Multiple electrically tunable parametric resonances in a capacitively coupled electromechanical resonator for broadband energy harvesting

We present a new concept of the thermoelectric structure that generates microwave and terahertz signals when illuminated by femtosecond optical pulses. The structure consists of a series array of capacitively coupled thermocouples. The array acts as a hybrid type microwave transmission line with anomalous dispersion and phase velocity higher than the velocity of light. This allows for adding up the responces from all the thermocouples in phase. The array is easily integrable with microstrip transmission lines. Dispersion curves obtained from both the lumped network scheme and numerical simulations are presented. The connection of the thermocouples is a composite right/left-handed transmission line, which can receive terahertz radiation from the transmission line ports. The radiation of the photon to the surface of the thermocouple structure causes a voltage difference with the bandwidth of terahertz. We examined a lossy composite right/left-handed transmission line to extract the circuit elements. The calculated properties of the design are extracted by employing commercial software package CST STUDIO SUITE.

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Analysis of magneto rheological elastomers for energy harvesting systems

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209350 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 439-446

Author(s):

Gildas Diguet ◽

Gael Sebald ◽

Masami Nakano ◽

Mickaël Lallart ◽

Jean-Yves Cavaillé

Keyword(s):

Magnetic Field ◽

Energy Harvesting ◽

Shear Strain ◽

Magnetic Induction ◽

Magnetic Particles ◽

Homogeneous Magnetic Field ◽

Electrical Signal ◽

Harvesting Systems ◽

Dc Bias ◽

Magneto Rheological

Magneto Rheological Elastomers (MREs) are composite materials based on an elastomer filled by magnetic particles. Anisotropic MRE can be easily manufactured by curing the material under homogeneous magnetic field which creates column of particles. The magnetic and elastic properties are actually coupled making these MREs suitable for energy conversion. From these remarkable properties, an energy harvesting device is considered through the application of a DC bias magnetic induction on two MREs as a metal piece is applying an AC shear strain on them. Such strain therefore changes the permeabilities of the elastomers, hence generating an AC magnetic induction which can be converted into AC electrical signal with the help of a coil. The device is simulated with a Finite Element Method software to examine the effect of the MRE parameters, the DC bias magnetic induction and applied shear strain (amplitude and frequency) on the resulting electrical signal.

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Simply supported FPEDs connected by springs for broadband energy harvesting

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209323 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 201-210

Author(s):

Yoshikazu Tanaka ◽

Satoru Odake ◽

Jun Miyake ◽

Hidemi Mutsuda ◽

Atanas A. Popov ◽

...

Keyword(s):

Energy Harvesting ◽

Evaluation Method ◽

Energy Harvester ◽

Vibrational Energy ◽

Functional Materials ◽

Vibration Energy ◽

Theoretical Evaluation ◽

Vibration Energy Harvester ◽

Polyvinylidene Difluoride ◽

Simply Supported

Energy harvesting methods that use functional materials have attracted interest because they can take advantage of an abundant but underutilized energy source. Most vibration energy harvester designs operate most effectively around their resonant frequency. However, in practice, the frequency band for ambient vibrational energy is typically broad. The development of technologies for broadband energy harvesting is therefore desirable. The authors previously proposed an energy harvester, called a flexible piezoelectric device (FPED), that consists of a piezoelectric film (polyvinylidene difluoride) and a soft material, such as silicon rubber or polyethylene terephthalate. The authors also proposed a system based on FPEDs for broadband energy harvesting. The system consisted of cantilevered FPEDs, with each FPED connected via a spring. Simply supported FPEDs also have potential for broadband energy harvesting, and here, a theoretical evaluation method is proposed for such a system. Experiments are conducted to validate the derived model.

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