Rotor Drop Test Stand For AMB Rotating Machinery, Part I: Description Of Test Stand And Initial Results

Rotor Drop Test Stand For AMB Rotating Machinery, Part I: Description Of Test Stand And Initial Results

Kirk, R.G., Swanson, E.E., Kavarana, F.H., Wang, X., 1994
Proc. of Fourth International Symposium on Magnetic Bearings, Zurich, pp. 207-212.

Abstract

The recent increase in the number of critical path rotating machinery applications using active magnetic bearing (AMB) technology has focused awareness and necessity for proper design of the auxiliary or backup bearings. These emergency bearings are essential for protection of the AMB stator in the event of control system failure or limited operation during momentary overload conditions wherein the AMB control system is still active. The current research project is concerned with the former design requirement, which is referred to as rotor drop. The rotor system and the auxiliary bearing support structure are equally important and influence the nature of the resulting rotor drop transient response. Limited testing of production machinery has demonstrated both successful drop tests and limited cases of auxiliary bearing failure. The reliability required for critical path machinery makes it essential to completely understand what parameters control the nature of the rotor drop transients. The design and construction of a full scale research test stand at Virginia Tech will be documented in this paper. The overall goals are summarized and initial test results of rotor drops on the rigidly supported auxiliary bearings are presented.