MAGNETIC LEVITATION TRAINSubmitted by

BLESSON M BABU

Mechanical Engineering Department

Lakshmi Narain College of Technology-Excellence, Bhopal (M.P.) 462021

MAGNETIC LEVITATION TRAIN

By BLESSON M BABUME - ‘F’ SEM- 5TH

Problem• Current land transportation is slow• Land is limited by friction• Flying is expensive • Air and land travel takes up a lot of fuel

Solution

• Reduce friction for land travel• “Hover” just over the railroad tracks• Process is simpler than making a plane fly• Staying on land is safer

The Maglev Train HistoryIn the 1960s in Britain Eric Laithwaite developed a functional maglev train. His maglev had 1.6 km of track and was in detail tested. His research was stopped in 1973 because lack of money and his progress was not enough. In the 1970s, Germany and Japan also began research and after some failures both nations developed mature technologies in the 1990’s……………………………………..

The Maglev Train

• The Maglev Train is one of the fastest transport media in the whole world.

• The maximum speed reached for a Maglev train has been 581 km\h in Japan.

• The Maglev Train uses magnets to reach a really high velocity.

• It doesn’t touch the floor. It levitates because the magnets.

• Maglev is a short for Magnetic Levitation.

How does it work

• A maglev train floats about 10mm above the guidway on a magnetic field.

• It is propelled by the guidway itself rather than an onboard engine by changing magnetic fields

• Once the train is pulled into the next section the magnetism switches so that the train is pulled on again.

• The Electro-magnets run the length of the guideway.

Superconducting Magnets

• Superconducting magnets on train induce current on conducting sheet

• Induced currents generate magnetic repulsive force

• In conducting sheet guideway there are power losses in sheet

• Slightly corrected by making small conducting loops

• Still significant losses…

A Better Design

• James Powell, and Gordon Danby invented the “Null-Flux” system

• When the vehicle is at the symmetry point of the loop, the net magnetic flux through the loop circuit is zero

FREQUENCY REFERENCE SIGNAL FOR SPEED CONTROL

CONTROLLER

TRACK THREE-PHASE POWER INPUT

TRAIN WITH SPEED

SENSOR

It works like this

Propulsion• 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.

• Braking is accomplished by sending an alternating current in the reverse direction so that it is slowed by attractive and repulsive forces.

How Transrapid Works Support System• The electromagnets on

the underside of the train pull it up to the ferromagnetic stators on the track and levitate the train.

• The magnets on the side keep the train from moving from side to side.

• A computer changes the amount of current to keep the train 1 cm from the track.

This means there is no friction between the train and the track!

Halbach Array’s are a special arrangement that cancels the magnetic field above the magnets, but still allows a field below the magnets. The permanent magnets that will be using are made out of Neodymium Iron Boron (NdFeB)

Levitation System’s Power Supply

• Batteries on the train power the system, and therefore it still functions without propulsion.

• The batteries can levitate the train for 30 minutes without any additional energy.

• Linear generators in the magnets on board the train use the motion of the train to recharge the batteries.

• Levitation system uses less power than the trains air conditioning.

Propulsion System

• The system consists of aluminum three-phase cable windings in the stator packs that are on the guideway

• When a current is supplied to the windings, it creates a traveling alternating current that propels the train forward by pushing and pulling.

• When the alternating current is reversed, the train brakes.

• Different speeds are achieved by varying the intensity of the current.

• Only the section of track where the train is traveling is electrified.

.

Forward Propulsion

• No connection with track• Linear Synchronous Motor used• AC current in windings in the guideway• Speed in controlled by frequency of the AC power• High efficiency because only the section of track that the train is

on needs current

The magnets on the train produce eddy currents in the levitation coils when traveling over them

The method of levitation requires a certain velocity before levitation will occur

Same principle as a rotary synchronous motor

The rotor will be the Halbach Array The stator will be coils of wire on the sides of the guide way

The input will be a three-phase varying frequency signal at a very low frequency (2-10 Hz)

Levitation • The passing of the superconducting magnets by figure eight

levitation coils on the side of the tract 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.

• The train does not levitate until it reaches 50 mph, so it is equipped with retractable wheels.

The MagLifter

Advantages of a maglev Train

• The German Transrapid is about 20 times safer han airplanes • 250 times safer than conventional railroads

• 700 times safer than automobile travel

• Speeds up to 500 km/h.• A accident between two maglev trains is nearly

impossible because the linear induction motors prevent trains running in opposite directions.

Magnetic Field:• The magnetic field created is low, therefore

there are no adverse effects.

The Maglev Train and Society

• The Scientifics want the Maglev train to be fast and economical.

• They want it to be something that anyone can use.

• The big problem about this is that the pieces for the maglev are really expensive

• The procedure to build it up is very expensive as well

The Maglev Train and Environment

• The Maglev train doesn’t contaminate a lot.• It doesn’t need any kind of fuel.• It doesn’t send out any CO2.

The Maglev Train and Politics

• The government has a big relationship with the Maglev Train.

• It gives the money to the Scientifics so they research about it.

• The Maglev train researchers use the government figure for some kind of advertisement.

The Maglev Train and Culture• The Maglev Train has helped the people in

some countries to think better about the travel by train.

• I think it wouldn’t have worked in USA because it is a bigger country that is developing and that is focusing now in other industries. They also have plains that connect every main city. It is easy to travel in America.

Conclusion

• There’s definitely a better way to travel• Since there is no friction these trains can

reach high speeds.• It is a safe and efficient way to travel.• Maglev transportation has a questionable

future

Bibliography

• Wikipedia• http://www.railserve.com/maglev.html• http://www.tech-faq.com/how-does-a-• maglev-train-work.shtml• http://www.o-keating.com/hsr/

maglev.htm• Book: The mistery of Magnets

THANK YOU…