Abstract: The stability sensitivity analysis is presented for rotor-sliding bearing systems. By applying the stability theory on the system, a kind of generalized energy-Liapunov function was introduced to reflect the stability status of bearing and rotor subsystems and their aggregated system. Based on that the stability index is defined and deduced which is used to describe the influences of the bearings and the rotor to the stability of their compound system. Some examples are given to show the correctness of the difinition and the success of the approach as well as its uniqueness compared with some other sensitivity analysis methods.

Key words: Liapunov function, Rotor-bearing system, Sensitivity, Stability