http://www.rmorais.utad.pt/RMPDFFiles/PDFPapers/WANG06.pdf

Review: Wireless sensors in agriculture and food industry-Recent development and future perspective

Advances in materials, mechanics, and manufacturing now allow construction of high-quality electronics and optoelectronics in forms that can readily integrate with the soft, curvilinear, and time-dynamic surfaces of the human body. The resulting capabilities create new opportunities for studying disease states, improving surgical procedures, monitoring health/wellness, establishing human-machine interfaces, and performing other functions. This review summarizes these technologies and illustrates their use in forms integrated with the brain, the heart, and the skin.

https://www.annualreviews.org/doi/pdf/10.1146/annurev-bioeng-071811-150018

Flexible and Stretchable Electronics for Biointegrated Devices

A review of wireless sensors and networks' applications in agriculture

Strategies for extracting the three-phase reference currents for shunt active power filters are compared, evaluating their performance under different source and load conditions with the new IEEE Standard 1459 power definitions. The study was applied to a three-phase four-wire system in order to include imbalance. Under balanced and sinusoidal voltages, harmonic cancellation and reactive power compensation can be attained in all the methods. However, when the voltages are distorted and/or unbalanced, the compensation capabilities are not equivalent, with some strategies unable to yield an adequate solution when the mains voltages are not ideal. Simulation and experimental results are included

/pdf/comparison-of-control-strategies-for-shunt-active-power-2h9dyoalqf.pdf

Comparison of Control Strategies for Shunt Active Power Filters in Three-Phase Four-Wire Systems

Thermoelectric (TE) materials have the capability of converting heat into electricity, which can improve fuel efficiency, as well as providing robust alternative energy supply in multiple applications by collecting wasted heat, and therefore, assisting in finding new energy solutions. In order to construct high performance TE devices, superior TE materials have to be targeted via various strategies. The development of high performance TE devices can broaden the market of TE application and eventually boost the enthusiasm of TE material research. This review focuses on major novel strategies to achieve high-performance TE materials and their applications. Manipulating the carrier concentration and band structures of materials are effective in optimizing the electrical transport properties, while nanostructure engineering and defect engineering can greatly reduce the thermal conductivity approaching the amorphous limit. Currently, TE devices are utilized to generate power in remote missions, solar-thermal systems, implantable or/wearable devices, the automotive industry, and many other fields; they are also serving as temperature sensors and controllers or even gas sensors. The future tendency is to synergistically optimize and integrate all the effective factors to further improve the TE performance, so that highly efficient TE materials and devices can be more beneficial to daily lives.

https://espace.library.uq.edu.au/view/UQ:722903/UQ722903_OA.pdf

High Performance Thermoelectric Materials: Progress and Their Applications

Due the intensive use of power converters and other non-linear loads in industry and by consumers in general, it can be observed an increasing deterioration of the power systems voltage and current waveforms. The presence of harmonics in the power lines results in greater power losses in distribution, interference problems in communication systems and, sometimes, in operation failures of electronic equipments, which are more and more sensitive since they include microelectronic control systems, which work with very low energy levels. Because of these problems, the issue of the power quality delivered to the end consumers is, more than ever, an object of great concern. International standards concerning electrical power quality (IEEE-519, IEC 61000, EN 50160, among others) impose that electrical equipments and facilities should not produce harmonic contents greater than specified values, and also specify distortion limits to the supply voltage. Meanwhile, it is mandatory to solve the harmonic problems caused by those equipments already installed. Passive filters have been used as a solution to solve harmonic current problems, but they present several disadvantages, namely: they only filter the frequencies they were previously tuned for; their operation cannot be limited to a certain load; resonances can occur because of the interaction between the passive filters and other loads, with unpredictable results. To cope with these disadvantages, recent efforts have been concentrated in the development of active filters.

https://repositorium.sdum.uminho.pt/bitstream/1822/1921/1/IEEE-IES-Newsletter-00.pdf

Active filters with control based on the p-q theory

http://dei-s1.dei.uminho.pt/pessoas/lgoncalves/LostLink/2009/Thermoelectric%20Thin-Films%20LMGoncalves.pdf

Optimization of thermoelectric properties on Bi2Te3 thin films deposited by thermal co-evaporation

The experimental validation of a novel architecture of an off-board, three-phase fast battery charger for electric vehicles (EVs) with innovative operation modes is presented in this paper. The proposed EV fast battery charger is based on a dual-stage power converter (ac-dc and dc-dc) sharing the same dc link. The ac-dc stage is used as an interface between the power grid and the dc link. It is composed of the parallel association of two full-bridge voltage-source converters, and allows control of the grid current and of the dc-link voltage. The dc-dc stage is used as an interface between the dc link and the batteries. It is constituted by a bidirectional three-level asymmetrical voltage-source converter, and controls the flux of current during the EV battery charging process. Compared with the traditional solutions used for EV fast battery chargers, the proposed architecture operates as an interleaved converter, facilitating the reduction of the passive filters size, and the grid current harmonic distortion for the same switching frequency. Throughout the paper, the ac-dc and dc-dc stages, and the digital control algorithms are described in detail. The experimental validation was performed in a laboratory using a developed EV fast battery charger prototype, operating through the grid-to-vehicle and the proposed charger-to-grid modes, exchanging active, and reactive power with the power grid.

/pdf/experimental-validation-of-a-novel-architecture-based-on-a-3ammegom4e.pdf

Experimental Validation of a Novel Architecture Based on a Dual-Stage Converter for Off-Board Fast Battery Chargers of Electric Vehicles

The present work reports on the fabrication and characterization of a planar Peltier cooler on a flexible substrate. The device was fabricated on a 12 µm thick Kapton(c) polyimide substrate using Bi2Te3 and Sb2Te3 thermoelectric elements deposited by thermal co-evaporation. The cold area of the device is cooled with four thermoelectric junctions, connected in series using metal contacts. Plastic substrates add uncommon mechanical properties to the composite film–substrate and enable integration with novel types of flexible electronic devices. Films were deposited by co-evaporation of tellurium and bismuth or antimony to obtain Bi2Te3 or Sb2Te3, respectively. Patterning of the thermoelectric materials using lift-off and wet-etching techniques was studied and compared. The performance of the Peltier microcooler was analysed by infrared image microscopy, on still-air and under vacuum conditions, and a maximum temperature difference of 5 °C was measured between the cold and the hot sides of the device.

/pdf/fabrication-of-flexible-thermoelectric-microcoolers-using-3o2827llbq.pdf

Fabrication of flexible thermoelectric microcoolers using planar thin-film technologies

This paper presents the development of an on-board bidirectional battery charger for Electric Vehicles (EVs) targeting Grid-to-Vehicle (G2V), Vehicle-to-Grid (V2G), and Vehicle-to-Home (V2H) technologies. During the G2V operation mode the batteries are charged from the power grid with sinusoidal current and unitary power factor. During the V2G operation mode the energy stored in the batteries can be delivered back to the power grid contributing to the power system stability. In the V2H operation mode the energy stored in the batteries can be used to supply home loads during power outages, or to supply loads in places without connection to the power grid. Along the paper the hardware topology of the bidirectional battery charger is presented and the control algorithms are explained. Some considerations about the sizing of the AC side passive filter are taken into account in order to improve the performance in the three operation modes. The adopted topology and control algorithms are accessed through computer simulations and validated by experimental results achieved with a developed laboratory prototype operating in the different scenarios.

/pdf/bidirectional-battery-charger-with-grid-to-vehicle-vehicle-xevpumyg3b.pdf

Carlos Couto

Papers

Active filters with control based on the p-q theory

Optimization of thermoelectric properties on Bi2Te3 thin films deposited by thermal co-evaporation

Experimental Validation of a Novel Architecture Based on a Dual-Stage Converter for Off-Board Fast Battery Chargers of Electric Vehicles

Fabrication of flexible thermoelectric microcoolers using planar thin-film technologies

Bidirectional battery charger with Grid-to-Vehicle, Vehicle-to-Grid and Vehicle-to-Home technologies