Rotordynamics and Machine Optimization
To get maximum performance and stability from a magnetic bearing system, rotordynamics - the dynamic motion of the rotating shaft - is critical. Synchrony® rotordynamics specialists work closely with OEMs to develop numerical models to ensure that your machine is stable and performs properly throughout its operating range.
The rotordynamic analysis and machine optimization begins with developing a precise mathmatical model of the machine. This Synchrony model accurately represents how the system will perform with our magnetic bearings.
The system is analyzed to determine:
- All system modes are stable (Eigen value analysis)
- Bending modes are both observable and controllable (Mode shape analysis)
- Unbalance forces are within bearing design limits (Unbalance analysis)
- Displacements are within acceptable limits (Unbalance analysis)
- The effect of gyroscopic forces over the entire speed range are acceptable (Campbell plot analysis)
Magnetic bearings are tested in the machine as the last step in the optimization process. The numerical modeling of the shaft and the performance of the bearing are validated by measuring the closed-loop transfer function. During a closed-loop measurement, the shaft is excited at a specific frequency by the magnetic bearing. The response is measured by the position sensors. Shaft response is measured over a range of frequencies (e.g., 0-2000 Hz).
Because the final optimization involves closed-loop measurements without the need for external instrumentation (through the user interface), Synchrony can typically complete the final optimization in less than six hours for a new machine.