Design Of Piezoelectric Damping System For Passive Vibration Control Of Flexible Space Structures

Large flexible space structures will generate substantial vibrations for a long time when service in orbit, due to the lack of air damping in the space environment, under the external excitation. This phenomenon will affect the normal operation and the structure safety of the spacecraft. Through the piezoelectric damping system to control the vibration of flexible space structures is a feasible method. Piezoelectric materials have piezoelectric effect and advantages such as small size, light weight, fast response and so on, so it have broad application prospects in spacecraft of intelligent control and signal detection, etc. In this paper, we carried out experimental study on the vibration suppression of space flexible structures by using piezoelectric damping system, and simplified the problem for the passive vibration control of single rope to explore the basic problem. By adopting design and optimize the external piezoelectric damping system to study the vibration behavior of single rope for passive vibration control, and achieve the effect of energy absorption and vibration suppression.The main contents of this paper are as follows:Established the rigid-flexible coupling system by cantilever beam and soft cable combined with the scientific study, for the research of the damping effect of the coupling system by using piezoelectric damping system, with the structure and motion characteristics of the large flexible space structures as the reference. Considering the force electric coupling performance of the piezoelectric materials and the piezoelectric equation under different boundary conditions in the process of design piezoelectric damping system. And verified the positive and inverse piezoelectric effect of piezoelectric materials in vibration control of the initial application through experiments, the results show that: When put excitation at the end of the cantilever beam under free vibration, the piezoelectric patches pasted on the cantilever beam can produce dozens of millivolt to about 2 v voltage. If add the electric field to piezoelectric materials, the material under the effect of electric field can drive cantilever beam produce forced vibration for a long time.Analyzed the damping system of typical piezoelectric cantilever in theory, using the transfer function method to optimize the parameters of piezoelectric shunt damping circuit, obtained the optimal resistance value and the optimal inductance of RL series shunt circuit. In addition, researched the passive vibration control of cantilever beam-soft cable coupling system through the experiment. Verified the correctness of the theoretical analysis and the feasibility and effectiveness of RL series piezoelectric shunt damping system in structure vibration control.In order to further improve the damping efficiency, we optimized the synthetic inductance of piezoelectric damping system and reselected the optimal parameters of the coupling system. Selected the open and short circuit natural frequency of the coupling system in the process of vibration when calculated the optimal resistance value and the optimal inductance value. Experiments show that: the damping efficiency of piezoelectric damping system after optimization is higher than before.Finally, The negative capacitance piezoelectric damping system has been used to suppress the vibration of the coupling system, and the related parameters were optimized through theoretical calculation and numerical analysis. Experiments show that: the damping efficiency of negative capacitance method is higher than that of RL series piezoelectric shunt damping circuit in forced vibration on the whole.