磁懸浮列車：火車技術(shù)的一個新時代

Japan has 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 more than 270 bullet-nosed trains convey 340，000 passengers throughout Japan.

日本是擁有世界上最先進的火車體系的國家之一。新干線，即子彈頭列車，以每小時200千米的速度跑完數(shù)千千米的距離。每天有270列子彈頭列車運送34萬乘客往來日本全境。

Since the Japanese railroad 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.

自從1964年日本鐵路體系運行以來，火車已運送18億旅客，無一傷亡。這種性能良好的系統(tǒng)不但方便快捷，而且不用石油供給能量。

Technical specialists working at Japanese National Railways had experimented with a prototype magnetic levitation train. The maglev （an acronym for magnetic levitation） actually races along a guideway at almost 500 kilometers per hour， floating on a magnetic field. The maglev operates on the basic principles of electromagnetism.

致力于日本國家鐵路的技術(shù)專家已經(jīng)對標準的磁懸浮列車進行了試驗。這種列車實際上可以沿指定的軌道以每小時近500千米的速度浮于磁面前行。磁懸浮列車的運行是基于電磁學(xué)的基本原理。

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.

這種列車通過磁力進行推進、懸浮、制動。一些特制的磁線圈安裝于火車的主體結(jié)構(gòu)中，其他的磁線圈被安裝于支撐列車的U形鐵軌的底部和側(cè)面。通電后，列車及鐵軌上的磁線圈將產(chǎn)生南北極磁場。通過改變極性，列車及鐵軌上的磁線圈生成的磁力會相互吸引或相互排斥。

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 break-downs. In addition， much less time will be spent on equipment inspection， track repair and parts replacement.

低維修率也是磁懸浮列車的一個優(yōu)勢，因為它們不像傳統(tǒng)列車有活動的電機配件或鋼輪。事實上，這減少了鋼軌的摩擦與損耗，防止了需要高昂維修費用的故障。此外，設(shè)備檢查、鐵軌維修、零件更換也無須太多時間。