Scientists finalize test platform for ultra-speed maglev train_美文

Scientists finalize test platform for ultra-speed maglev train

The first is magnetic levitation, which uses superconductors to produce powerful magnets to elevate the train above the track, thus remove the friction with the track and enhance the speed.

"The reason that an aircraft moves faster than any vehicle on the ground is similar - the friction from the air is much smaller than the ground," Zhao explained.

The concept of maglev transportation was first presented in the mid-20th century and the first commercial maglev train line was put into operation at Birmingham Airport in Britain in 1984, which had a speed of only 42 km per hour because of the technology at that time.

Currently, China and Japan are actively developing such technology, and the maglev train connecting the Bund and Pudong Airport in Shanghai is the world's fastest commercial line with speeds up to 431 km per hour.

The second technology used to speed up the train is to put it into a vacuum tube to reduce air resistance, which is the only source of friction for a magnetic levitation train.

"Compared with conventional superconductors, the high-temperature superconductors require less stringent environmental demands, and thus reduce the cost of the train," Zhao said.

For example, the conventional superconductors used on Japan's levitation trains need to stay at about -270 C to keep their superconducting state, which needs liquid helium cooling.

In contrast, high-temperature superconductors of the maglev train running in Pudong Airport can keep the superconducting state at -180 C to -200 C, which can be refrigerated with liquid nitrogen, a cooling agent one hundred times cheaper than liquid helium.