Array of piezoelectric energy harvesters

Abstract

This article analyzes the electrical behavior of an array of piezoelectric energy harvesters endowed with several interfacing circuits, including the standard AC/DC circuit and parallel/series SSHI (synchronized switch harvesting on inductor) circuits. The harvesters are classified according to the connection to a single or multiple rectifiers. The analytic estimates of harvested power are derived explicitly for different cases. The results show that DC power output changes from the power-boosting mode to the wideband mode according to various degrees of differences in the parameters of harvesters. In particular, the system with multiple rectifiers exhibits more bandwidth improvement than that with a single rectifier. Finally, it is shown that the electrical performance of an SSHI array system enjoys both power boosting and bandwidth improvement.