Design and Optimization of a Multimode Low-Frequency Piezoelectric Energy Harvester

In this paper, we present a microelectromechanical systems (MEMS)-based multimode low-frequency piezoelectric energy harvester (PEH), which can operate at low resonant frequencies (i.e., [Formula: see text][Formula: see text]Hz). The proposed harvester has a symmetric serpentine structure with a doubly clamped configuration comprising several proof masses at the junctions. The optimal parameters of the proposed energy harvester are determined by a computerized optimization technique based on a genetic algorithm (GA). Finite element simulations showed that the optimization results can generate high voltage with two usable low-frequency resonant frequencies. Furthermore, we discuss the array structure based on the proposed PEH. Finite element simulations demonstrate that our piezoelectric MEMS harvester array can generate voltage with a frequency ranging from 110.95 to 157.84[Formula: see text]Hz. Its normalized power density (NDP) when operating in the first four modes is 1284, 932, 1978, and 2592 [Formula: see text]Wcm −3 m −2 s 4 , respectively, and its performance outperforms those of previously reported MEMS-based energy harvesters.