole magnet in the air. For the magnetic levitation scheme to be stable, negative feedback from an external control system can be also used to add damping to

5460-409: The magnetic fields of another dipole magnet, oriented with like poles facing each other, so that the force between magnets repels the two magnets. Essentially all types of magnets have been used to generate lift for magnetic levitation; permanent magnets , electromagnets , ferromagnetism , diamagnetism , superconducting magnets , and magnetism due to induced currents in conductors. To calculate

5551-500: The magnets above the other. Another geometry is where the magnets are attracted, but prevented from touching by a tensile member, such as a string or cable. Another example is the Zippe-type centrifuge where a cylinder is suspended under an attractive magnet, and stabilized by a needle bearing from below. Another configuration consists of an array of permanent magnets installed in a ferromagnetic U-shaped profile and coupled with

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5642-493: The object cuts a beam of light or Hall effect sensor method is used to measure the position of the object. The electromagnet is above the object being levitated; the electromagnet is turned off whenever the object gets too close, and turned back on when it falls further away. Such a simple system is not very robust; far more effective control systems exist, but this illustrates the basic idea. EMS magnetic levitation trains are based on this kind of levitation: The train wraps around

5733-450: The object's motion, thus forming a servomechanism . Many systems use magnetic attraction pulling upward against gravity for these kinds of systems as this gives some inherent lateral stability, but some use a combination of magnetic attraction and magnetic repulsion to push upward. Either system represents examples of ElectroMagnetic Suspension (EMS). For a very simple example, some tabletop levitation demonstrations use this principle, and

5824-472: The optimum position tends to grow, requiring sophisticated feedback systems to maintain a constant distance from the track, (approximately 15 millimetres [0.59 in]). The major advantage to suspended maglev systems is that they work at all speeds, unlike electrodynamic systems, which only work at a minimum speed of about 30 kilometres per hour (19 mph). This eliminates the need for a separate low-speed suspension system, and can simplify track layout. On

5915-414: The orbital velocity of electrons around their nuclei, thus changing the magnetic dipole moment. According to Lenz's law, this opposes the external field. Diamagnets are materials with a magnetic permeability less than μ 0 (a relative permeability less than 1). Consequently, diamagnetism is a form of magnetism that is only exhibited by a substance in the presence of an externally applied magnetic field. It

6006-474: The other axes can be stabilized using ferromagnetism. The primary ones used in maglev trains are servo-stabilized electromagnetic suspension (EMS), electrodynamic suspension (EDS). With a small amount of mechanical constraint for stability, achieving pseudo-levitation is a relatively straightforward process. If two magnets are mechanically constrained along a single axis, for example, and arranged to repel each other strongly, this will act to levitate one of

6097-552: The passengers. Switches installed at the end stations will guide the train from one lane of the double lane track over to a single guideway in the end stations. During the station stop the switch will be repositioned that the train can leave the station at the other lane of the double lane track. For the functionality of the Pinched Loop concept the stations spans have to be approximately equidistant from each other. Maglev Maglev (derived from magnetic levitation )

6188-501: The project was abandoned. However, from 1999 the "TEMP" research center had been participating as a co-developer in the creation of the linear motors for the Moscow Monorail system. The world's first commercial maglev system was a low-speed maglev shuttle that ran between the airport terminal of Birmingham International Airport and the nearby Birmingham International railway station between 1984 and 1995. Its track length

6279-830: The public imagination, "maglev" often evokes the concept of an elevated monorail track with a linear motor . Maglev systems may be monorail or dual rail—the SCMaglev MLX01 for instance uses a trench-like track—and not all monorail trains are maglevs. Some railway transport systems incorporate linear motors but use electromagnetism only for propulsion , without levitating the vehicle. Such trains have wheels and are not maglevs. Maglev tracks, monorail or not, can also be constructed at grade or underground in tunnels. Conversely, non-maglev tracks, monorail or not, can be elevated or underground too. Some maglev trains do incorporate wheels and function like linear motor-propelled wheeled vehicles at slower speeds but levitate at higher speeds. This

6370-527: The range of 16 teslas , and therefore create significant problems if ferromagnetic materials are nearby. Operation of this electromagnet used in the frog levitation experiment required 4 MW (4000000 watts) of power. The minimum criterion for diamagnetic levitation is B d B d z = μ 0 ρ g χ {\displaystyle B{\frac {dB}{dz}}=\mu _{0}\,\rho \,{\frac {g}{\chi }}} , where: Assuming ideal conditions along

6461-489: The registration of Bachelet Levitated Railway Syndicate Limited July 9 in London, just weeks before the start of WWI. Bachelet's second related patent, U.S. patent 1,020,943 granted the same day as the first, had the levitation electromagnets in the train and the track was aluminum plate. In the patent he stated that this was a much cheaper construction, but he did not demonstrate it. In 1959, while delayed in traffic on

6552-626: The risk of the metal being contaminated by the crucible. One source of oscillating magnetic field that is used is the linear induction motor . This can be used to levitate as well as provide propulsion. Earnshaw's theorem does not apply to diamagnets . These behave in the opposite manner to normal magnets owing to their relative permeability of μ r < 1 (i.e. negative magnetic susceptibility ). Diamagnetic levitation can be inherently stable. A permanent magnet can be stably suspended by various configurations of strong permanent magnets and strong diamagnets. When using superconducting magnets,

6643-458: The socalled "Hybrid Electromagnetic Suspension (H-EMS)", where the main levitation force is generated by permanent magnets, while the electromagnet controls the air gap, what is called electropermanent magnets . Ideally it would take negligible power to stabilize the suspension and in practice the power requirement is less than it would be if the entire suspension force were provided by electromagnets alone. In electrodynamic suspension (EDS), both

6734-459: The stations. Every haul rope loop is supplied with its own drive and return machinery. In every station each vehicle of the train has to be disconnected from the current haul rope to the next haul rope in order to continue the circular and synchronized train flow. The haul rope loop change may occur only when all the trains are positioned at the standard stop position in the stations and are standstill and will be carried out during boarding/alighting of

6825-406: The system to its original position. In addition, the attractive force varies in the opposite manner, providing the same adjustment effects. No active feedback control is needed. However, at slow speeds, the current induced in these coils and the resultant magnetic flux is not large enough to levitate the train. For this reason, the train must have wheels or some other form of landing gear to support

6916-419: The system. This can be accomplished in a number of ways: For successful levitation and control of all 6 axes (degrees of freedom; 3 translational and 3 rotational) a combination of permanent magnets and electromagnets or diamagnets or superconductors as well as attractive and repulsive fields can be used. From Earnshaw's theorem at least one stable axis must be present for the system to levitate successfully, but

7007-439: The track, and is pulled upward from below. The servo controls keep it safely at a constant distance from the track. These schemes work due to repulsion due to Lenz's law . When a conductor is presented with a time-varying magnetic field, electrical currents are set up in the conductor which create a magnetic field that causes a repulsive effect. These kinds of systems typically show an inherent stability, although extra damping

7098-494: The train by direct current solenoids spaced along the track. The electromagnetic levitation was due to repulsion of the aluminum base plate of the train by the pulsating current electromagnets under the track. The pulses were generated by Bachelet's own Synchronizing-interrupter U.S. patent 986,039 supplied with 220 VAC. As the train moved it switched power to the section of track that it was on. Bachelet went on to demonstrate his model in London, England in 1914, which resulted in

7189-456: The train until it reaches take-off speed. Since a train may stop at any location, due to equipment problems for instance, the entire track must be able to support both low- and high-speed operation. Another downside is that the EDS system naturally creates a field in the track in front and to the rear of the lift magnets, which acts against the magnets and creates magnetic drag. This is generally only

7280-489: The train, a new design was selected. In Okazaki , Japan (1987), the SCMaglev was used for test rides at the Okazaki exhibition. Tests in Miyazaki continued throughout the 1980s, before transferring to a far longer test track, 20 kilometres (12 mi) long, in Yamanashi in 1997. The track has since been extended to almost 43 kilometres (27 mi). The 603 kilometres per hour (375 mph) world speed record for crewed trains

7371-423: The use of diamagnetic materials, superconduction , or systems involving eddy currents allow stability to be achieved. In some cases the lifting force is provided by magnetic repulsion, but stability is provided by a mechanical support bearing little load. This is termed pseudo-levitation . Static stability means that any small displacement away from a stable equilibrium causes a net force to push it back to

7462-409: The use of electronic stabilization or diamagnetic materials (since relative magnetic permeability is less than one ); it can be shown that diamagnetic materials are stable along at least one axis, and can be stable along all axes. Conductors can have a relative permeability to alternating magnetic fields of below one, so some configurations using simple AC-driven electromagnets are self stable. When

7553-411: Was 600 metres (2,000 ft), and trains levitated at an altitude of 15 millimetres [0.59 in], levitated by electromagnets, and propelled with linear induction motors. It operated for 11 years and was initially very popular with passengers, but obsolescence problems with the electronic systems made it progressively unreliable as years passed, leading to its closure in 1995. One of the original cars

7644-404: Was awarded U.S. patent 782,312 (14 February 1905) and U.S. patent RE12700 (21 August 1907). In 1907, another early electromagnetic transportation system was developed by F. S. Smith. In 1908, Cleveland mayor Tom L. Johnson filed a patent for a wheel-less "high-speed railway" levitated by an induced magnetic field. Jokingly known as "Greased Lightning," the suspended car operated on

7735-481: Was closed in 1995 due to reliability problems. High-speed transportation patents were granted to various inventors throughout the world. The first relevant patent, U.S. patent 714,851 (2 December 1902), issued to Albert C. Albertson, used magnetic levitation to take part of the weight off of the wheels while using conventional propulsion. Early United States patents for a linear motor propelled train were awarded to German inventor Alfred Zehden . The inventor

7826-654: Was incorporated in the Incheon Airport Maglev which opened on 3 February 2016, making South Korea the world's fourth country to operate its own self-developed maglev after the United Kingdom's Birmingham International Airport, Germany's Berlin M-Bahn , and Japan 's Linimo . It links Incheon International Airport to the Yongyu Station and Leisure Complex on Yeongjong island . It offers

7917-511: Was investigating reviving the Emsland test track. In May 2019 CRRC had unveiled its "CRRC 600" prototype which is designed to reach 600 kilometres per hour (370 mph). In Vancouver, Canada, the HSST-03 by HSST Development Corporation ( Japan Airlines and Sumitomo Corporation ) was exhibited at Expo 86 , and ran on a 400-metre (0.25 mi) test track that provided guests with a ride in

8008-672: Was manufactured by CRRC Qingdao Sifang . Development of the low-to-medium speed systems, that is, 100–200 km/h (62–124 mph), by the CRRC has led to opening lines such as the Changsha Maglev Express in 2016 and the Line S1 in Beijing in 2017. In April 2020 a new model capable of 160 km/h (99 mph) and compatible with the Changsha line completed testing. The vehicle, under development since 2018, has

8099-487: Was set by the experimental Japanese L0 Series maglev in 2015. From 2002 until 2021, the record for the highest operational speed of a passenger train of 431 kilometres per hour (268 mph) was held by the Shanghai maglev train , which uses German Transrapid technology. The service connects Shanghai Pudong International Airport and the outskirts of central Pudong , Shanghai . At its historical top speed, it covered

8190-661: Was set there in 2015. Development of HSST started in 1974. In Tsukuba , Japan (1985), the HSST-03 ( Linimo ) became popular at the Tsukuba World Exposition , in spite of its low 30 kilometres per hour (19 mph) top speed. In Saitama , Japan (1988), the HSST-04-1 was revealed at the Saitama exhibition in Kumagaya . Its fastest recorded speed was 300 kilometres per hour (190 mph). Construction of

8281-542: Was supposed to connect the cities of Yerevan and Sevan via the city of Abovyan . The original design speed was 250 kilometres per hour (160 mph) which was later lowered to 180 kilometres per hour (110 mph). However, the Spitak earthquake in 1988 and the First Nagorno-Karabakh War caused the project to freeze. In the end the overpass was only partially constructed. In the early 1990s,

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