A Low-Frequency MEMS Piezoelectric Energy Harvesting System Based on Frequency Up-Conversion Mechanism

Abstract

This paper proposes an impact-based micro piezoelectric energy harvesting system (PEHS) working with the frequency up-conversion mechanism. The PEHS consists of a high-frequency straight piezoelectric cantilever (SPC), a low-frequency S-shaped stainless-steel cantilever (SSC), and supporting frames. During the vibration, the frequency up-conversion behavior is realized through the impact between the bottom low-frequency cantilever and the top high-frequency cantilever. The SPC used in the system is fabricated using a new micro electromechanical system (MEMS) fabrication process for a piezoelectric thick film on silicon substrate. The output performances of the single SPC and the PEHS under different excitation accelerations are tested. In the experiment, the normalized power density of the PEHS is 0.216 μW·g−1·Hz−1·cm−3 at 0.3 g acceleration, which is 34 times higher than that of the SPC at the same acceleration level of 0.3 g. The PEHS can improve the output power under the low frequency and low acceleration scenario.

Characterizing and Optimizing Piezo Harvesters for Train Interiors

“…This effect can be derived by the equations in Strain-Charge form [6] [7]. The majority of piezoelectric generators that have been fabricated and tested use some variation of lead zirconate titanate (PZT), because its large piezoelectric coefficient and dielectric constant allows generating more power for a given input acceleration [7] [8] [9]. In this paper, we provide the measurement and test done with a laminated piezo sensor manufactured by 'TE Connectivity'.…”

“…The first-order resonant frequency of the cantilever can be adjusted by keeping a mass on the free end of the cantilever [12] [13]. The resonant frequency can be calculated either using 'Euler-Bernoulli' beam equations or by a first-order spring-mass system with corresponding stiffness and effective mass [7], [14]. The mass weight is calculated as shown in Eq.…”

A Wideband Magnetic Frequency Up‐Converter Energy Harvester

“…[ 25 ] The first four designs use PZT as a transducer instead of PVDF, which compromises the devices’ durability, as PZT is fragile. [ 26–30 ] They also have a low normalized bandwidth of operation. The fifth architecture uses PVDF and offers a high normalized bandwidth utilizing multiple magnets for the frequency up‐conversion, allowing extremely LFs to be detected and up‐converted.…”

A Review of Piezoelectric Vibration Energy Harvesting with Magnetic Coupling Based on Different Structural Characteristics

“…In general, the performance of linear piezoelectric energy harvesting is limited to a very narrow frequency bandwidth [ 18 , 19 , 20 ]. So, many methods have been proposed to realize broadband energy harvesting and improve energy-harvesting efficiency, including multimodal [ 21 , 22 ], frequency tuning [ 23 , 24 , 25 ], frequency-up [ 26 , 27 , 28 , 29 ], nonlinear approaches [ 30 , 31 , 32 , 33 , 34 ], etc. In addition, the design of new piezoelectric materials, such as organic–inorganic nanocomposites, is a promising strategy for improving the energy-conversion efficiencies.…”