A Review of MEMS Scale Piezoelectric Energy Harvester

Abstract

Piezoelectric energy harvester (PEH) is emerging as a novel device which can convert mechanical energy into electrical energy. It is mainly used to collect ambient vibration energy to power sensors, chips and some other small applications. This paper first introduces the working principle of PEH. Then, the paper elaborates the research progress of PEH from three aspects: piezoelectric materials, piezoelectric modes and energy harvester structures. Piezoelectric material is the core of the PEH. The piezoelectric and mechanical properties of piezoelectric material determine its application in energy harvesting. There are three piezoelectric modes, d 31 , d 33 and d 15 , the choice of which influences the maximum output voltage and power. Matching the external excitation frequency maximizes the conversion efficiency of the energy harvester. There are three approaches proposed in this paper to optimize the PEH's structure and match the external excitation frequency, i.e., adjusting the resonant frequency, frequency up-converting and broadening the frequency bandwidth. In addition, harvesting maximum output power from the PEH requires impedance matching. Finally, this paper analyzes the above content and predicts PEH's future development direction.

Electromechanical Modeling of MEMS-Based Piezoelectric Energy Harvesting Devices for Applications in Domestic Washing Machines

“…Finally, the deflections of both PEH devices at resonance can be approximated using Qa times the static deflections ( ) [27]: The bending moment function for each section of both PEH devices was determined through the Equation (20). The bending moment function for the first section, x (0,L s1 ), and for the second section, x (L s1 ,L s12 ), are given by Equations (21) and (22), respectively:…”

“…The PEH devices have emerged in recent years due to the possibility of integration with MEMS [16][17][18]. For instance, several researchers have developed MEMS-based PEH devices for different applications [19][20][21][22]. Lu et al [23] reported a numerical modeling of a PEH cantilever for MEMS applications.…”

Advances in Mechanical Systems Dynamics

“…In recent years the interest in vibration has increased, owing to the rapid development of vibration energy harvesting technologies [16]. However, vibrations are also a potential problem for any application that includes moving components [17].…”

Simple and Efficient AlN-Based Piezoelectric Energy Harvesters

“…Electrostatic and electromagnetic induction, and piezoelectricity can all typically be exploited as transducing mechanisms to convert mechanical energy into electrical [4]. However, from these, piezoelectric energy harvesters (PEHs) exhibit high-energy density and are, therefore, more suitable for practical applications [5]. Moreover, piezoelectric materials have an inherent capability to directly convert mechanical stress/strain energy into electrical energy, therefore, such devices are compact and possess simpler designs, compared to their electromagnetic and electrostatic counterparts.…”