Can you believe it?
China has built the world's fastest train, with a speed of up to 620 kilometers per hour, which is simply flying, shocking the world!
How did such a magical train come about? And what does high-temperature superconductivity mean? Why are American netizens sour?
<h1 class="pgc-h-arrow-right" data-track="13" > the world's fastest suspension train, made in China! </h1>
What is a maglev train? As the name suggests, it means not to touch the orbit, so suspended in the air. This year, Chengdu, China, officially demonstrated the world's first high-temperature superconducting high-speed maglev engineering prototype.
How amazing is its levitation? This behemoth weighs 12 tons, but it is like a light boat on the surface of the water when it stops on the track, and it can be slowly pushed forward with a light stroke of the hand.
After testing, it can reach a maximum speed of 620 kilometers per hour in the atmospheric environment, which is one step closer to the concept of "hyperloop".
The so-called "hyperloop" refers to the super train with maglev technology as the core in a low vacuum state, and theoretically this speed can reach more than 1,000 kilometers.
This means that the land passage time from Beijing to Guangdong is only about two hours!
Of course, there is still a long way to go to get there.
However, the high-temperature superconducting suspension prototype vehicle should not be underestimated, it uses a series of new technologies and new processes such as all-carbon fiber lightweight body and large-load high-temperature superconducting maglev technology.
Therefore, stability, energy saving, lightweight, no noise, no chemical pollution, safety and comfort have become its many advantages, and the stability is more than any current means of transportation.
It is reported that the next scientific research direction of the R & D team is to combine the train and the future vacuum pipeline technology to complete the feasibility of operational safety, economy and environmental protection.
In this way, the ground-to-ground flight of the hovering train is truly realized, and the speed gap between the land high-speed rail and the air flight is filled.
< h1 class= "pgc-h-arrow-right" > the history of the development of hovering trains</h1>
Is it true that such a fast, flying train can't be in trouble? How did humans achieve such exaggerated speeds?
In fact, about the concept of maglev train, everyone can still imagine it, and the mind is probably the picture of the train levitated by the magnetic force of the magnet.
Then, what the high-temperature superconductivity mentioned earlier refers to, I am afraid that many people are not very clear.
Let's start with the concept of superconductivity. Generally, the electrical appliances we use will have resistance, and the materials used in high-speed rail now are naturally available. Superconductivity refers to material conductors whose resistance can decrease with the decrease of temperature until the resistance will become zero after breaking through a certain critical value.
Then when the resistance is zero, the superconducting material has super good conductivity, but also has a complete anti-magnetic, this anti-magnetic is that you put the superconducting material in the magnetic field, the magnetic flux line will go around it, and there is no magnetic induction strength inside it.
Because of the zero resistance of superconductors, it can make full use of electrical energy, deliver current without loss, and do not consume energy on material heating.
The "high temperature" in high-temperature superconductivity does not refer to the hundreds or thousands of high temperatures used in the smelting of steel in our traditional cognition, on the contrary, it often refers to the temperature of minus celsius.
This is because the ultra-low temperature value required in the superconductor studied by humans is often not easy to achieve, and it can only be formed with a temperature much higher than the critical value, but the temperature sometimes reaches about minus 200 degrees Celsius, which is "high temperature" superconductivity.
And because the superconductor resistance is zero, the current does not decay after flowing to the train circuit, but is stored in the train coil.
The train has no additional consumption of electrical energy, and then use the motor to convert the electrical energy into kinetic energy, it can quickly "float" and slide, reaching a speed that is difficult for ordinary trains to achieve.
However, theory is theory, and it is certainly a combination of technologies in many fields that are truly realized. Therefore, the realization of the maglev train is not achieved overnight, and its forward history is also full of ups and downs.
In 1922, German engineers first began to study maglev technology, and in 1934 applied for a patent for a maglev train.
Since the 1960s, countries have begun to invest in related research and development work, and since then, Germany, Japan and other countries have been at the leading level in the world in this regard.
China only began basic research on magnetic levitation technology in the early 1980s.
But the first commercial maglev train appeared in the United Kingdom in 1984, its maglev line was only 600 meters long, operating at a speed of 42 kilometers per hour, and was closed 11 years later due to maintenance and operation problems.
In 1989, Germany laid the first maglev train, and in 2000 and 2003, it was put into operation in the maglev project.
However, due to the developed transportation network in Germany, and there are disputes in the capital and safety technology of maglev trains, even if Germany is the place of technological invention, it has always faced the situation that maglev trains cannot blossom.
On the contrary, the maglev trains on the Japanese side have a tendency to catch up.
In 1962, Japan's maglev began to study, until 2005 officially operated Japan's first maglev railway, with a total length of about 9 kilometers, a maximum speed of 100 km / h, to achieve full unmanned driving.
In 2013, Japan's new maglev train reached a speed of 500 kilometers per hour, which has been called "the fastest train in history".
Speaking of China, the first maglev railway was operated in Shanghai in 2003, with a total length of about 30 kilometers, and the maximum operating speed was 430 kilometers per hour, but at that time, whether it was maglev vehicles or technology, it was imported from Germany.
Since then, about 10 cities, including Beijing and Guangdong, are promoting related research and development and construction work.
Among them, vehicle lightweight has become the development trend of maglev trains. This is not only to match the speed of the train up to 600 km/h, but also to meet the principle that the lighter the carriage, the less buoyancy is required.
Therefore, aluminum alloy has become the best cost-effective material, not only high specific strength, excellent extrusion performance, good weldability, but also can be used to create interiors such as decoration, air conditioning, seats and ventilation systems.
By 2016, it had achieved China's first self-produced medium and low-speed maglev train, which had the characteristics of safety, low noise and strong climbing ability, and many of the achievements had reached the international leading level.
The high-temperature superconducting high-speed maglev prototype vehicle unveiled this year is suspended on the permanent magnet track as a whole, with a linear motor in the middle of the track, and there is no wheel at the bottom of the car, but it is replaced by a superconducting levitation device.
The height of suspension is between 10 and 30 mm and can be set as needed. The body is stable, and people ride it no differently than they ride a high-speed train, except that they feel faster and maybe even more comfortable.
So, how is the high-temperature superconducting high-speed maglev prototype vehicle realized? What is the difference between it and the previous magnetic levitation technology?
<h1 class= "pgc-h-arrow-right" > long road, maglev train has a long way to go</h1>
China has built the world's fastest train, shocking the world. Can a train really reach such an exaggerated speed? How?
Magnetic levitation technology is generally divided into two types, one is the constant conductive high-speed magnetic levitation, and the other is the high-speed superconducting magnetic levitation. These two technologies should be represented by Germany and Japan.
The German research team focused on the study of the constant conductivity high-speed magnetic levitation, while Japan is more fond of high-speed superconducting magnetic levitation technology. China, on the other hand, has studied both technologies, some of which are the best of both worlds.
The often conductive maglev train uses the principle of "same-sex repulsion, heterosexual attraction", so that the N-pole electromagnet on the front track of the locomotive attracts the S-pole electromagnetic on the front track, and the N-pole electromagnet on the back track repulses with the front of the car, thus generating forward power.
As the train moves forward, as the current flows through the coil, the S and N poles are constantly swapped, so that the train can be pushed forward all the time.
This kind of maglev train also has a guiding system, once the train is driving on a curved road and ramp, the left and right displacement occurs, and the system will generate repulsive force on the side of the guide rail, so that the vehicle can ensure that it does not deviate from the track.
Roughly speaking, the principle between the train and the track is the same as that of the electric motor, which is the conversion between electrical energy and mechanical energy.
The overall technology is relatively simple, and the electromagnetic attraction is relatively small. The German side can achieve a suspension air gap between 8 and 10 mm, and the current suspension speed of such technologies can reach between 400 and 500 kilometers per hour.
Although the superconducting maglev train also relies on magnetic interaction, it is mainly necessary to use the complete anti-magnetic properties of the superconductor to place superconducting coils on the body and track to generate a strong repulsive force.
The induced current is generated when the train is started, which creates an electromagnetic attraction of the superconducting magnet, which is converted into forward power and vertical levitation.
The air gap of the superconducting maglev vehicle suspended on the track developed by japan is relatively large, generally about 100 mm, and this kind of technology is much more complicated, and the final train speed can reach more than 500 km per hour;
China's maglev this time uses high-temperature superconductivity. The coil components of high-temperature superconductivity constitute a superconducting magnet, which has a large current and high transmission efficiency during operation.
Specifically, some key components of the train must achieve near-zero resistivity at a certain temperature to achieve full anti-magnetic resistance in order to carry out dissipative-free transportation.
In the past, the superconducting maglev train was "low-temperature superconducting magnetic levitation technology", which used liquid helium at minus 269 degrees Celsius to ensure that the superconducting material was working at ultra-low temperatures.
But the "high temperature superconductivity" we use is to use liquid nitrogen with a relatively high temperature to ensure the performance of superconducting materials, under the cooling effect of liquid nitrogen, superconducting materials are about zero resistance in an environment of nearly minus 200 degrees Celsius, so electrical energy transmission is also about equal to zero loss.
It is important to know that liquid helium is more than 50 times more expensive than liquid nitrogen, so our manufacturing costs have also been greatly reduced.
As soon as the high-temperature superconducting maglev train came out, it attracted worldwide attention and landed on the hot search of major domestic platforms.
After the relevant videos spread abroad, they caused a heated discussion among the majority of foreign netizens, including some media praise, but there were also many voices of doubt, some of which were even more sour.
They began to spread rumors that China must have stolen American technology to build this train. In this regard, many netizens who understand the matter said bluntly, "Wake up, China has more registered patents than the United States."
Some netizens also quipped, "Chinese actually used a time machine, traveled to the United States in 2015, and took the technology from them."
Of course, the foregoing is just some jokes. China's high-temperature superconducting levitation is undoubtedly independently developed and manufactured, which marks that China is one of several countries in the world with mature medium and low-speed maglev train technology.
However, although a breakthrough has been achieved in technology, the maglev high-speed rail project is still more or less controversial.
At present, it is only vehicle testing, and the construction of tracks, power supply, and signaling devices has not yet begun.
On the one hand, once the maglev line encounters a power outage, there will be great trouble, especially how to achieve reliable power supply for long-distance maglev? On the other hand, how to overcome the rescue and recovery problem when the train fails?
These are all issues that need to be considered. However, only with the realization of medium and low speed maglev trains, it has green and economic characteristics.
According to the current cost of 500 million to 800 million yuan per kilometer of China's subway and about 200 million to 300 million yuan of light rail, the cost of medium and low speed maglev systems is about 150 million to 250 million yuan per hectare.
The life of maglev trains is generally 35 years, and the life of tracks is 80 years; while the life of ordinary trains is 20 to 25 years, and the life of tracks is only 60 years.
The annual operation and maintenance cost of the wheel rail train is as high as 4.4% of the investment, while the operation and maintenance cost of the maglev train is only about a quarter of the former, so in the long run, the development of the maglev train must be a trend.
Human beings have always been in the pursuit of breakthroughs in speed.
Ground transportation comparable to the speed of aircraft may soon be realized, which will bring passengers a convenient and comfortable ultra-high-speed travel experience, while also driving the economic convergence between urban circles.