Design of a high speed test rig for bearing and rotordynamic

Student thesis: Master's thesis, 30 credits, for qualification at advanced level, 300.0 Credits

  • Michael Källberg
Master of Science in Engineering Technology
This thesis describes the information and drawings that the chosen design
is based on. The main assignment is to design a test rig for rotor dynamic
and bearings measurements. From start it was a desire to use magnetic
bearings to support the main shaft in the rig. The magnetic bearing
technology is relative young and very expensive compared to conventionally
load carriers. The bearings levitate the shaft with a strong magnetic field
and consequently there is no mechanical contact between the shaft and the
bearing. This technique requires a fast and well tuned closed loop control
system though the system is unstable. In the chosen machine design, one of
the magnetic bearings is also used as a magnetic force exciter instead of a
load supporting bearing.

In the end of this work it became a fact that detailed knowledge about the
dynamic behaviour and limitations of the magnetic bearings are essential to
be able to design the shaft with the desired performance. That knowledge
was not available and therefore is further analysis necessary before
building this rig.
Publication date2004
Publishing institutionTillämpad fysik, maskin- och materialteknik


  • test rig, design, magnetic bearings