Title:Modal damping identification of a gyroscopic rotor in active magnetic bearingsAuthor(s):Gudrun Mikota, Andreas Josef Pröll, Siegfried SilberAbstract:Modal testing is done for a rotor in active magnetic bearings whose first backward gyroscopic mode is prone to instability. In the absence of process forces, the rotor is excited from one of its active magnetic bearings, and modal parameters are identified at rotational speeds up to 60000 rpm. Experiments are done with excitation directions x and y and for different versions of the active magnetic bearing position controller. The excitation current consists of a series of triangular impulses; the frequency spectrum of the windowed excitation signal contains a narrow band that covers the first backward and forward gyroscopic modes of the rotor. Within this frequency band, natural frequencies, damping ratios, and mode shapes are identified. The results demonstrate the suitability of the chosen excitation and enable a comparison of active magnetic bearing position controllers that should stabilize the first backward gyroscopic mode.Booktitle:Proceedings of 11. Internationale Tagung Schwingungen in rotierenden Maschinen (SIRM 2015), Magdeburg, Deutschland, February 23-25, 2015Page Reference:page Paper-ID 42, 10 page(s)Publishing:2/2015