Magnetic Levitation Trains
Japanese magnetic levitation Train MLX01 on workplace
Magnetically levitated (MAGLEV) trains area unit thought of as a future application of HTS development. To know why, we have a tendency to should look in briefly at the history of the railroads. The event of trains and rails began within the early 1800s. The fashionable typical train is not any quicker (~110 mph) than those of the late Nineties. Therefore typical trains have reached the tip section of their development.
France, Germany, and Japan have developed “high-speed” or “bullet” trains capable of speeds of 150-180 mph. This improvement in speed relies upon improved rails and controls. However, this technology has additionally reached the tip section of its development. One limiting issue for these trains is that the dearly-won and long maintenance of the rails. Therefore it’s the mechanical friction between train wheels and metal tracks that limit this technology. This leads U.S. In the event of the magnetically levitated (no friction) trains. We have a tendency to in brief describe the history of this development.
The idea of magnetic levitation transportation has been around since the first decennium. The good thing about eliminating the wheel/rail friction to get higher speeds and lower maintenance prices has nice attractiveness. The essential plan of a magnetic levitation train is to levitate it with magnetic fields therefore there’s no physical contact between the train and also the rails (guideway).
To get from this straightforward thought to a true operating system involves monumental technological developments. Whereas there has been no development of magnetic levitation trains within the U.S., in the Federal Republic of Germany and Japan they need developed functioning demonstration trains (in Japan they need one system that has transported over 1,000,000 people). Up to now there aren’t any existing construction styles that embrace HTS magnets, however we are going to provide a temporary history of the magnetic levitation trains in Japan and Federal Republic of Germany to assist make a case for why HTS magnets ought to be thought of in future development.
Two essentially totally different ideas of magnetic suspension have evolved.
- The electro magnetic suspension (EMS) uses electromagnets of the train body that area unit drawn to the iron rails. The vehicle magnet wrap round the iron guideways and also the engaging upward force lifts the train.
- The electrodynamic suspension (EDS) levitates the train by repulsive forces from the evoked currents within the conductive guideways.
In each of those systems the levitating magnets are a unit mounted to a variety of “bogies” connected to the train body by a secondary suspension of dampers and comes. But there’s an elementary distinction between these 2 systems. Within the EMS system, the “air gap” between the gateways and train magnets is incredibly tiny (~1/2 inch), whereas the “air gap” within the EDS system could also be as giant as 8-10 inches.The little airgap of the EMS system implies way more rigorous controls to keep up this small gap.
The superconducting magnets that are utilized in these magnetic levitation systems are of the coldness selective. As a result of these should operate below the liquid argonon temperature (4.2 K) these area unit dearly-won and complicated systems. The technological advantage of operational HTS magnets at cryogen temperatures (77 K) area unit monumental.