2. ďINTRODUCTION
ďBASIC PRINCIPLE OF MAGLEV TRAINS
ďTECHNOLOGY AND TYPES
ďMERITS AND DEMERITS
ďSTABILITY
ďEVACUATED TUBES
ďPOWER AND ENERGY
ďCOMPARISON WITH AIRCRAFT AND CONVENTIONAL
TRAINS
ďECONOMICS
ďEXISTING MAGLEV SYSTEMS
ďSUMMARY
ďREFERENCE
3. What is meant by MAGLEV?
MAGLEV = MAGNETIC + LEVITATION
Any thing which may levitate(raise or float) by means of a
magnetic power is simply called as magnetic levitation.
4. LEVITATION :
Meaning :
⢠A Latin word meaning lightness.
⢠Process by which an object is suspended by a physical force against gravity, in a
stable position without any solid physical contact.
Principle :
⢠First a force is required vertically upwards and equal to the gravitational force.
⢠Second for any small displacement of the levitating object a returning force
should appear to stabilize it.
Major Types :
⢠Electromagnetic levitation
⢠Buoyant levitation
⢠Aerodynamic levitation
5. Magnetic Levitation :
Definition:
⢠Magnetic suspension is a method by which an object is suspended with no
support other than magnetic field.
Principle:
⢠Magnetic pressure is used to counteract the effects of the gravitational and
any other activities.
Magnetic Field:
⢠A magnetic field is a field of force produced by a magnetic object or particle,
or by a changing electrical field.
⢠It is detected by the force it exerts on other magnetic materials and moving
electric charges.
Magnetic pressure:
⢠Any magnetic field has an associated pressure that is contained by the
boundary conditions on the field.
6. ďMaglev is the system of transportation that uses
magnetic levitation to suspend ,guide and propel the
vehicles using magnets.
ďFirst described by Robert Goddard, American Rocket
Scientist, 1909 Scientific American.
ďLater in 1937 & 1941 a series of German patents for
maglev trains propelled by linear motors awarded to
Hermann Kemper .
ďIn the 1960s in Britain Eric Laithwaite developed a
functional maglev train.
7. Maglev trains have to perform the following functions to operate
in high speeds
1.Levitation 2.Propulsion 3.Lateral Guidance
Basic principle of Maglev Trains
8. Levitation
â˘The passing of the superconducting magnets through levitation
coils on the side of the track induces a current in the coils and
creates a magnetic field. This pushes the train upward so that it
can levitate 10 cm above the track.
â˘The train does not levitate until it reaches 50 mph, so it is
equipped with retractable wheels.
9. Propulsion
â˘An alternating current is ran through electromagnet
coils on the guide walls of the guide way. This creates a
magnetic field that attracts and repels the
superconducting magnets on the train and propels the
train forward.
â˘Braking is accomplished by sending an alternating
current in the reverse direction so that it is slowed by
attractive and repulsive forces.
10. Lateral Guidance
â˘When one side of the train nears the side of the
guideway, the super conducting magnet on the train
induces a repulsive force from the levitation coils on the
side closer to the train and an attractive force from the
coils on the farther side. This keeps the train in the
center.
11. ďUses monorail track with linear motor
ďUses magnets to reach a really high velocity
ďFloats about 1-10cm above the guideway on a magnetic
field.
ďPropelled by the guideway
ďOnce the train is pulled into the next section the
magnetism switches so that the train is pulled on again.
12. ďThere are 2 notable types of maglev technology:-
â˘Electromagnetic suspension(EMS)
â˘Electrodynamic suspension(EDS)
13. ďElectromagnets attached to the train
ďHas ferromagnetic stators on the track
and levitate the train.
ďHas guidance magnets on the sides
ďA computer changes the amount of
current to keep the train 1 cm from the
track.
ďMax speed -438km/hr
ďHas on-board battery power supply.
14. ďSuper cooled superconducting magnets
under the train. Levitate about 10 cm.
ďThe field in the train due to superconducting
magnets(JR-Maglev) or an array of permanent
magnets(Inductrack).
ďThe force in the track is created by induced
magnetic field in wires or conducting strips in
the track.
ďNaturally stable. Requires no feedback control.
ďRequires retractable wheels at low speed , max speed â 522km/hr
15.
16. TECHNOL
OGY
MERITS DEMERITS
EMS â˘Magnetic fields inside & outside the
vehicle are less than EDS.
â˘No wheels or secondary propulsion
required
â˘Can attain very high
speed.(500km/hr).
â˘Constant monitoring correction
of separation between vehicle &
guideway using computer
systems essential.
â˘Due to inherent instability and
corrections ,vibration issues may
occur.
EDS â˘Onboard magnets and large
separation enable highest recorded
speeds(581km/hr) and heavy load
capacity.
â˘Naturally stable and hence no
feedback control required.
â˘Strong magnetic field makes the
train inaccessible to passengers
with pacemakers or storage
media like hard drives and credit
cards.
â˘Vehicle must be wheeled for
low speed travel.
17. TECHNOLOGY MERITS DEMERITS
INDUCTRACK
SYSTEM
(PERMANENT
MAGNET EDS)
â˘Failsafe suspension-No power
required to activate magnets.
â˘Can generate enough force at
low speeds to levitate the train.
â˘The train can slow down on its
own in case of power failures.
â˘The array of permanent
magnets are cost effective than
electromagnets.
â˘Requires wheels
when the vehicle is
stopped
â˘New technology ,
still under
development , no
commercial version
or full scale system
prototype
18. ďEMS system rely on active electronic stabilisation..
ďAll EDS systems are moving systems.
ďSince these vehicles fly,stabilisation of pitch , roll and
sway is required
ďIn addition to rotation , surge , sway and or heave
can be problematic.
19. ďSome systems use the use of vac trains-maglev
train technology used in evacuated tubes , which
removes the air drag.
ďThis increases the speed and efficiency greatly .
ďIt is a proposed design for super high-speed
transportation about 4000-5000 mph.
ďBut the passengers may suffer from the risk of
cabin depressurization in the event of a train
malfunction.
ďHence require tunnel monitoring system for
repressurization
20. ďEnergy is used to make the Maglev train levitate and to
stabilise the movement.
ďMain part of the energy used to overcome the air drag.
ďFor very short distances the energy for accelerating is
considerable.
ďBut the power used to overcome the air drag increases with
square of velocity and hence dominates at high speed.
21. FEATURE MAGLEV TRAIN CONVENTIONAL
TRAIN
Speed Allow higher top
speeds since they
donât rely on
wheels for
propulsion.
Speed is limited by
the use of wheels
for propulsion.
22. Maintenance Require insignificant
guideway maintenance.
Their electronic vehicle
maintenance is minimal
Hence more reliable
Rail is subjected to wear &
tear due to friction
,increases exponentially
with speed.
This increases running cost.
All weather
operation
Unaffected by snow ,
severe cold , rain or
high winds.
Can accelerate &
decelate regardless of
slickness of guideway
May encounter problems
due to degradation of
guideway caused by
weather conditions.
Efficiency No rolling resistance
due to lack of contact
between track &
vehicle.
This improves power
efficiency.
Efficiency is affected by
rolling resistance due to the
contact with the track.
23. ďMany maglev have lift-to-drag ratio that exceed that of
aircraft.
ďBut jet transport aircraft take advantage of low air density
at high altitudes to reduce drag during cruise.
ďAirlines cannot come close to the reliability or
performance of maglev trains in all weather conditions.
ďHas significant safety margin as they are designed not to
crash into other.
24. ďThe initial investment is similar to other high speed
rail roads. (Maglift is $20-$40 million per mile and I-279
in Pittsburg cost $37 million per mile 17 years ago.)
ďOperating expenses are half of that of other railroads.
ďA train is composed of sections that each contain 100
seats, and a train can have between 2 and 10 sections.
ďThe linear generators produce electricity for the cabin
of the train.
25. TESTING TRACKS
ď120 m test track of General Atomics at San Diego , USA.
ďTranrapid , a German maglev company has test track at Emsland ,
Germany of length 31.5km.
ďJR-Maglev , Japan has a test track that can reach a speed of
581km/hr.
26. IMPORTANT OPERATIONAL SYSTEMS
ďLinimo , Japan â commercially automated urban maglev
system commenced on March 2005.
ďShangai maglev train , China â EMS high speed system
started operation on April 2004.
ďHML 03 â The first EMS maglev opened to public at
Daejeon South Korea in 1993.
27. UNDER CONSTRUCTION
ďAMT Test Track â Powder Springs, Georgia
ďApplied levitation test track â California.
ďBeiging S1 line.
PROPOSED PLANS
ďPenang-Kuala Lampur-Singapore line -Malaysia
ďMelbourne Maglev Proposal
ďMumbai â Delhi
ďKochi metro
28. ďThey consume less energy.
ďRequire no engine.
ďMove faster than normal trains because they are not affected by
ground friction; their rights-of-way, meanwhile, cost about the
same to build.
ď Incompatible with existing rail lines, unlike traditional high-
speed rail.
ďInitial cost is very high.
29. ďWikipedia ââMaglev Trainsâ
ď Science reporter magazine October 2014.
ďHeller, Arnie (June 1998). "A New Approach for Magnetically Levitating
Trainsâand Rockets". Science & Technology Review.
ďHood, Christopher P. (2006). Shinkansen â From Bullet Train to Symbol of
Modern Japan. Routledge.
ďScience journal.âMaglev trainâ April 19, 2010,
http://science.howstuffworks.com/maglev-train.htm