Efficiency of energy conversion by piezoelectrics

The efficiency of energy conversion by piezoelectric devices depends upon the quality factor Q and electromechanical coupling coefficient k(2). In this study the efficiency Q and k(2) are measured for a piezoelectric cantilever, a piezoelectric stack, and a micromachined piezoelectric membrane. The experimental values are compared to a model which predicts efficiency at resonance in terms of k(2) and Q. Results of the experiment and model are within 2% of each other. (c) 2006 American Institute of Physics.