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1

Time-slot based architecture for power beam-assisted relay techniques in CR-WSNs with transceiver hardware inadequacies

Umer Mushtaq Muhammad, Jiang Hong, Zhang Qiuyun, Manlu Liu, Muhammad Owais

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 5

art. no. e146620

EN

Over the past two decades, numerous research projects have concentrated on cognitive radio wireless sensor networks (CR-WSNs) and their benefits. To tackle the problem of energy and spectrum shortfall in CR-WSNs, this research proposes an underpinning decode-&-forward (DF) relaying technique. Using the suggested time-slot architecture (TSA), this technique harvests energy from a multi-antenna power beam (PB) and delivers source information to the target utilizing energy-constrained secondary source and relay nodes. The study considers three proposed relay selection schemes: enhanced hybrid partial relay selection (E-HPRS), conventional opportunistic relay selection (C-ORS), and leading opportunistic relay selection (L-ORS). We present evidence for the sustainability of the suggested methods by examining the outage probability (OP) and throughput (TPT) under multiple primary users (PUs). These systems leverage time switching (TS) receiver design to increase end-to-end performance while taking into account the maximum interference constraint and transceiver hardware inadequacies. In order to assess the efficacy of the proposed methods, we derive the exact and asymptotic closed-form equations for OP and TPT & develop an understanding to learn how they affect the overall performance all across the Rayleigh fading channel. The results show that OP of the L-ORS protocol is 16% better than C-ORS and 75% better than E-HPRS in terms of transmitting SNR. The OP of L-ORS is 30% better than C-ORS and 55% better than E-HPRS in terms of hardware inadequacies at the destination. The L-ORS technique outperforms C-ORS and E-HPRS in terms of TPT by 4% and 11%, respectively.

2

Mechanical vibrations: recent trends and engineering applications

Garus Sebastian, Błachowski Bartłomiej, Sochacki Wojciech, Jaskot Anna, Kwiatoń Paweł, Ostrowski Mariusz, Šofer Michal, Kapitaniak Tomasz

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2022

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Vol. 70, nr 1

art. no. e140351

EN

Although the study of oscillatory motion has a long history, going back four centuries, it is still an active subject of scientificr esearch. In this review paper prospective research directions in the field of mechanical vibrations were pointed out. Four groups of important issues in which advanced research is conducted were discussed. The first are energy harvester devices, thanks to which we can obtain or save significant amounts of energy, and thus reduce the amount of greenhouse gases. The next discussed issue helps in the design of structures using vibrations and describes the algorithms that allow to identify and search for optimal parameters for the devices being developed. The next section describes vibration in multi-body systems and modal analysis, which are key to understanding the phenomena in vibrating machines. The last part describes the properties of granulated materials from which modern, intelligent vacuum-packed particles are made. They are used, for example, as intelligent vibration damping devices.

3

Design of nonlinear electromagnetic energy harvester equipped with mechanical amplifier and spring bumpers

Ostrowski M., Błachowski B., Bocheński M., Piernikarski D., Filipek P., Janicki W.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2020

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Vol. 68, nr 6

1373--1383

EN

The main drawback of vibration-based energy harvesting is its poor efficiency due to small amplitudes of vibration and low sensitivity at frequencies far from resonant frequency. The performance of electromagnetic energy harvester can be improved by using mechanical enhancements such as mechanical amplifiers or spring bumpers. The mechanical amplifiers increase range of movement and velocity, improving also significantly harvester efficiency for the same level of excitation. As a result of this amplitude of motion is much larger comparing to the size of the electromagnetic coil. This in turn imposes the need for modelling of electromagnetic circuit parameters as the function of the moving magnet displacement. Moreover, high velocities achieved by the moving magnet reveal nonlinear dynamics in the electromagnetic circuit of the energy harvester. Another source of nonlinearity is the collision effect between magnet and spring bumpers. It has been shown that this effect should be carefully considered during design process of the energy harvesting device. The present paper investigates the influence of the above-mentioned nonlinearities on power level generated by the energy harvester. A rigorous model of the electromagnetic circuit, derived with aid of the Hamilton’s principle of the least action, has been proposed. It includes inductance of the electromagnetic coil as the function of the moving magnet position. Additionally, nonlinear behaviour of the overall electromagnetic device has been tested numerically for the case of energy harvester attached to the quarter car model moving on random road profiles. Such a source of excitation provides wide band of excitation frequencies, which occur in variety of real-life applications.

4

Investigation of Electrical Properties for Cantilever-Based Piezoelectric Energy Harvester

Ali Ahsan, Pasha Riffat Asim, Sheeraz Muhammad Abdullah, Butt Zubair, Elahi Hassan, Khan Afzaal Ahmed

Advances in Science and Technology. Research Journal

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2019

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Vol. 13, no 3

76--85

EN

In the present era, the renewable sources of energy, e.g., piezoelectric materials are in great demand. They play a vital role in the field of micro-electromechanical systems, e.g., sensors and actuators. The cantilever-based piezoelectric energy harvesters are very popular because of their high performance and utilization. In this research-work, an energy harvester model based on a cantilever beam with bimorph PZT-5A, having a substrate layer of structural steel, was presented. The proposed energy scavenging system, designed in COMSOL Multiphysics, was applied to analyze the electrical output as a function of excitation frequencies, load resistances and accelerations. Analytical modeling was employed to measure the output voltage and power under pre-defined conditions of acceleration and load resistance. Experimentation was also performed to determine the relationship between independent and output parameters. Energy harvester is capable of producing the maximum power of 1.16 mW at a resonant frequency of 71 Hz under 1g acceleration, having load resistance of 12 kΩ. It was observed that acceleration and output power are directly proportional to each other. Moreover, the investigation conveys that the experimental results are in good agreement with the numerical results. The maximum error obtained between the experimental and numerical investigation was found to equal 4.3%.

5

Effective harvesting of braking energy in electric cars

Trzaska Z.

Journal of KONES

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2018

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Vol. 25, No. 1

407--422

EN

Regenerative braking and damping are effective approaches for electric cars to extend their driving range. A disk Faraday generator regenerative braking strategy integrated with controlled charging of a supercapacitor is developed in this article to advance the level of energy-savings on the car board. The kinetic energy of the car suspension during driving regenerated effectively to electric energy by using shock absorber is harvested and then used to charge the vehicle’s battery, the power electronics and the supercapacitor. One of the advantages of supercapacitors is their high power capability, which is applicable for high rate of charging and discharging operations like motor starting and regenerative braking of an electric vehicle. This article presents a new charging method for supercapacitors. Common for regenerative braking and damping chargers for supercapacitors are usually equipped with electronic PWM converter performing two states of operation per switching cycle. A simple open-loop control system is applicable for the whole charging state. The proposed circuit consists of a minimum number of components. It is free of stability problem and protects itself from being overloaded by supercapacitor with zero initial charge. Simulation results for regenerative braking processes corresponding to three velocity tests are included.

6

Lead free Ba0.85Ca0.15TiO3 piezoelectric transformer for energy harvesting application

Kozielski L., Feliksik K., Wodecka-Duś B.

Materiały Ceramiczne

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2017

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T. 69, nr 2

68--72

EN

Piezoelectric Transformers are utilized to boost the conversion of mechanical vibration energy into electrical power with considerable potential in Energy Harvesting applications. Nowadays however, the critical challenge that need to be addressed is the use of lead free materials for their construction. The other requirements include the high conversion ratio, small size and reasonable power density. This work, for the first time, proposes implementation of the lead free Ba0.85Ca0.15TiO3 material for a piezoelectric transformer that is designed for a vibration energy collection device.

PL

Transformatory piezoelektryczne wykorzystywane są w celu zwiększenia efektywności konwersji energii drgań mechanicznych w energię elektryczną z dużym potencjałem w zastosowaniach do zbierania energii z otoczenia. Obecnie jednak kluczowe wyzwanie, które należy rozwiązać, polega na wykorzystaniu bezołowiowego, ceramicznego materiału piezoelektrycznego do jego budowy. Pozostałe wymagania obejmują wysoki współczynnik konwersji, mały rozmiar i rozsądną gęstość mocy. Praca ta po raz pierwszy proponuje zastosowanie bezołowiowej ceramiki Ba0.85Ca0.15TiO3 w transformatorze piezoelektrycznym, zaprojektowanym do urządzenia do zbierania energii wibracyjnej.

7

Development board of the autonomous semi-passive RFID transponder

Jankowski-Mihułowicz P., Węglarski M., Pitera G., Kawalec D., Lichoń W.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2016

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Vol. 64, nr 3

647--654

EN

The idea of multiband development board designed to support and advance the technique of battery-less autonomous semi-passive RFID transponders is presented in the paper. The extra function of harvesting energy from the electromagnetic field of different radio communications systems, the ultra efficient power conditioner and the energy storage block are applied in the proposed construction. The facility of utilizing gathered energy is provided to support designers in developing applications of automatic object identification. Since the evaluation board is to work without a galvanic cell, the particular emphasis is put on the mechanisms that improve energy efficient operation of the whole electronic circuit. The construction principles and operation modes (charging, cold start, sleep with charging, sleep, measurement and cut-off) of the storage unit are described in depth in the paper. The preproduction batch of the demonstrators has been manufactured on automated assembly line at ELMAK Ltd. Company, according to the elaborated model. It confirms that the author’s demonstrator of the battery-less autonomous semi-passive transponder can be reproduced on an industrial scale. On the basis of the preproduction series, the performance parameters of the final product have been estimated. The presented study should significantly contribute to the RFID technique therefore the authors set up the evaluation process of marketing research and product commercialization.

8

Propozycje zastosowania czujników samozasilających się w przemyśle wydobywczym

Jasiulek D.

Przegląd Górniczy

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2014

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T. 70, nr 1

9--15

PL

W artykule przedstawiono perspektywę zastosowania czujników samozasilających się, wykorzystujących energię drgań lub energię cieplną do monitorowania wybranych parametrów maszyn górniczych. Obecnie, szczególnie w zakresie monitorowania maszyn i inteligentnych budynków, coraz częściej stosowane są czujniki z „auto-zasilaniem”. Sensory do zasilania swoich struktur wykorzystują zjawiska fizyczne, takie jak: przepływ ciepła, energię drgań lub światła (ang. energy harvesting – pozyskiwanie energii). Analiza takich rozwiązań wykazała, że istnieją możliwości zastosowania tej technologii w systemach automatyki oraz diagnostyki maszyn i urządzeń górniczych. W artykule przedstawiono perspektywy wdrożenia systemu czujników samozasilających w odniesieniu do maszyn stosowanych w przestrzeniach zagrożonych wybuchem metanu i/lub pyłu węglowego.

EN

This paper presents the prospects of application of self-energizing sensors which use the point or thermal energy to monitor selected parameters of mining machines. Currently, more and more often mainly in monitoring of machines and Building Management Systems (intelligent buildings) there are self-energizing sensors applied. The sensors use the following physical phenomena to reinforce their structures: flow of heat, point or light energy. Analysis of such solutions shows there are possibilities to apply this technology in automation systems and diagnostics of machines and mining equipment. This paper presents the prospect of implementation of self-energizing sensor systems in relation to the machines used in areas prone to methane and/or coal dust explosion.

9

Wykorzystanie układu LTC3588-1 jako źródła pozyskiwania energii resztkowej

Tyborczyk S., Galla S.

Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej

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2013

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Nr 36

171--174

PL

Przedmiotem niniejszej pracy są zagadnienia odzyskiwania energii resztkowej generowanej wskutek mechanicznego odkształcania kryształu piezoelektrycznego oraz za pomocą ogniwa fotowoltaicznego przy zastosowaniu przetwornicy napięcia typu LTC3588-1. Zastosowana przetwornica umożliwia pozyskiwanie energii z różnych źródeł. W ramach referatu przedstawiono wyniki pracy nad mikrozasilaczem, który umożliwiał zarówno współpracę z piezoelektrykami jak i ogniwami fotowoltaicznymi

EN

The object of this paper are issues related to the recovery of the residual energy generated by the mechanical deformation of the piezoelectric crystal or by the use of a photovoltaic cell using a specialized LTC3588-1 voltage converter. The applied converter allows to use various energy source.