RESEARCHERS at Siemens have developed a magnetic bearing which does not require any additional sensors.
The technology was developed in collaboration with the Technical University of Vienna.
Magnetic bearings can be used in compressors or vacuum pumps and are said to be very efficient. They are free of friction, supporting very high energy efficiency, without wearing.
The technology is based on the forces of attraction and repulsion between magnetic parts. However, the force of the magnets must be constantly controlled in real time to keep the shaft suspended. Position sensors are currently used to record the position of the shaft.
The researchers created a demonstrator unit comprising of a ball that is held suspended by magnetic fields without any additional sensors. This could open the mass market to magnetic bearings.
The demonstration technology utilises the fact that the position of the shaft alters the magnetic field and thus influences the inductivity of the electromagnets. The researchers developed an analysis method to determine the position of the shaft quickly.
Measurements are taken directly at the power supply for the electromagnets, with no additional wires required.
Siemens says magnetic bearings have a long service life, require little maintenance, and support high speeds of more than 200,000RPM. They do not require lubricants, eliminating concerns about leaking oil and environment contamination.
Add a comment