Chegury Viana F., Steffen Jr. V., Rade D.

In the context of passive noise and vibration control, the combination of piezoelectric patches combined with passive electric circuits (shunt circuits) has been regarded as a promissing strategy. Basically, it enables the dynamic strain energy to be converted into electrical energy and part of this energy can be dissipated in the electrical circuit. Various types of circuit topologies have been suggested such as resistive shunts and resistance-inductor shunts (also known as resonant shunts). A number of studies have demonstrated that resonant shunts are more efficient than resistive shunts. However, one of the main disadvantages of resonant shunts is related to the fact that their effective bandwidth is rather limited. This leads to the use of multimodal shunt circuits, which are much more elaborated, when broadband operation is intended. More recently, an active shunt technique for controlling vibration has been proposed by Behrens and co-workers, based on the concept of negative capacitance controller. While achieving comparable performance to that of other shunt topologies, the negative capacitance controller has some advantages, the most relevant of wich being its capacity of attenuating vibration amplitudes in a relatively large frequency band. In this paper, some relevant aspects of negative capacitance shunts are discussed, with emphasis placed on the design of such devices when applied to two-dimensional, plate-like structures. The study encompasses the analysis of two variants of electronic circuits and the modeling of plates combined with negative capacitance shunts. Numerical simulations and experimental tests are carried-out aiming at comparing the performance of negative capacitance and resonant shunts when used for multimodal broadband vibration attenuation.