1. Brief Introduction of Magnetic Levitation Device
Magnetic levitation is a technology that uses magnetic fields to levitate objects in the air. A technology that uses magnetism to overcome gravity to levitate objects. It is also known as magnetic levitation technology. Magnetic levitation is a method of lifting objects without friction. It's also more efficient because less energy is used to overcome friction. All it needs is a strong magnetic field. A permanent magnet is just what is needed to provide this magnetic field. NdFeB powerful magnets are the most widely used permanent magnets in the magnetic levitation field.
2. The working principle of magnetic levitation
There are three basic principles of maglev:
1）When the magnetic field close to the metal changes, the electrons on the metal will move and generate current.
2）The magnetic effect of current. When current flows in a wire or a piece of metal, a magnetic field is created. The electric coil becomes a magnet.
3）The magnets will interact with each other, the same polarity repels each other, and the opposite polarity attracts each other.
3. Magnetic levitation application
Maglev train
The Maglev train is a modern high-tech rail vehicle. It realizes the non-contact suspension and guidance between the train and the track through electromagnetic force, and then uses the electromagnetic force generated by the linear motor to drive the train. Its main technical system principle includes three parts: ① suspension system ② propulsion system ③ guidance system. Among them, the suspension system achieves the effect of train suspension through the principle of magnets with the same name "magnetically repel each other, and magnets with different names attract each other". The propulsion system uses permanent magnet synchronous traction motors to keep the train moving in a straight line. So what materials are these magnets made of? Among them, the most important is the rare earth permanent magnet material.
The rare earth permanent magnet material is an alloy composed of rare earth metal elements (samarium, neodymium mixed rare earth metals) and transition group metals (such as cobalt, iron, etc). which are pressed and sintered by powder metallurgy and magnetized by a magnetic field. Magnetic materials are mainly divided into rare earth cobalt-based permanent magnet materials and rare earth iron-based permanent magnet materials. They all have the following characteristics:
(1) High magnetic properties, such as high magnetic energy product;
(2) Linear demagnetization characteristics: their demagnetization curves are basically straight lines, the recovery line coincides with the demagnetization curve, and the reversible magnetic permeability is close to 1.0;
(3) High temperature resistance: the Curie temperature of sintered cobalt-based rare earth permanent magnets can reach 850 degrees Celsius, so it can work in high temperature environments;
(4) Good temperature stability.
Because of its excellent permanent magnet properties, it is widely used in maglev trains. The permanent magnet synchronous traction motor, that is, the propulsion system of the maglev train, often uses samarium cobalt permanent magnets or neodymium iron boron permanent magnets.
Magnetic Levitation Household Decoration
Magnetic Levitation Globe.
At present, there are two types of upper suspension system and lower suspension system on the market.
A permanent magnet is fixed on the support bottom of the lower suspension system, and a circular plastic frame is arranged above the support, and a metal coil electromagnet is arranged in the frame. There is also a magnet on the inner wall of the globe, and the electromagnet on the top and the permanent magnet on the base repel each other, and this repulsive force is used to suspend the globe. In order to make the levitation stable, a detector is installed in the coil above the bracket, which specifically detects the change of the magnetic field at the bottom, and generates a compensation current to adjust the electromagnetic intensity to make the globe float smoothly. When hovering stably, as long as you rotate it slightly, the globe will continue to rotate continuously.
There is a permanent magnet on the top of the bracket of the upper suspension system, and a discharge magnet on the lower part, which produces an attractive force, which makes the globe suspend.
Maglev ornaments series.
Now there are many on the market, such as magnetic levitation photo frame, magnetic levitation wine display stand, magnetic levitation electronic cigarette display stand, magnetic levitation tablet computer display stand, magnetic levitation mobile phone display, magnetic levitation mannequin, and so on.
Magnetic suspension bearings.
Magnetic suspension bearings use magnetic force to levitate the rotor, and there is no mechanical contact between the rotor and the stator. The weight of the rotor is supported by magnetic force, and the entire rotor is suspended in the air.
Magnetic levitation motor
DC magnetic levitation motor is also called magnetic levitation motor, magnetic force motor, bearing less motor, it is a motor with a new structure. Its principle is: a permanent magnet is embedded on the rotor, and a coil is wound on the stator to form a multi-pole electromagnet, which generates a rotating magnetic field. Using the principle of mutual repulsion of the same magnetism, the rotor can be repelled by the stator and rotate. Not only that, the rotor can also be suspended and rotated.
Maglev doors and windows
Although the magnetic levitation sliding door is similar to the principle of the magnetic levitation train, it is not really suspended on the track (too expensive to realize), but still moves on the track through pulleys.