maglev vehicles
TRANSCRIPT
MAGLEV VEHICLES
BY NEHA DESHPANDE
VANISHREE DALWAI
2ND SEM E&C, GIT, BELGAUM
Vanishree : contact no. : 2459900 Neha Deshpande: contact no : 2480926
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ABSTRACT
MAGLEV VEHICLES are actually MAGnetically LEVitated
vehicles. Although maglev technology advanced, its basic principles are relatively simple
and readily understood. These are high speed vehicles that are lifted by the magnetic
repulsion, and propelled along an elevated guideway by powerful magnets attached to the
vehicle. It is a contact less, frictionless vehicle, which does not need an engine nor do
they burn fuel. In this paper we are presenting the basic principle involved, its working
and applications. A typical example of M-2000 of Florida corp. has been included. The
applications of maglev are vast and developments in the fields of water trains,
underground & open pit mining, Lexus maglev cars, 2000 mph transcontinental maglev,
inexpensive launch Into Orbit Etc. may be the future.
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INDEX
1) INTRODUCTION……………………………………………………4
2) CONSTRUCTION…………………………………………………...6
3) WORKING…………………………………………………………..7
4) APPLICATIONS……………………………………………………11
5) EXAMPLE …………………………………………………………13
6) ADVANTAGES AND DISADVANTAGES………………………16
7) CONCLUSION……………………………………………………..18
8) FIGURES…………………………………………………………...25
10)REFERENCES……………………………………..……………....27
INDEX (VIDEO FILES)
1) Maglev demo and testing(4min:26secs).. ………………….....4
2) Maglev 2000 of Florida(Passenger and Freight system)….....9
(5min:58secs)
3) Maglev applications(2mins:46secs)………………………….10
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INTRODUCTION
(click on this)
‘Every experiment is new in itself; its failure is an experience’
Maglev has been a dream since the early 1900s. Emile Bachelet proposed to
magnetically levitate trains using attached alternating current (AC) loops above
conducting metal sheets, such as aluminum, on the ground. Other ideas followed, based
on conventional electromagnets and permanent magnets. (Refer fig 1.1 & fig 1.2).
However, all these proposals were impractical. Either power consumption was too great,
or the suspension was unstable, or the weight that could be levitated was too small. [1]
(Refer fig 1.3)
In 1966, Powell and Danby proposed the first practical system for magnetically
levitated transport, using superconducting magnets located on moving vehicles to induce
currents in normal aluminum loops on a guideway. The first patent for a magnetically
levitated vehicle was granted in 1968 to US scientist Gordon Danby and James Powell.
[2]. The maglev vehicles carrying lightweight superconducting magnets that induced
currents in a sequence of ordinary aluminum loops mounted along a guideway are
automatically levitated and stabilized, both vertically and laterally, as they move along
the guideway. The vehicles are magnetically propelled along the guideway by a small AC
current in the guideway. The utility of such levitation is that, in the absence of contact
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between the moving and stationary systems, the friction is eliminated. With such an
arrangement, great speeds could be achieved with very low energy consumption.
The speeds achievable are around 268 miles per hour to over 300 miles per hour.
A second generation maglev system that travels in an evacuated tunnel-- i.e., a vacuum
could potentially travel the 2,800 miles in less than an hour. No ground-based form of
transport and no commercial airplane can do that, or will be able to for some time to
come.
The original Powell-Danby maglev inventions form the basis for the maglev system in
Japan, which is currently being demonstrated in Yamanashi region, Japan. Powell and
Danby have subsequently developed new Maglev inventions that form the basis for their
second generation M-2000 System. The basic principle involved in the maglev vehicles is
the ‘Meissner effect’. It states that “A superconducting material kept in a magnetic field
expels the magnetic flux out of its body when it is cooled below the critical temperature
and thus becomes perfect diamagnet”.
CONSTRUCTION
The vehicle consists of superconducting magnets in built into its base. There is an
aluminium guideway over which the vehicle will be set afloat by magnetic levitation. The
magnetic levitation is brought about by enormous repulsion between two highly powerful
magnetic fields; one produced by the superconducting magnet inside the vehicle, and the
other by the electric currents in the aluminium guideway. (Refer fig 1.4).
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During the motion of the vehicle it is enough if that the part of the guideway over
which the vehicle is located is activated instantaneously. For, this reason the guideway is
formulated in terms of numbers of segments provided with the coils. The flow of currents
could be related to the position and instantaneous speed of the vehicle. The current in the
guideway not only produce the necessary field to levitate the vehicle, but also help in
propelling forward. The vehicle is provided with the retractable wheels. The wheels
serve almost the same purpose as those of an airplane. With the wheels, the vehicles run
on the guideway the way the airplane does during its take off. Once it is levitated in air
the wheels are retracted into the body. While stopping, the wheels are drawn out and the
vehicle slowly settles on the guideway by running over a distance, as an airplane does
while landing. In this Maglev system, which is similar to the one in Japan, the vehicle has
superconductor loops (approximately 600 kilo amp turns). The guideway has aluminum loops at
normal temperature; their loop currents are generated by magnetic induction as vehicle loops
move past them. The induced currents in “figure-8” guideway loops levitate and vertically stabilize
the vehicle. The left and right dipole guideway loops are electrically connected to form a circuit.
Net flux and current in the circuit is zero when the vehicle is centered in the guideway. If the
vehicle moves left from the center, the magnet force develops to push it back to the center. (Refer
fig 1.5)
WORKING
‘An ounce of action is worth a ton of theory’-Friedrich Engels.
Although most people are unfamiliar with maglev technology, its basic principles
are relatively simple and readily understood. Compared to much of the equipment we
already use in our existing transport systems, the hardware employed in maglev systems
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is not as complex and less subject to stress during operation. For example, airplanes are
much more complex than maglev vehicles. Airplanes have highly stressed, high
temperature jet engines, many miles of electrical wiring and hydraulic lines, complex
control systems and so on. In contrast, maglev vehicles based on superconducting
magnets operate with simple coils of superconducting wire and compact cryogenic
coolers. Maglev hardware is commercially available and highly reliable, and operates in a
highly redundant manner with a very large margin of safety. (Refer fig 2.1 & fig 2.2). [3]
SUPERCONDUCTIVITY
Since the main phenomenon for maglev vehicles is Superconductivity, a brief idea
about superconductivity is given below:
Superconductivity:
The phenomenon of zero resistance at low temperatures was discovered in 1911
by Prof.H.K.Onnes in Netherlands in the course of studying the low temperature
properties of the metals. It was not until 1961 that the method to make superconducting
materials for successful high field magnets was discovered .Another important property
of superconductors was discovered experimentally in 1933 by W.Meissner and
R.Ochsenfeld; they found that superconductors have the tendency to exclude magnetic
field, this effect is called Meissner effect stated earlier. (Refer fig 2.3). [4]
In 1966, Powell and Danby proposed a new concept based on the use of superconducting
magnets on the vehicle. They reasoned that superconducting magnets, which can be made
very powerful in terms of their magnetic field strength, lightweight, and essentially
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lossless (except for a small power input to the cryogenic refrigerator), could levitate
vehicles that moved along a guideway of conventional room temperature conductors. In
effect, the superconducting magnets behave like extremely powerful and lightweight
permanent magnets. As the vehicle moves, its magnets induce currents in the guideway
conductors, generating a magnetic repulsive force that levitates the vehicle. The levitation
is automatic and inherent as long as the vehicle is moving, and is inherently and passively
stable. If the gap between the vehicle and the guideway decreases, the levitation force on
the vehicle increases, automatically pushing it away from the guideway.
Powell and Danby focused on maglev designs that minimize the magnitude of the
induced currents in the guideway relative to the superconducting currents in the vehicle
magnets. This in turn minimizes the losses in the guideway and the resultant magnetic
drag on the vehicle.
As the pioneers of superconducting maglev, Powell and Danby made two basic
inventions that have been key to its development:
The Null Flux Suspension
The Linear Synchronous Motor (LSM)
The Null Flux suspension makes the power losses in the guideway from the induced
currents in normal metal loops very low. As a result the magnetic drag force on the
vehicle is small. In fact, it is much smaller than the air drag force. This is important
because maglev vehicles then need much less energy per passenger mile and ton mile
than other modes of transport. Moreover, the Null Flux suspension also is inherently and
passively stable, and strongly counteracts all external forces (winds, up and down grades,
curves, etc.) that try to push the vehicle away from its equilibrium point.
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Because the levitated vehicle does not contact the guideway, conventional propulsion
cannot be used.
Instead, maglev vehicles are magnetically propelled by the highly efficient Linear
Synchronous Motor (LSM). In the LSM, a small alternating current in a second set of
guideway loops (the LSM propulsion loops are distinct from the loops that levitate and
stabilize the maglev vehicle) magnetically push on the superconducting magnets,
propelling the vehicle along the guideway. [3]
APPLICATIONS
(Click on this)
Maglev Applications (Refer fig 3.1& fig 1.3)
The principal application for maglev has always been considered to be the high
speed transport of passengers between major centers of population. Maglev is often
viewed as a sort of super-speed train that competes with airplanes for inter-city
passengers. Moreover, potential maglev systems are generally examined in the context of
routes between major population centers in a country or a region.
Maglev has many other applications, however, where it offers great advantages and
benefits, and where systems can payback their construction cost in a much shorter time
than an intercity passenger route.
The Lexus maglev cars of the future will not only float, they will spin and rise
vertically. They will also park at your window, so you can step directly into the living
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room. No more long walks home from the car park. (Refer fig 3.11).
The simple principle behind it is that when like magnetic poles face each other, they
oppose. Make the magnets really, really powerful and one magnet will make another
opposing magnet float above it, even if the magnet above is carrying a huge load. [4]
EXAMPLE
Maglev in Germany Different type of first generation Maglev system, termed Transrapid is presently
operating in Germany. Instead of using super conducting magnets on the Maglev vehicles
the German system uses conventional, room temperature electromagnets. The
electromagnets are located on each side of the vehicle, and run along its entire length.
These electromagnets are magnetically attracted upwards to iron rails positioned under
the edges of the guide way structure. The magnetic lift force then levitates the vehicle.
Transrapid has demonstrated safe and reliable operation of its maglev vehicles at speeds
up to 280 mph on its 35 km test track in Emsland, Germany, on which it has carried
hundred thousands of passengers. Transrapid has been certified as ready for commercial
service. China has indicated that it plans to build a system for the Shanghai Airport.
M-2000 (click on this)
The M-2000 vehicles are magnetically propelled by the Linear Synchronous Motor
(LSM) which maintains a 6 inch clearance between the vehicle and the guideway. The
distance between the vehicles on the M-2000 guideway is automatically maintained at a
constant value, regardless of variations in drag force on the individual vehicles. Most
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(over 90%) of the M-2000 guideway is a sequence of narrow beams that are elevated
above the ground. The narrow beams rest on a line of piers. The M-2000 vehicles
straddle the narrow beam. Superconducting magnets on each side of the vehicle
magnetically interact with the guideway panels on each side of the beam, levitating and
stabilizing the vehicle as it moves along the guideway. (Refer fig 3.6 & fig 3.7)
The M-2000 vehicles can travel on both a narrow beam and planar guideway, and
smoothly transition from one to the other. This dual guideway capability is possible
because the vehicle has quadrupole superconducting magnets. When on the narrow beam
the vertical sides of the quadrupole magnets magnetically interact with the loops on the
sides of the narrow beam. When on the planar guideway, the bottoms of the quadrupole
magnets magnetically interact with the loops on the surface of the planar guideway.
M-2000 vehicles (Refer fig 3.8 & 3.9)
The M-2000 passenger vehicle cabin dimensions are similar to a mid-size jet
airliner like the MD-80. Unlike airliners, however, all passengers on M-2000 vehicles
enjoy first class seating with ample leg room and wide, comfortable seats. The M-2000
guideway also transports freight vehicles. The trailer would roll onto and off the Maglev
vehicle in two minutes, similar to trailers carried by the Chunnel Trains.
M-2000 freight vehicles can also transport containerized freight. The M-2000 system
(Refer fig 3.2)
One of the main advantages of the M-2000 maglev system is its large clearance,
nominally 6 Inches between the vehicle and the guideway. The superconducting magnets
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on the vehicle induce currents in a guideway of normal metal loops along which the
vehicle travels.
The M-2000 suspension is very stable. Any external vertical or horizontal force on the
vehicle is automatically countered by a magnetic restoring force that pushes it back
towards its equilibrium suspension point. Using null flux guideway loops, the external
force would have to be greater than twice the weight of the vehicle to make it contact the
guideway. External forces from winds, curves, or grades, are much smaller than this
value, so that the vehicle is stable against all external forces. (Refer fig 3.3).
The M-2000 suspension has very small magnetic drag. The air drag force, however, is
significant, about 5 to 10% of vehicle weight at 300 mph. The airs drag force scales as
the square of vehicle speed, and air drag power as the cube of speed. At a speed of 150
mph, for example, air drag power is only 1/8th of that at 300 mph. (Refer table 1). [3]
ADVANTAGES & DISADVANTAGES
Disadvantages:
The cost of constructing a guideway to the requisite tolerances, its vulnerability to
foreign objects (trash, wind borne debris, etc.) and the problems of ice and snow buildup,
are some of the drawbacks
Advantages:
First, Maglev is a much better way to move people and freight than by existing modes. It is
cheaper, faster, not congested, and has a much longer service life. A Maglev guideway can
transport tens of thousands of passengers per day along with thousands of piggyback trucks and
automobiles. Maglev operating costs will be only 3 cents per passenger mile and 7 cents per ton
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mile, compared to 15 cents per passenger mile for airplanes, and 30 cents per ton mile for
intercity trucks. Maglev guideways will last for 50 years or more with minimal maintenance,
because there is no mechanical contact and wear, and because the vehicle loads are uniformly
distributed, rather than concentrated at wheels. Similarly, Maglev vehicles will have much longer
lifetimes than autos, trucks, and airplanes.
Second, Maglev is very energy efficient. Unlike autos, trucks, and airplanes, Maglev does not
burn oil, but instead consumes electricity, which can be produced by coal-fired, nuclear, hydro,
fusion, wind, or solar power plants (the most efficient source now being nuclear). At 300 miles per
hour in the open atmosphere, Maglev consumes only 0.4 mega joules per passenger mile,
compared to 4 mega joules per passenger mile of oil fuel for a 20-miles-per-gallon auto that
carries 1.8 people (the national average) at 60 miles per hour (mph). At 150 mph in the
atmosphere, Maglev consumes only 0.1 of a mega joule per passenger mile, which is just 2
percent of the energy consumption of a typical 60-mph auto. In low-pressure tunnels or tubes, like
those proposed for Switzerland’s Metro system, energy consumption per passenger mile will
shrink to the equivalent of 10,000 miles per gallon.
Third, Maglev vehicles emit no pollution. When they consume electricity, no carbon dioxide is
emitted. Even if they use electricity from coal- or natural-gas-fired power plants, the resulting CO2
emission is much less than that from autos, trucks, and airplanes, because of Maglev’s very high
energy efficiency.
Maglev has further environmental benefits. Maglev vehicles are much quieter than autos,
trucks, and airplanes, which is particularly important for urban and suburban areas. Moreover,
because Maglev uses unobtrusive narrow-beam elevated guideways, its footprint on the land is
much smaller than that of highways, airports, and railroad tracks.
Fourth, Maglev has major safety advantages over highway vehicles, trains, and airplanes. The
distance between Maglev vehicles on a guideway, and the speed of the vehicles, are
automatically controlled and maintained by the frequency of the electric power fed to the
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guideway. There is no possibility of collisions between vehicles on the guideway. Moreover, since
the guideways are elevated, there is no possibility of collisions with autos or trucks at grade
crossings. [1].
CONCLUSION
In this paper we have tried to give a brief account on maglev vehicles. We found the
following advantages of maglev vehicles:
Maglev promises to be the major new mode of transport for the 21st Century.
Because there is no mechanical contact between the vehicles and the guideway,
speeds can be extremely high.
Traveling in the atmosphere, air drag limits vehicles to speeds of about 300 mph.
Traveling in low pressure tunnels, maglev vehicles can operate at speeds of
thousands of miles per hour.
The energy efficiency of Maglev transport, either in kilowatt-hours per passenger
mile for personal transport, or kilowatt hours per ton-mile for freight, is much
lower for maglev than for autos, trucks, and airplanes.
It is pollution free, can use renewable energy sources such as solar and wind
power, and in contrast to oil and gas fueled transport, does not contribute to global
warming.
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It is weather independent, and can carry enormous traffic loads - both people and
goods - on environmentally friendly, narrow guideways.
The cost of moving people and goods by maglev will be considerably less than
by the present modes of auto, truck, rail, and air.
In addition to dramatically improving transport capabilities on Earth, maglev has
the potential to greatly reduce the cost of launching payloads into space. While it
presently costs $10,000 per pound to orbit payloads using rockets, the energy cost
to orbit that same pound would be only 50 cents per pound, if it were
magnetically accelerated to orbital velocity.
As ultra high velocity magnetic launchers are developed, the cost of reaching
space will come down to everyday, mass market standards.
These and additional maglev applications such as maglev for mining, the Water
Train and others will hold an important place in transportation history
Though there are some disadvantages like its high cost it can be reduced as research is
going on to further to develop the maglev vehicles which would be cheaper and would
provide enhanced benefits as compared to today’s maglev vehicles. In the future with
improvement in its technology there is no doubt that maglev vehicles will overtake any
other form of transportation and if it is extensively used promises a better future of man.
With all the views mentioned above, we conclude that the maglev system really turns out
to be a milestone for the forthcoming generation. The list of advantages seems to
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be never ending. The needs of present day transportation system such as high speeds, low
power consumption, pollution free, time saver, are all met by maglev vehicles. Thus it
seems to be an outstanding gift for the future generation.
FIGURES
Fig 1.1 Fig 1.2
Fig 1.3 Fig 1.4
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Fig 1.5 SCHEMATIC OF MAGLEV VEHICLE IN U-SHAPED GUIDEWAY
Fig 2.1 Fig 2.2
Superconductivity Fig 2.3 Fig 3.1
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Fig 3.2 Fig 3.3
Fig 3.4 Fig 3.5
Fig 3.6 Fig 3.7
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Fig 3.8
Fig 3.9
Table 1 Fig 3.10
" Tsurumi forested land line " (Osaka)" sky train “(Canada)
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" HSST " JR " Miyazaki experimental line "
" Trance rapid " (Germany)" M - Bahn " (Germany)
Maglev
REFERENCES
[1] James Powell and Gordon Danby,” MAGLEV, The New Mode of transport for the 21st Century”, Summer issue of 21st century Science and technology,2004
[2] “Maglev contest Media Advisory,”http://www.pubaf.bnl.gov/pr/bnlpr041897.html, April 18, 1997[3] http://www. The Maglev 2000 of Florida Corporation.htm[4] “Special issue on applications of superconductivity”, IEEE , vol-92,10-OCT-2004,pps1511[4] http://www. Minority Report Get the tech today - Product Reviews - CNETAsia.htm
Other references:1]R.J.Thorne, D.B.Montegomery “Applications of superconducting cables-in-conduit conductors to coil systems for maglev vehicles”,IEEE Transactions on applied superconductivity, Vol.3,No 1,March 1993,pps 438.2]Thomas Penick, "Magnetically levitated vehicles”,11 Nov 19983]Don Ketchen, “Superconducting magnets and their applications”,IEEE,Vol.92,Oct 2004, pps 1683.
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4]Laurence Hecht, “Magnetrain:A 600-mph Railroad Suspended by Magnets”,The Road to the 21st Century, winter 2000-2001 issue.
References for videos:1] http://www.magnemotion.com2] ] http://www. The Maglev 2000 of Florida Corporation.htm
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