Abstract
The object of this paper is to study a method for passing through the critical speeds of rotating shaft systems, and in particular, to search for optimal turning points and returning points for minimizing the maximum flexural amplitude by changing the driving acceleration after the initial start-up. This method is based on the following idea. A large acceleration is available during transition through critical speeds because the maximum amplitudes of flexural deflection are reduced ; however it is unsuitable except the region of critical speed because the torsional deflection increases. In order to realize the optimal operating curve, a linear optimal tracking system is applied. This control system consists of optimal state feedback and a compensation input. It has been proved that this control system reduces transient torsional vibration due to sudden torque change and torsional resonance vibration when the shaft passes through its resonance region.
