Back in 1922, Herman, Germany? Herman Kemper put forward the principle of electromagnetic levitation, and applied for the patent of maglev train in 1934, and began to weave a dream of high-speed riding for human beings. People's pursuit of speed has turned to magnetic levitation with greatly reduced friction and resistance. From a technical point of view, magnetic levitation is not as advanced as inventions such as quantum computers. With a small magnet and a nail, we can easily feel the attraction and repulsion caused by magnetic force. Of course, this suspension is only schematic and it is difficult to reach a stable state. Scientists' ideas are not something we can fiddle with with with a simple magnet.
After decades of development, magnetic levitation technology has formed two major research directions, namely EMS system and EDS system represented by Germany and Japan respectively. EMS (Constant Magnetic Gravitation) system approved by Germany is the basic principle of using conventional electromagnets to attract general iron-containing substances to adsorb and suspend trains. EDS (Exclusion Suspension) system, which is favored by Japan, uses the principle of superconducting magnetic levitation to generate repulsive force between wheels and rails, so that the train runs in suspension. At present, both models have reached the speed of about 500 kilometers per hour, and both schemes are feasible, which is really difficult to distinguish.
Shanghai maglev train is the first demonstration operation line of maglev train in the world. After completion, it only takes 6-7 minutes from Longyang Road Station in Pudong to Pudong International Airport. Shanghai maglev train is a kind of "constant magnetic attraction type" (referred to as "constant conductivity type"), which is designed according to the principle of "opposites attract" and is a suction suspension system. The suspension electromagnets installed on the bogies on both sides of the train and the magnets laid on the track are used to suspend the vehicle through the suction generated by the magnetic field.
Electromagnets are installed at the bottom of the train and at the top of bogies on both sides. The induction plate and the induction steel plate are respectively installed above the I-beam track and below the upper arm. Control the current of electromagnet to keep a gap of 65,438 0 cm between electromagnet and track, and balance the attraction between bogie and train with the gravity of train. By the attraction of magnets, the train can float about 65,438+0 cm, and the train can be suspended on the rails. This must accurately control the current of the electromagnet.
The driving principle of suspension train is exactly the same as that of synchronous linear motor. Generally speaking, the alternating current flowing in the coils on both sides of the track can turn the coils into electromagnets, and the train will start because of its interaction with the electromagnets on the train.
The N pole of the electromagnet at the head of the train is attracted by the S pole of the electromagnet installed on the front track and repelled by the N pole of the electromagnet installed on the back track. When the train moves forward, the current in the coil flows in the opposite direction, that is, the original S pole becomes the N pole, and the N pole becomes the S pole. When the cycles alternate, the train will run forward.
Stability is controlled by the navigation system. The "constant magnetic attraction" guiding system is a group of electromagnets installed on the side of the train for guiding. When the train deviates from the left and right, the guide electromagnet on the train interacts with the side of the guide rail to produce repulsive force, which makes the vehicle return to the normal position. When the train runs on a curve or ramp, the control system can control the operation by controlling the current in the guide magnet.
The idea of "normal guidance" maglev train was put forward by German engineer Herman Corpster in 1922.
"Normal-oriented" maglev train, the working principle of track and motor is exactly the same. Just arrange the "rotor" of the motor on the train and lay the "stator" of the motor on the track. Through the interaction between "rotor" and "stator", electric energy is converted into positive kinetic energy. We know that when the "stator" of the motor is electrified, the "rotor" can be driven to rotate through electromagnetic induction. When the power is transmitted to the "stator" of the track, the train is driven to move linearly like the "rotor" of the motor through electromagnetic induction.
Shanghai maglev train runs at a speed of 430 kilometers per hour, and only one train can run in one power supply area. There are isolation nets at 25 meters on both sides of the track and protective equipment on both sides. The radius of the bend is 8000 meters, and the naked eye is almost a straight line; The minimum radius is1300m. Passengers will not feel uncomfortable. The most advanced isolation devices in the world are installed within 50 meters on both sides of the whole track.
Shanghai maglev train line starts from Longyang Road Station of Shanghai Metro Line 2 in the west and ends at Shanghai Pudong International Airport in the east, with a total length of 29.863 kilometers. The world's first maglev commercial traffic line, jointly developed by China and Germany, dug its first shovel in Pudong on March 1 2002, put into trial operation on February 3 1 2003, and officially started commercial operation on June 1 2003. This is the world's first commercial maglev line.
This is the coolest train in the world today. The carriage with locomotive is 27.196m long and 3.7m wide. The middle carriage is 24.768 meters long, and it can travel back and forth between Shanghai and Pudong Airport in 14 minutes. In it, you will personally experience the strange feeling brought by this "land passenger plane".
It is an ideal super express train in 2 1 century, and all countries in the world attach great importance to the development of maglev train. At present, China, Japan, Germany, Britain and the United States are actively studying this kind of car. Japan's superconducting maglev train has been overloaded with people and is about to enter the practical stage, running at a speed of more than 500 kilometers per hour.
High-speed rail generally refers to trains with a speed of more than 200 kilometers per hour. In the early 1950s, France and China first put forward the idea of high-speed train, and started the test work at the earliest. 1976, a high-speed train drawn by diesel locomotives was put into use in Britain, which was the fastest passenger train in Britain at that time, with a top speed of 200 kilometers per hour.
French and China take electric locomotives as the research object, and their high-speed electric traction trains set a record of 260 kilometers per hour at 1978. 198 1 10 in June, the new high-speed train "T.G.V" was officially put into use on the Paris-Lyon trunk line. Compared with traditional trains, the air resistance of streamlined trains is reduced by one third. Equipped with high-power power device, strong climbing ability. It can climb 35% steep slopes or start on slopes at high speed. It still uses ordinary railway lines and once set a speed record of 380 kilometers per hour.
Who owns the high-speed rail now? a target = _ blank href =/view/ 12805 1 . htm & gt。 On the basis of], train and highway, the power system, walking system, vehicle shape and track system have been improved, without changing the basic characteristics of traditional trains and railways. In addition to the improvement of traction locomotives, although some new attempts have been made in the track, such as the short-distance monorail in West Germany, Japan, the United States and other countries, its construction cost and complexity are huge compared with ordinary railways, which can not meet the needs of long-distance and heavy-haul railway transportation, so it has not been widely used. Because of the problems existing in the traditional traction locomotive and track system, such as wheel-rail friction, it is difficult to further improve the speed. If we want to make a big leap in railway transportation, we need to adopt a brand-new design in the traction locomotive and track system. For example, some countries are currently developing machines. /a & gt； Cars.