Abstract:

Considering the slim configuration of a space solar power station like Solar Tower, the space flexible beam moving in the plane of a circular orbit is taken as the research object, and a coupling dynamic model of the attitude motion and bending vibration is established based on the Hamilton principle in the mass-centered floating coordinate system. The simple assumption of the attitude motion is introduced and its rationality of the hypothesis is verified. Based on this assumption, the influence of the attitude motion and gravity gradient on the first-order frequency of the bending vibration is analyzed. Its effect is in the form of the harmonic fluctuation: the bending vibration frequency decreases with the attitude motion and both of them are enhanced when the initial attitude angle increases. At the same time, the modal equations in the form of the Mathieu equation are deduced. By using the small parameter perturbation analysis method, the stable curves of the bending vibration under different initial attitude angles are obtained. It is shown that the larger the initial attitude angle is, the larger the unstable area is.

Key words: Space solar power station, Flexible beam, Mathieu equation, Attitude vibration coupling, Stability analysis