Stabilizing Gyroscopic Modes in Magnetic-Bearing-Supported Flywheels by Using Cross-Axis Proportional Gains (Paperback) (ISBN-13: 9781289252038)

For magnetic-bearing-supported high-speed rotating machines with significant gyroscopic effects, it is necessary to stabilize forward and backward tilt whirling modes. Instability or low damping of these modes can prevent the attainment of desired shaft speed. We show analytically that both modes can be stabilized by using cross-axis proportional gains and high- and low-pass filters in the magnetic bearing controller. Furthermore, at high shaft speeds, where system phase lags degrade the stability of the forward-whirl mode, a phasor advance of the control signal can partially counteract the phase lag. In some range of high shaft speed, the derivative gain for the tilt modes (essential for stability for slowly rotating shafts) can be removed entirely. We show analytically how the tilt eigenvalues depend on shaft speed and on various controller feedback parameters.

Author: Nasa Technical Reports Server (Ntrs),Gerald V. Brown
ISBN-10: 1289252033
ISBN-13: 9781289252038
Publisher: Bibliogov
Language: English
Published: 07/29/2013
Pages: 26
Format: Paperback
Weight: 0.15lbs
Size: 9.69h x 7.44w x 0.05d