Magnetic levitation uses the magnetic force of suspension to make the object in a state of frictionless, contactless suspension. The magnetic levitation looks simple. Because the principle of magnetic levitation technology is integrated with electromagnetics, electronic technology, control engineering, signal processing, mechanics and dynamics. Typical mechatronics high-tech.
principle:
The system of magnetic levitation technology consists of a rotor, a sensor, a controller and an actuator 4, wherein the actuator comprises an electromagnet and a power amplifier. Assume that at the reference position, the rotor is subjected to a downward disturbance and will deviate from its reference position. At this time, the sensor detects the displacement of the rotor from the reference point, and the microprocessor as the controller converts the detected displacement into a control signal, and then The power amplifier converts this control signal into a control current that generates a magnetic force in the execution magnet that drives the rotor back to its original equilibrium position. Therefore, regardless of whether the rotor is disturbed downward or upward, the rotor can always be in a stable equilibrium state.
The main purpose is to use the eddy current generated by the high-frequency electromagnetic field on the metal surface to achieve the suspension of the metal ball. When a metal sample is placed on a coil with a high-frequency current, a high-frequency electromagnetic field generates a high-frequency eddy current on the surface of the metal material. This high-frequency eddy current interacts with the external magnetic field to cause the metal sample to receive a Lodz force. The role. In a suitable space configuration, the direction of the Lorentz force can be opposite to the direction of gravity. By changing the power of the high-frequency source to make the electromagnetic force equal to the gravity, the electromagnetic suspension can be realized. Generally, the alternating current frequency through the coil is 104-105 Hz.
At the same time, the Joule heat generated by the eddy current on the metal can melt the metal, thereby achieving the purpose of smelting the metal without the container. By 2012, in the field of space materials research, EML technology played an important role in the study of crystal growth, solidification, nucleation and deep subcooling in microgravity and containerless environments.
There are three types of magnetic levitation in the world by 2012. One is the constant conducting magnetic levitation represented by Germany, and the other is the superconducting dynamic magnetic levitation represented by Japan. Both magnetic levitations require electricity to generate magnetic levitation power. The third type is China's permanent magnet suspension, which uses special permanent magnet materials and does not require any other power support.
