Active-passive hybrid piezoelectric networks for vibration control: comparisons and improvement

In this research, the passive damping and active control authority of several basic active-passive hybrid piezoelectric networks are analysed and compared. The comparison is performed in a nondimensionalized manner, throughout which the importance of the generalized electro-mechanical coupling coefficient is highlighted. It is concluded that these configurations yield very similar open-loop performance for the same electro-mechanical coupling. It is shown that larger electro-mechanical coupling leads to higher passive network damping and, depending on the design and configuration, could also derive better active authority and overall performance. A method of increasing the electro-mechanical coupling coefficient by using a negative capacitance circuit is proposed, analysed and experimentally verified.