Abstract
A force measurement dynamometer has been constructed which will be the primary instrument used to measure the dynamic forces applied by a magnetic bearing to a rotating shaft. The dynamometer consists of two force measurement assemblies, named flexnounts, mounted directly to the shaft support bearing housings which utilize strain gage measurements to determine the magnitude of radial loads transmitted through the shaft. The design of the flexmounts focused on two main objectives: 1) minimizing coupling in the strain gage measurements to simplify calibration procedures and reduce cross-coupled stiffnesses, and 2) providing ample sensitivity for accurate force measurement while maintaining sufficient radial stifffiess to keep the first critical speed of the rotor-bearing system above the maximum operating shaft speed of the system. Analytical verification of the design was provided via a finite element model to determine the level of coupling between the primary axes of measurement and a lumped-inertia model of the rotor-bearing system to confirm critical speed locations. Finally, a static force calibration of the flexmounts was performed with the primary goal of measuring the forces applied by the magnetic bearing to within I︢% accuracy over the widest range of forces possible.
Henderson, Gregory Lane (1994). The design, construction, and calibration of a dynamometer used to measure forces applied by a magnetic bearing to a rotating shaft. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1994 -THESIS -H496.