Electromagnetic bearings and self-bearing motors

Description

Magnetic bearings may be the very epitome of a mechatronic system: electro-magnactial forces act on a mechanical system, a system that is inherently unstable and thus also requires an appropriate controller.

In contrast to conventional bearings magnetical bearing work without mechanical contacts and thus never wear out. For this reason, such bearings are mostly used in applications in which the (ferromagnetic) body on which a force is to act moves quickly relative to the magnetic actuator. In these applications, freedom from wear is particularly important. Lubrication can be dispensed with. Other applications of magnetic bearings use the freedom of movement that is present due to the air gap, for example to move a shaft of a tool spindle to be mounted with high precision along a specified path. 

The chair is particularly interested in the non-linear control methods of signal processing, which are required for high-precision, fast web control. This includes observers both for the operation of the control (such as status and disturbance variable observers, imbalance compensation) and for process monitoring (process force reconstruction from the bearing currents). For this purpose, different types of bearings are examined in different applications.