Piezoelectric shunting parameter estimation using electrical impedance models

초록

In this paper, a passive damping enhancement of piezo-electric smart structures is studied. A conventional parameter tuning method of the passive damping using piezoelectric smart materials, so called a mechanical vibration absorber method, is reviewed and a new method for determining the optimal shunting parameters using electric impedance is developed. Piezoelectric smart materials convert mechanical energy induced by vibration of structure into electrical energy via the mechanism of piezo-electricity and this electrical energy is dissipated through connected load impedance, which is namely piezo-electric damping. The electric impedance method is to determine the optimal parameters by maximizing the dissipated energy at the load resistor. To see the validity of this approach, the electric impedance based analysis of mechanical vibration absorber is presented and the shunting parameters by this method show a good agreement with those of mechanical vibration absorber tuning method. A piezo-electric cantilevered beam for single mode shunt and plate for multiple-mode shunt are taken as examples of real structure and the proposed method is applied with the measured electric impedance. The simulation and experiment are conducted and they show a vibration reduction at targeted mode. This method can be applied to arbitrary piezoelectric smart structures such that it will increase the feasibility of smart structures for reducing noise and vibrations.