Shunted Piezoceramics for Vibration Damping – Modeling, Applications and New Trends

Piezoelectric shunt damping is a well known technique to damp the vibrations of mechanical structures. This technique relies on the piezoelectric effect that converts mechanical energy into electrical energy. A damping effect on the host structure is observed when the electrical energy is dissipated. In order to optimize the damping performance, the transferred energy as well as the dissipated energy must be maximized. The transferred energy depends on the piezoelectric constants as well as the vibration mode and the location of the piezoelements within the structure. While higher piezoelectric constants generally increase the amount of transferred energy, the location can typically only be optimized for one eigenform of the structure. As a consequence, the piezoelectric transducer can be placed in such a way that it only affects one eigenform of the system. One measure for the coupling of the piezoceramics is the generalized coupling coefficient, which is defined for every vibration mode and generally takes different values for the individual modes. The design of the electrical shunt aims at maximizing the energy dissipation. Different networks have been developed, which can be classified into the categories passive, active, linear or non-linear. The best choice of network depends on the performance target, the availability of electrical power supply and the vibration behavior and excitation type of the mechanical structure.