The active control of flexible rotors is a challenging control problem because of the plant variation with rotational speed, the open-loop instability of the plant at super-flexible rotational speeds, and the presence of synchronous disturbances. This paper examines one of these problems, the open-loop nonsynchronous instability that is caused by internal damping in the rotating structure. This instability occurs only when the rotor is operated at high rotational speeds, rotational speeds greater than the first flexible-mode frequency of the free standing rotor. The emphasis in the paper is the development of constraints placed on controllers designed to stabilize the open-loop unstable, high-speed operation of flexible rotors. These constraints are developed by analyzing a specific two-mass flexible rotor system. This multi-input, multi-output system can be described by 'complex coefficient' single-input, single-output models by the use of complex coefficient differential equations. Using control analysis and design methods recently developed for these complex coefficient transfer functions, the constraints placed on stabilizing controllers are developed. Stabilizing controllers are shown to have minimum and maximum gain and bandwidth constraints.
Stability constraints on the control of flexible rotors
Stabilitaetsanforderungen an das Regelsystem von Satelliten-Schwungrad-Energiespeichern mit Magnetlagern
1987
6 Seiten, 12 Bilder, 9 Quellen
Conference paper
English
Stability Constraints on the Control of Flexible Rotors
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