Maglev: A New Generation in Railroad Technology

The Japanese have one of the most advanced mass railroad systems in the world. The Shinkansen, referred to as the Bullet Train, covers thousands of kilometers of tracks at speeds in excess of 200 kilometers per hour. Each day the more than 270 bullet-nosed trains convey 340,000 passengers throughout Japan. Since the Japanese system went into service in 1964, the trains have carried more than 1.8 billion travelers without an injury or a fatality. The well-maintained system is not only safe and fast, but it is not petroleum dependent.

The Japanese National Railways made a huge investment in time, money, and technical personnel in building the Shinkansen. Now, as always, on the cutting edge, they are working on developing the next generation of high-speed supertrains.

Technical specialists working at the Japanese National Railways have been experimenting with a prototype magnetic levitation train. The maglev (an acronym for magnetic levitation) will actually race along a guideway at almost 500 kilometers per hour, floating on a magnetic field. The maglev will operate on the basic principles of electromagnetism.

The train depends on magnetism for propulsion, suspension, and braking. Specialized sets of magnetic coils are built into the body framework of the train. Other sets of magnetic coils are installed in the bottom and sides of a U-shaped guideway that cradles the train. When electric power is switched on, the coils on the train and in the guideway produce a magnetic field with north and south poles. The magnetic forces between the coils on the train and the coils in the guideway can be made to attract or repel each other by changing their polarity. The train is propelled by magnetic attraction between the magnets aboard the train and those on the guideway. As the successive and rapid bursts of magnetism move from coil to coil with lightning speed, the train accelerates after them, resulting in the forward movement of the train. In summary, then, the magnetic coils on the train are attracted by the opposing polarity of the guideway coils immediately ahead of them.

Magnetism is also used to lift the train off the guideway to reduce friction, diminishing wear and tear where the train meets the guideway. The special coils aboard the train and on the guideway repel each other, making the train float. This repulsion force is so strong that it can lift a moving 10,000-kilogram train 10 centimeters off the guideway. The braking action is accomplished by changing the polarity of the train coils relative to those of the guideway coils, reversing their relationship from one of attraction between two unlike poles to one of repulsion between two like poles.

Japanese National Railway System engineers believe the new maglev trains will be an improvement over the Shinkansen. Not only will the maglev be faster than the Bullet, it will be more comfortable and more reliable as well. Since the maglev rides on a magnetic wave, it has a low noise level and a diminished vibration level. This is an important consideration for the people living in neighboring areas, particularly in a country with such high population density. Low maintenance is another advantage of the maglev train because of the fact that the maglev has no moving motor parts or steel wheels as conventional trains do. This factor virtually eliminates guideway wear and tear and prevents costly breakdowns. In addition, much less time will be spent on equipment inspection, track repair, and parts replacement.

The Japanese are still conducting test runs of the new prototype maglev train and have been running unmanned maglev prototypes since 1972. In 1997, a remote-controlled maglev in Miyazaki, Japan, set a world speed record of 341 miles per hour.