Nonlinear piezoelectricity and damping in partially-covered piezoelectric cantilever with self-sensing synchronized switch damping on inductor circuit

摘要

We examined a partially covered piezoelectric cantilever connected to a self-sensing synchronized switch damping on an inductor (SSDI) circuit. Nonlinear behavior, which cannot be explained by the single-degree-of-freedom model based on linear piezoelectricity, is observed in the frequency response as the excitation level increases. Here, we propose a new method that allows us to predict the attenuation performance in such a smart damping structure. We first derived the governing equation for a practical cantilever structure in which the piezoelectric elements are attached with glue and partially cover the cantilever. We include the nonlinear piezoelectricity and damping in the model. Then, we used a two-way coupled simulation technique to investigate the complex electromechanical dynamics for the piezoelectric cantilever connected to the self-sensing SSDI circuit. Our model replicates the nonlinear behavior observed experimentally. Intriguingly, the simulation revealed that, when connected to the SSDI circuit, the lower shift of the peak frequency observed in the open circuit vanished and the peak frequency shifted to higher frequency because of the increased piezoelectric coupling force. We emphasize the importance of nonlinear piezoelectricity and damping in the model and show that ignoring the peak frequency shift and the decrease in the displacement may lead to the wrong estimation in the attenuation performance, especially as the excitation level increases.