Dynamics of Rotating Systems

Limits, Modeling and Design of High-Speed Permanent Magnet Machines

“…[81,82]. Finally, stability of rotation has been analyzed comprehensively in the field of rotordynamics [83][84][85][86], however some important conclusions on rotordynamical stability have not been included in literature on electrical machines.…”

“…5.3. However, this model gives a qualitative insight into rotors' dynamical behavior and will be used here to infer about the stability limit in general [86,129].…”

“…If the condition (5.14) is fulfilled these vibrations are hardly noticeable -the motions damp out very quickly. However, if the rotational speed is higher than the limit defined by (5.14) the amplitude of the vibrations will grow and will be limited only by the system non-linearities [86]. The rotor-bearings system from Fig.…”

“…Nevertheless, these phenomena will not be analyzed in detail in this chapter and the reader will be referred to literature. Self-excited vibrations, on the other hand, require no external force for inception 1 [86,126]. They arise within range(s) of rotational speed, usually after a certain (threshold) speed which is correlated with intrinsic properties of the system.…”

“…The list of literature that is relevant for the subject of this chapter is quite long; this study was mainly influenced by the works of G. Genta [86,127,128], D. Childs [126,129] and A. Muszynska [130,131].…”