THREE PRACTICAL EXAMPLES OF MAGNETIC BEARING CONTROL DESIGN USING A MODERN TOOL

摘要

The use of magnetic bearing in industrial applications has increased due to their unique properties. Nowadays efficiency and predictability in handling rotors on magnetic bearings is asked with the same standard as conventional rotors on oil or roller bearings. First of all one must be aware of the special technical properties of magnetic bearing designs. The dynamic behaviour of the rotor combined with requirements of the application define the desired bearing characteristic. With modern tools /1/, covering the mechanical aspects as well as the electronic controllers and their digital implementation on a DSP, these properties can be designed. However, despite the use of such efficient tools engineering practice is needed. Therefore this paper summarises the major steps in the control design process of industrial applications. Three rotors supported on magnetic bearing with their specific dynamic behaviour are presented: A very small high speed spindle (120000 rpm), a small, industrial turbo molecular pump rotor (36000 rpm) and a large multi-stage centrifugal compressor (600 to 6300 rpm). The results of the analyses and their experimental verification are given.