MAGNETIC LEVITATION TRAINS (MAGLEV) BY: JONEY THAKUR

INDEX INTRODUCTION MAGNETIC LEVITATION LEVITATION TYPES ELECTROMAGNETIC SUSPENSION ELECTRODYNAMIC SUSPENSION PROS AND CONS OF DIFFERENT TECHNOLOGIES ADVANTAGES & LIMITATIONS OTHER APPLICATIONS CONCLUSION

Driving without wheels flying without wings

NEED & NECESSITY Trends in increased mobility of large masses with changing lifestyle for more comfort are leading to congestion on roads with automobiles increasing pollution levels from automobiles, depleting fuel resources ,critical dependence on the fuel import problems of wastage of time in air traffic delays and growing safety concerns embankments, and cuttings necessary for roads and railroads are avoided

MAGNETIC LEVITATION In this process an object is suspended above another with no other support but magnetic fields Manipulating magnetic fields and controlling their forces can levitate an object The electromagnetic force is used to counteract the forces of gravitation If the levitated magnet is rotated, the gyroscopic forces can prevent it from Is the use of magnetic fields to levitate a (usually) metallic object overturning.

SUPERCONDUCTING MAGNET

PROPULSION SYSTEM Electrodynamic Propulsion is the basis of the movement in a Maglev system The principle that electromagnetic propulsion follows is that “opposite poles attract each other and like poles repel each other”. The three major components of a propulsion system: A large electric power source Metal coils that line the entire guideway Guidance magnets used for alignment

LEVITATION TYPES: The principal two systems : 1. Electromagnetic Suspension- attractive 2. Electrodynamic Suspension- repulsive

ELECTROMAGNETIC SUSPENSION Suspension uses conventional electromagnets located on structures attached to the underside of the train Current runs through the guiderail and the electromagnets of the train are turned on. EMS uses the attractive force of a magnet beneath the rail to lift the train up. Guidance coils are placed on side of the train to keep it centered,during turns as well.

ELECTRODYNAMIC SUSPENSION EDS uses a repulsive force between two magnetic fields to push the train Superconducting magnets (SCM) located on the bottom of the train to levitate it off of the track By using super cooled superconducting magnets, the electrical resistance in superconductors allows current to flow better and creates a greater magnetic field

PRINCIPLE OF EDS:

PROS & CONS OF VARIOUS TECHNOLOGIES: TECHNOLOGY PROS CONS EMS(Electromagnetic suspension) Magnetic fields inside and outside the vehicle are less than EDS; proven, commercially available technology that can attain very high speeds (500 km/h); no wheels or secondary propulsion system needed The separation between the vehicle and the guideway must be constantly monitored and corrected by computer systems to avoid collision due to the unstable nature of electromagnetic attraction; due to the system's inherent instability and the required constant corrections by outside systems, vibration issues may occur EDS (Electrodynamic suspension) Onboard magnets and large margin between rail and train enable highest recorded train speeds (581 km/h) and heavy load capacity; has recently demonstrated (December 2005) successful operations using high temperature superconductors in its onboard magnets, cooled with inexpensive liquid nitrogen Strong magnetic fields onboard the train would make the train inaccessible to passengers with pacemakers or magnetic data storage media such as hard drives and credit cards, necessitating the use of magnetic shielding; limitations on guideway inductivity limit the maximum speed of the vehicle; vehicle must be wheeled for travel at low speeds.

A NEW TRACK IN THE RUNNING: INDUCTRACK Similar to the EDS system. Difference is use of permanent magnets rather than superconducting magnets. This system uses an “arrangement of powerful permanent magnets, known as a Halbach array, to create the levitating force”. The Inductrack is similar to that of the EDS system in that it uses repulsive forces. Guideway is made from “two rows of tightly packed levitation coils”.

The train itself has two Halbach arrays; one above the coils for levitation and the other for guidance A major benefit of this track is that even if a power failure occurs, the train can continue to levitate because of the use of permanent magnets.

ADVANTAGES: Magnetic Fields: low intensity Energy consumption: 30% less energy than a high speed train Noise Levels : No noise caused by wheel rolling or engine Maglev noise is lost among general ambient noise At 100m - Typical city center road traffic is 80 dB Vibrations: Just below human threshold of perception Safety: 20 times safer than an airplane Collision is impossible because only sections of the track are activated as needed.

Power Supply: 110kV lines fed separately via two substations Power Failure: Batteries on board automatically are activated to bring car to next station Batteries charged continuously Fire Resistance of vehicles: Latest non-PVC material used that is non-combustible and poor transmitter of heat Maglev vehicle carries no fuel to increase fire hazard Operation Costs: Virtually no wear. Main cause of mechanical wear is friction. Magnetic Levitation requires no contact, and hence no friction. Specific energy consumption is less than all other comparable means of transportation.

LIMITATIONS Maglev guide paths are bound to be more costly than conventional steel railways Lack with existing infrastructure They are limited to where maglev lines run Very difficult to make construction of maglev lines commercially viable The fact that Maglev train will not be able to continue beyond its track may seriously hinder its usefulness

OTHER APPLICATIONS: NASA plans to use magnetic levitation for launching of space vehicles into low earth orbit. Boeing is pursuing research in MagLev to provide a Hypersonic Ground Test Facility for the Air Force The mining industry will also benefit from MagLev

CONCLUSION Railways using MagLev technology are on the horizon. Low maintenance of the MagLev is an advantage Energy efficient and Environmental friendly Energy created by magnetic fields can be easily replenished No large effect on the topography of a region Sustainability of Maglev is very Positive Considering everything Maglev has to offer, the transportation of our future and our children’s future is on very capable tracks.