What is Electromagnetic Bearing?
Electromagnetic bearing, a plain bearing that uses electric field force and magnetic field force to make the shaft suspended.
The principle of electromagnetic bearings is similar to that of a maglev train. Maglev train is a modern high-tech rail transit tool, which realizes contactless suspension and guidance between the train and the track through electromagnetic force, and then uses the electromagnetic force generated by the linear motor to pull the train to run, reducing friction.
The electromagnetic bearing detects the position deviation signal of the shaft through the position sensor, sends the signal to the controller, and controls the current of the electromagnet through the power amplifier, so as to generate a change in electromagnetic force to make the spindle suspended in the specified position.
2. Advantages and disadvantages of electromagnetic bearings
Advantages of electromagnetic bearings:
1) High speed
Electromagnetic bearings allow the rotor to rotate at high speed, its speed is mainly limited by the strength of the material, can work under supercritical, hundreds of thousands of revolutions per minute, and the rotation accuracy of the rotor has reached the micron level or even higher, which is the speed and accuracy that ordinary mechanical bearings can far from reach.
2) Low power consumption
Since the electromagnetic bearings have no mechanical contact, there is almost no friction, and the power consumption to overcome friction is very low. At a speed of 10,000 r/min, the power consumption is only about 15% of that of mechanical bearings.
3) Low maintenance cost and long life
Because electromagnetic bearings have no contact and no wear, no contact between moving surfaces, no mechanical friction and contact fatigue, it solves the problem of loss and life of mechanical components, and the reliability of electronic components is largely higher than that of traditional mechanical parts.
4) No lubrication required
Electromagnetic bearings do not need lubrication, eliminating lubrication system and other devices, that is, saving space and not polluting the environment by the lubrication system.
5) It can work in vacuum and a wide temperature range, and the structure can be diversified.
Disadvantages and difficulties of electromagnetic bearings:
1) Electrostatic bearings require a lot of electric field strength, and the application is limited.
2) The controller is the key, how to design a controller with simple structure, good performance and easy debugging is a technical difficulty.
3) How to evaluate the impact of processing and manufacturing errors on electromagnetic control is also a difficult point.
4) How to control the instability of the rotor requires further research and application experience.
3. Application of electromagnetic bearings
At present, electromagnetic bearings have been widely used in many fields, such as ultra-high-speed trains, ultra-high-speed centrifuges, hydro turbine generators, angular momentum flywheels of space vehicles, flow meters, density meters, power meters, vacuum pumps, precision regulators and gyroscopes.
Post time: Apr-15-2026
