What is MagLev?• MagLev stands for Magnetic Levitation.• Magnetic forces lift, propel and guide a vehicle over a guideway.• Utilizing special electrical power and control systems.• Uses electromagnets to push/pull train along guideway.
Magnets• Opposite attract, like poles repel.• North repels north, south attracts north.• Super fast electro-magnets switching poles thousands of time per minute.• Propel the train as well as levitate it off the track.
Maglev Consist of Three parts1)Levitation2)Guidance3)Propulsion
Types of Maglev TrainsBased on the technique used for Levitation the are two types of Maglev trains1. Electromagnetic Suspension -Attractive2. Electrodynamic Suspension -repulsive
1) In electrodynamic suspension (EDS), both the rail and the train exert a magnetic field, and the train is levitated by the repulsive force between these magnetic fields.2) The basic Principle is based on electromagnetic Induction3) The superconducting magnets move at a very high speed and magnetic field changes in the “8” shaped coils4) The trick is that the magnets fixed in trains moves slightly below the center of “8” shaped coils so the flux changing at the lower half is more then the upper part
5) The magnetic pole of the lower half is same as thatof the moving magnet so both repel Each other.6) Upper part has a opposite polarity so it attract themoving magnet.7) Both forces combine and produce the component offorce that pulls the train in the upward Direction
What is Electromagnets?• Current runs through a wire creates an electric field.• Guideway constantly changes magnetic fields.• North vs. South Polarity
EDS System1)The coils in the beam propel the train in theforward direction.2) Once the train is reached to a proper speedthen due to the magnetic field changing in the“8” shaped coils north and south pole producewhich produce upward Component of force andlift the train3) The electric current supplied to the coils inthe guideway walls is constantly alternating tochange the polarity of the magnetized coils.
4)This change in polarity causes the magneticfield in front of the train to pull the vehicleforward, while the magnetic field behind thetrain adds more forward thrust.
1) In electromagnetic Suspension train levitateabove the steel rails due to the attraction betweenthe opposite poles of magnets one in the guidewayand the other in the undercarriage.2)Distance Between the rail and the undercarriagemust maintained 15mm.3) Train also remain suspended in air when it is notmoving .4)Guidance Magnets Ensure that the train may notCollide with the rails During Motion.
5) Minor Changing Between the Magnets and theRail Produces a Varying force and this force is veryunstable do Complex electronic Feedback system isNecessary to maintain the accurate Distance.6)The system varies the Current in electromagnetsand Control the Magnetic force of attraction.
EMS system1)In EMS system electromagnetsAttract the track and the train levitate2) Linear Motors are at the Center ofThe track which propel the train.3) Gray area is Concrete and Blue areais Steel.
1)The Maglevs speed can vary from standstill tofull operating speed by simply adjusting thefrequency of the alternating current in the stator.2) To bring the train to a full stop, the direction ofthe travelling field is reversed.3) Even during braking, there isnt any mechanicalcontact between the stator and the rotor.4)View of the Stator from bottom==
1) Onboard magnets and large margin between rail and train enable highest recorded train speeds (581 km/h)2) Heavy load capacity1) Strong magnetic fields onboard the train would make thetrain inaccessible to passengers with pacemakers ormagnetic data storage media such as hard drives and creditcard.2) vehicle must be wheeled for travel at low speeds.3) Magnetic Shielding is necessary .
1) Magnetic fields inside and outside the vehicle are less than EDS. 2) commercially available technology that can attain very high speeds (500 km/h). 3) No wheels needed.1) The separation between the vehicle and the guideway mustbe constantly monitored and corrected by computer systems toavoid collision due to the unstable nature of electromagneticattraction.2) Vibration issues may occur.