Search

Triboelectric nanogenerators (TENGs) have been introduced as a rational and effective way of powering the low consuming electronic devices and sensors. Mostly these nanogenerators are manufactured using costly materials and complex fabrication processes that restrict their usage especially in developing countries. In this paper, we have presented an inexpensive and facile TENG for powering the environmental sensor. Readily available and cost-effective materials were used for manufacturing TENG like paper, thread sealant PTFE tape, and pencil. The manufactured paper based TENG produced short circuit current and open circuit voltage of $110\ \mu \mathrm{A}$ and 234 V respectively. The maximum power density of $96.22\ \mu \mathrm{W} /$ cm2 was achieved at 5 M $\Omega$. The rectified signal from TENG was used to charge a capacitor array of $300\ \mu \mathrm{F}$ which was successively used to power the environmental sensor. Temperature and humidity can be measured by powering the environmental sensor with the help of the proposed TENG. This facile and cost-effective TENG can be easily manufactured and deployed in resource limited environment for self-powered sensing systems.

In order to realize smart factory which is appeared in the concepts of Society 5.0 and Industry 4.0, wireless Internet of Things (IoT) becomes a key technology. Inside of the factory, there are heavy DATA traffics exist between moving/movable machine tools/robots/automated guided vehicle (AGV) with wireless access point (AP) and high speed moving/rotating objects/materials with wireless sensor node (SN). Currently, wireless systems used for wireless IoT are limited such as wireless-LAN/Bluetooth/RFID. Since these system’s frequency bands are limited and narrow, the interference between these systems becomes severe. In this paper, we propose a simplified beam forming wireless IoT communication using novel Wi-Fi backscatter system to notify the existence of SN who wants to send its DATA to AP. For Wi-Fi AP with beamforming function, knowing the numbers of existing SNs in each beam area will be a help for efficient beam control. This paper describes the Wi-Fi backscatter system in which the SNs backscatter the Wi-Fi signal transmitted from the AP then the AP detects the backscatter signals from SNs and know the existing SN’s number in its beam area. Since this backscatter system uses Wi-Fi modulated signal, the separation of SNs’ backscatter signals from AP’s transmitting Wi-Fi signal becomes complicated. This paper also describes the transceiver architecture of AP which reduces the complexity of signal processing and improves the dynamic range of reception.

As the demand for low-carbon and eco-friendly energy is increasing and the use of wearable devices is soaring, the triboelectric nanogenerator (TENG), which can economically harvest energy, is in the spotlight. Among many materials, paper is considered a promising substrate and frame material for self-powered TENG due to its high accessibility, flexibility, and biocompatibility. Here, we present a new structure of foldable paper based TENG (FP-TENG) composed of paper and PTFE/Si-rubber. The double-folded FP-TENG generates voltages and currents of 153 V and 2.2 µA, respectively, and shows excellent durability without signal degradation under 5,000 cycles of external force. A watch strap was manufactured with FP-TENG and integrated with an electronic watch pannel to supply power, and several LEDs were turned on. Therefore, FP-TENG is expected to be utilized as a promising eco-friendly energy source for small electronic devices.

International audience; The design of a dipole antenna printed on a paper substrate is presented in this paper. The antenna which integrates a compact balun is devoted for dual-band 2.4/5 GHz WLAN applications. The antenna is based on a double-side printed multilayer paper substrate and is fed with a coaxial cable for the testing. The simulated results of the whole structure are also presented in detail and compared with the measured performances.

As a material, cellulose/paper has attracted significant attention for its fibrous and bendable properties. Paper is a renewable resource with the most common forms coming from trees. This brief article describes efforts to create electronics "on" and "in" paper. Examples of electronics on paper include touch sensors and cold plasma-based sanitizers. The skin-like touch sensors use capacitance and patterned resistive networks for passive, scalable sensing with a reduced number of interconnects. When touched or wetted with water, the interdigitated electrodes in the resistive networks detect significant changes in electrical impedance. The plasma generators with layered and patterned sheets of paper use a simple and flexible format for dielectric barrier discharge to create atmospheric plasma without an applied vacuum. Examples of electronics in paper include sheets with tunable electrical conductivity and piezoresistive force sensors, along with functionalized paper-based electrodes capable of detecting small proteins and clinically relevant biomarkers. These papertronic devices have the potential to supply multi-functionality to new forms of smart bandages, skin-like sensing, food packaging, and robotic sensing and actuation.

The traditional space telemetry, tracking, command and communication system works in the radio frequency band. With the improvement on measurement accuracy and communication capacity in space missions, the traditional means have a certain bottleneck in dealing with the development of future space missions. The inherent lightweight, high parallel, high capacity and fine processing capabilities of Optics and microwave photonics show the potential to solve the above problems. This paper summarizes the innovative work of the Southwest China Institute of Electronic Technology in the application of laser measurement and communication integration, microwave photonic RF front-end technology in space telemetry, tracking, command and communication system. The experimental platform is established for verification, the accuracy of ranging and velocity measurement reaches millimeter level at 10Gbps single channel transmission rate with 1E-9 bit error rate under a simulation satellite-ground link. The microwave photonic RF front-end can be compatible with S to Ka band, with a sampling rate of 20Gsps and a signal bandwidth of 5GHz. It is expected to be applied to next generation of space telemetry, tracking, command and communication system or navigation and relay system.

As opposed to multiple-antenna solutions, in-band full-duplex (IBFD) systems can utilize a shared antenna for signal transmission and reception to reduce the device form factor. These single-antenna designs, however, must additionally consider the self-interference (SI) that is generated by antenna impedance-mismatch reflections. This paper investigates the effect of different antenna loads and transmission line lengths for commercially-available magnetic circulator and omnidirectional antenna components operating between 2 and 6 GHz. The results indicate that both the load impedance and the distance between the antenna and interface device can drastically impact the composite SI frequency-selectivity, which influences the overall IBFD system bandwidth.

This paper discusses recent advancements in smart connected biophysical signal sensing technology focusing on the development of wearable biosensors and the use of Electro-Quasistatic Human Body Communication and Edge-Analytics in the human state measurement systems for lower power consumption and physical layer security.

Liquid nitrogen impregnated PPLP and Kraft lapped papers are compared in terms of space charge distribution measurements for high voltage insulation in high power HVDC superconducting cables. Measurements with the pressure-wave-propagation method have shown that PPLP and Kraft paper samples behave similarly up to 30 kV/mm. No space charge has been observed in the insulation. Partial discharges at the interfaces of the carbon loaded paper electrodes are observed and produce an injection like phenomenon.

This paper is a case study outlining the successful Power System Study (PSS) of the electrical distribution system at a century-old paper mill. The electrical distribution system has been upgraded over the years with six in-house generators controlling the steam pressure and flow throughout the plant. Three generators operate at 13 800 Volts, and three generators operate at 2400 Volts. The self-generation makes up one half of the plant loading with the other half purchased from the local utility. This paper discusses the challenges involved in developing the computer model, and discusses the issues exposed during the analysis and how they were handled.

In this paper the experimental results of a compact low-power rectenna in paper substrate, designed to operate in the Wi-Fi band, are presented. The complete prototype, based on an annular slot antenna and a single-diode rectifier, features a weight of 1.5 grams and shows an RF-to-dc conversion efficiency in the design band of about 40 % for a -10 dBm available input power, of about 28 % at -15 dBm, and in the range [10, 22] % at -20 dBm, corresponding to an output DC voltage in the order of 320, 240 and 60 mV respectively. Additionally, the rectenna features an efficiency higher then 7 % in the whole band 1.8-2.7 dBm for a power density estimated around 3 μW/cm2.

The power density and total power from the package have been increased significantly. The rapid rate of power density increases from one generation to the next not only happens at the device level but also happens at the localized area on the devices. The objective of this study is to build more understanding of the localized high-power density in silicon blocks with respect to the impact in temperature gradient and reliability of the silicon. Conventionally, individual design block power usage numbers are often reported from circuit simulations without considering physical location of transistors and metal wires. However, in a silicon block design, certain transistors may consume significantly more power than others due to higher load capacitance, current draw, frequency, or toggle rate. Therefore, the power distribution is uneven within the design block even in the same use case. In order to gain a better understanding of power density peak spot inside of a single design block, in this study, the transistor activity is dynamically analyzed with circuit simulation vectors of an actual Versal product use case and the spatial power distribution of a 0.5mm x 0.5mm design block is reported in an granularity of 10um x 10um and turn x turn respectively. The analysis results show that the local heat flux can be several magnitudes higher when the design block is analyzed in more granularity. The local heat flux creates local hot spot that was overlooked. The max hotspot temperature would not be captured by the sensor because this specific hotspot sensor location would not be known at first hand due to uncertainty of the exact location created by the local hot spot. Understanding that there can be temperature sensors located some distance(700um) away from hotspot, reporting out the temperature, the device max temperature can be higher than the system monitor readout. Given this max temperature discrepancy, a correlation for max temperature based on heat flux density, source area, heat sink resistance, and senor location would be defined to estimate the max temperature. When the semiconductor chip has hot spots, it affects reliability of the chip. Most of reliability mechanisms result in shorter lifetime with higher temperature and temperature gradients. When a small portion of product has local temperature increase by whatever reason, long-term circuit performance should be altered due to enhanced or reduced aging effect. The device long term reliability is reassessed based on the new discovered localized hot spot.

This work presents an experimental study of second mode positive streamers propagating along mineral oilpaper interfaces. A point-plane arrangement immersed in mineral oil with the paper inclined 60 degrees to the plane electrode is used to create the liquid-solid interface. Kraft paper and a kraft fibril paper, made from cellulosic micro and nano fibrils, with higher density and lower surface roughness are used as the solid materials. High speed shadowgraphy and charge recordings are used to compare the propagation of second mode positive streamers along the mineral oil-kraft paper and mineral oil-kraft fibril paper. Streamers creeping along the mineral oil-kraft paper interface propagate mainly into the liquid, with one or two main filaments. In comparison, the streamers propagating along the kraft fibril paper show a strong reduction of the branching; these streamers consist of a single filament that propagates exactly on the solid surface. Streamers along the kraft fibril paper also have longer propagation time than for the case with kraft paper. Mutual electrostatic shielding between filaments is observed for the streamers creeping on the kraft paper. An electrostatic analysis of the influence of permittivity, density and surface roughness of the solid in the electrical properties of the streamer filaments is also performed.

An investigation has been made on Paper-based substrate integrated waveguide (SIW) antenna operating around 21 GHz. The proposed antenna is an SIW square cavity backed radiating rectangular slot. It has the advantage of ultra low profile which makes it suitable for high integration microwave circuits. In addition, this antenna is well shielded in order to be fabricated for application in emerging wireless communication systems. Moreover, a wide bandwidth of almost 3.5 GHz is achieved and a high gain equal to 1.82dB is noted which is not commonly performed for paper-based antenna.

Water inside a transformer tank is undesirable because this water causes the following problems. Firstly, on overload bubbles of water may form in the oil weakening its dielectric strength and increasing the risk of catastrophic flashovers across the oil. Secondly, it shortens the life expectancy of the Kraft paper insulation, which is one of the main factors limiting the functional life of transformers. It is therefore necessary to measure the water content of paper insulation so that a utility can take corrective action when required. Cellulose adsorption isotherms have been used to determine the water content of paper using online water activity probes. A disadvantage however is that the application of this method requires that the insulation media is in thermodynamic equilibrium, which due to load cycling usually is not the case. Practically, this problem is resolved by taking a long-term average of the measurements. This solution is not optimal because actual changes in water content will also be smoothed out. The migration of water between paper and oil is a very slow process. Therefore, a low-pass mathematical filter was developed which would retain this process but reject higher frequency components. This filter was also investigated using measurement from operating power transformers.

Smart devices are quickly becoming ubiquitous with the rise of portable biosensors and the internet of things. There exists particular interest in enhancing common objects to have smart capabilities and finding inexpensive solutions for diagnostic tools. One such example is transforming paper items into interactive devices and point-of-care analytic products. Due to the lightweight, flexible, and cost-efficient qualities of paper, unobtrusively powering these devices remains an outstanding problem. In this paper, we demonstrate an electrostatic human-touch powered energy harvesting system, integrated with flexible painted conductive electrodes on paper. This system harvests 8.5 nJ of energy and reaches a voltage of 1.3 V on a 10 nF energy storage capacitor. This technology not only provides a method of powering paper-based products with routine human gestures but can also detect human touch for input communication to sensors.

Demand of wearable, portable, lightweight, foldable and eco-friendly electronics is enlarged, and compatible energy storage systems is a prominent topic of research. Highly cost efficient and foldable energy storage systems should be mounted on wearable, foldable and portable electronics. Current fabrication techniques of typical electronic systems are complex and expensive. To address these requirements, paper based foldable and easy go designed supercapacitor-based energy storage devices are suggested and reported. Electrochemical supercapacitors (ESCs) could store charges without chemical reaction and have fast charging/discharging speed. We reported an electric three-layer capacitor fabricated using aluminum foil-based electrodes on baking papers. Low cost and solvent free bench top fabrication process includes direct deposition of aluminum foil using gum on baking paper is demonstrated. Four layers of aluminum foil are stacked on baking paper to achieve high energy storage capability. This aluminum foil based layered structure gives us high conductivity and reliable charging/discharging properties. This device exhibits an excellent cyclability (>5,000 cycles). Device having minor retention in performance under continuous dynamic operations of forceful bending at different angles. The design concept is based on folding-cutting-pasting procedure that provides us flexible production protocol to design and manufacture supercapacitors with adaptable electrical characteristics and configurations. Baking paper is biopolymer-based substrate and can store 0.72 mJ energy. The Electrochemical supercapacitors are based on aluminum foil electrodes on baking paper with gum, so there can realize foldable, eco-friendly, ultra-low cost and easy go designed energy sources for foldable, portable, flexible, wearable and green electronics in the future. Electrochemical supercapacitors could be able to store energy generated from small portable energy generators like triboelectric Nanogenerators for portable, flexible and wearable electronic systems.

IEEE 1584–2018 contains a significant update to industry models for predicting the incident energy from arc flash. These models include different box sizes, voltages, and electrode geometries. Predictions from these models are compared to tests on medium-voltage equipment. Equipment includes circuit-breaker cabinets, live-front switches, and live-front transformers. Results show what input assumptions are most applicable for each type of equipment (including vertical and horizontal electrodes). For some equipment, particularly with horizontal electrodes, the 1584–2018 predictions underpredicted measurements of incident energy, so multiplier factors may be needed.

Solid state circuit breakers recently entered the marketplace for certain low voltage applications. Solid state circuit breakers have the potential to provide circuit breaker operating improvements towards various applications, especially for electrical safety applications. These performance improvements are achieved by the solid state circuit breaker's switching speed in microseconds. During certain short circuit conditions, solid state circuit breakers are magnitudes faster than any other circuit breaker available in the marketplace. Their speed advantage is due to the solid state circuit breaker breaking the circuit path with a semiconductor switch. Circuit breakers are traditionally manufactured using mechanical parts to make or break a circuit, and they typically operate in the millisecond range. There are operational trade-offs to utilizing a solid state circuit breaker, for example heat generation through the semiconductor switch is greater than that of mechanical circuit breaker contacts. However, in certain applications, the benefits of using a solid state circuit breaker may outweigh the disadvantages making the solid state circuit breaker a viable option to consider.

OSHA §1910.269 Appendix E ‘Table 6’- Incident Heat Energy for Various Fault Currents, Clearing Times, and Voltages of 4.0 to 46kV: Rubber Insulating Glove Exposures Involving Phase-to-Ground Arcs in Open Air ONLY and ‘Table 7’- Incident Heat Energy for Various Fault Currents, Clearing Times, and Voltages: Live-line Tool Exposures involving Phase-to-Ground Arcs in Open Air ONLY and NESC-2012 Tables ‘410-2’ Clothing and Clothing Systems -voltage, fault current and maximum clearing time for voltages 1.1kV to 46kV and ‘410-3’ Live-line Tool Work Clothing and Clothing Systems - voltage, fault current and maximum clearing time for voltages 46.1kV to 800kV were developed using a commercially available computer program. However, the table values are only provided for a few discrete available fault current values. By reproducing the inputs and outputs using the same version of the commercially available software, values for more than those few discrete available fault currents can be produced. Equivalent power formulas can then be developed that will conservatively envelope all the incident energy values for a complete range of available fault currents for each given set of conditions. This provides simplification and ease of use for end users.

International audience; A configuration of antenna using flexible substrate for RF energy harvesting system working at GSM frequency 1800 MHz is presented. The suspended structure is used to surpass the high loss of the substrate. By taking advantage of the flexible properties, the process of miniaturization is achieved through folding the substrate into sections. The antenna prototypes were fabricated and measured. With the compact size of 0.36 λ × 0.33 λ × 0.03 λ, the measured gain is 5.3 dB, about 10 dB gain increase compared to conventional structure.

In early 2003, CPFL Energia, a Brazilian utility, was interested on evaluating the performance of natural ester filled transformers, especially regarding the highly increased overloading capability. As a field test, in association with the transformer manufacturer “Itaipu Transformadores”, they built two prototype transformers. Based on original overhead distribution line three phases transformers of 15kV/45kVA, after small adjustments in the windings and cooling system, keeping same core and tank, associated with the use of natural ester based dielectric liquid, and increasing the average winding temperature rise limit from 55°C to 85°C and a hotspot temperature rise limit of 100°C, the transformer nominal rating was shifted to 88kVA.

We developed a rewritable field programmable gate array (FPGA) using NanoBridge® that exploits atom switch technology. NanoBridge® is newly developed copper wiring technology with dynamic connection capability. Programmable circuitry with SpaceWire interface is realized without configuration memory cells for storing circuit connection information. It prevents single event effect caused by radiation and provides remarkably low power consumption. The first demonstration of the NanoBridge® FPGA on orbit by JAXA's program is planned in 2018.

The article presents 12.5 Gbit/s Physical Media Attachment (PMA) units, TX and RX, fabricated in 90 nm bulk CMOS process. The PMA are designed for use in SpaceFibre/GigaSpaceWire (SpaceWire-RUS) systems for the space radars. The units comprise SERDES and clock and data recovery (CDR). Supported set of data rates includes those of 1.25, 2.5, 6.25 and 12.5 Gbit/s, but intermediate rates are also available.

The low carrier mobility of (printed) semiconductors and high variations of the printed/flexible electronic elements are some of the most difficult challenges for the practical realization of complex printed/flexible electronic circuits. Although contemporary circuit designs accommodate some degree of process variations in conventional silicon processes largely by negative feedback, negative feedback is largely inapplicable in printed/flexible electronics. This is because the gain of the transistors is too low in electronic circuits to realize high open-loop gain, but also because negative feedback is inapplicable to digital circuits in the traditional sense. In this paper, we describe the co-design between the first three supply chains of Printed/Flexible Electronics – the co-design between our modified semiconductor, Fully-Additive Low-Temperature All-Air Low-Variation Printed/Flexible Electronics printing process and a process-variation-tolerant digital circuit design methodology. The first two co-design supply chains pertain to a low-cost screen-printing process while the last co-design chain pertains to the Quasi-Delay-Insensitive asynchronous-logic digital design methodology (vis-a-vis synchronous-logic) that is self-timed, hence virtually tolerant to any variations. We will also delineate our measurements on digital circuit based on codesign of the aforesaid supply chains, depicting the merits of our modified semiconductor, low-variation printing process, and the ensuing functional printed digital circuit.

With fast switching GaN any parasitic gate loop inductance degrades the switching performance and may lead to false turn-on as well as gate voltage overshoot. Two approaches to overcome these challenges in driving GaN transistors are discussed in this paper. In a discrete silicon based driver, the gate loop inductance is actively utilized for a resonant gate drive approach. In a second implementation, the gate loop inductance is reduced close to zero by GaN-on-Si monolithic integration of the power transistor and the driver on one die. It includes an integrated supply voltage regulator circuit that generates the gate drive voltage out of the high-voltage switching node. The results show fast and robust switching behavior with minimal ringing.

Electric conduction of oil impregnated paper under different temperatures and different DC electric fields has significant influences on the insulation structure design of converter transformer. This paper focuses on the influence of temperature and DC Electric Field on the electric Conduction of oil impregnated paper insulation, as well as conduction mechanism of oil impregnated paper through the high-field conduction experiments. It is concluded that a raise in temperature and DC electric field leads to the higher conductivity of the oil impregnated paper sample. The activation energy representing conduction barrier height was obtained. Moreover, the mechanism of electric conduction in oil impregnated paper was analyzed, which confirms the hopping conduction model instead of space charge limited current theory. Based on the upper statement, the parameters like the electronic hopping distance δ and the parameter j0 were obtained and we explored the conductivity s changing along with the electric field under different temperatures.

Transformer oil, insulating paper, high voltage direct current (HVDC) bushings and on-load tap changer (OLTC) are essential parts of converter transformers. When the power flow of the HVDC system is reversed or a sudden outrage occurs, the charge field will deform the dielectric internal electric field, thus easily leading to the occurrence of discharge or insulation damage. In this case, it is necessary to carry out the characterization of the oil-paper interface to avoid these consequences. This paper analyses the interface charge accumulation and dissipation characteristics of an oil-paper insulation system under DC and polarity reversal voltages. Induced electrification was used to charge the composite oil-paper insulation. The amplitude of DC and polarity reversal voltages applied in this paper was 4 kV, and paper with thicknesses of 0.08 and 0.13 mm was used. From the research on different layers and thicknesses of paper, with an increase in the number of the paper layers, the interface charge density decreases. Regarding the DC polarity reversal effect, increasing the thickness of the paper is equivalent to adding paper layers. The dissipation rate of the positive interface charge is quicker than that of the negative one. In the polarity reversal test, the dissipation rate becomes smaller as the reversal time gets longer.

Under the HVDC condition, the formation of the space charge in the oil paper system could affect the electric field distribution for converter transformers. Therefore, it is important to analyze the factors that determine the space charge behavior such as the temperature, moisture, electric field, oil paper thickness ratio and multilayers such as (Oil+Paper+Oil+Paper) structure. This paper focuses on the space charge distribution affected by the multilayers (O+P+O+P) oil paper structure and different oil paper thickness ratios. The pulsed electroacoustic method (PEA) was used to measure space charge distributions. It is found that increasing oil thickness could facilitate charge injection. However, the increase of pressboard thickness could prevent the charge injection. It is also found that the same oil paper thickness ratio could lead to similar space charge injection within the oil paper sample under the same 10 kV/mm electric field. Therefore, based on the same oil paper thickness ratio, space charge measured from the thinner thickness sample were further applied to the thicker thickness sample to estimate electric field distribution using COMSOL software, which cannot be measured by the PEA system directly.

This talk will review our recent work on a high-speed avalanche photodiode (APD). Recent results show 100-Gbit/s PAM4 40-km transmission with receiver sensitivity exceeding -14 dBm when the APD is combined with in-house SOA-integrated EML.

In order to assess the moisture content of insulating pressboard in oil-immersed transformer, and thus providing reliable guidance for insulation condition and life estimation of oil-immersed transformer, in this paper, we made four groups of oil-paper insulation samples with different moisture content under laboratory conditions and studied the relationship between pressboard and moisture content by using polarization and depolarization current (PDC) technique. The experiment result shows that PDC curve is very sensitive to the change of moisture content, and the change of moisture content mainly affects the tail of depolarization current curve; the extended Debye model parameters can be obtained from depolarization current curve, and as the moisture content increases the number of branches in Debye model increases, the largest time constant becomes large; the peak of time domain spectroscopy turn up at 1000s., the time constant branch which is longer than 1000s presents the pressboard branches of Debye model; the feature quantity Q paper can show the internal polarization of insulating paper and has a linear fitting relationship with moisture content, so Q paper can be used to assess the moisture content of insulating pressboard.

This paper presents the design of a novel rectenna based on a tapered annular slot and a single-diode rectifier, optimized to operate in the Wi-Fi band and in presence of low input power (Pavs=-15 dBm). In order to obtain a compact layout a double-layer architecture has been considered, according to which the interior metal surface of the annular slot is employed as ground plane for the rectifying circuit placed on the other side of the substrate. As a result, a rectenna with an active area of only 40 × 33 mm2 and an efficiency included between 26.5 and 28% has been obtained. The antenna has been fabricated in paper substrate and tested in the anechoic chamber. Then, the rectifier has been designed and optimized within the Advanced Design System suite. Finally, the rectenna performance has been discussed and compared to the State of the Art (SoA).

Dielectric response measurements are an important maintenance and diagnostic tool for large oil filled power transformers. Regardless of if the measurements being performed in the time domain or in the frequency domain, the developed tools rely on the dielectric response being linear with excitation voltage magnitude. This paper details work done in an initial investigation into the measurement of the non-linear dielectric response in oil-paper insulated power transformers using frequency domain measurements. Measurements were performed on two transformers, with non-linear response currents measured at the higher excitation voltage levels. It was found that non-linearity in the dielectric response will result in the generation of harmonics currents particularly 3rd and 5th harmonics. There will also be effects on the fundamental current magnitude due to the higher order dielectric susceptibilities. The higher order susceptibilities will thus be evident in the measured fundamental complex admittance of the dielectric.

This paper presents the design and implementation in paper substrate of a harmonic RFID chipless sensing tag. The proposed sensor is based on a Wheatstone bridge, where two of the four impedances change dynamically according to a physical parameter that has to be monitored. The passive tag is interrogated by a signal at f 0 = 1.04 GHz and the signal transmitted back to the reader at 2f 0 = 2.08 GHz is proportional to the magnitude of the parameter variation. A harmonic RFID experiment proves that this kind of architecture is capable of providing a dynamic range of more than 40 dB.

The vision of Internet of Things (IoT) has evolved the needs of providing seamless connectivity between devices across the globe. A potential solution to this requirement is to launch a CubeSat constellation that can provide broadband Internet access to rural and undeveloped areas (Internet of Space (IoS)). This has escalated the need for low-cost, low-profile antennas with wide angle beam steering capabilities. In this work, we elaborate on the design of a broadband, circularly polarized reflectarray capable of dynamic beam steering in the frequency range of 17.8-20.2 GHz. The reflectarray unit cell consists of a set of four copies of rotated Archimedean spiral arms, and the desired phase shift is obtained by suitably switching between these arms through PIN diodes. Representative prototypes have been fabricated and measured, and beam scans up to 60° have been achieved.

A number of power transformer failures occur due to the addition of DBDS compound in transformer oil. When DBDS reacts with Cu, it results in the breakdown of DBDS and thus pawing way to the formation of CU 2 S. The CU 2 S on the surface of the copper conductor migrates from one layer to another layer of insulation papers (Kraft papers) and this results in lowering of dielectric strength and thus electrical faults occur. The metal passivators such as Irgamet 39™, Benzotriazole (BTA-Aldrich) and 6Bis-(1-methyl-1-phenylethyl) Phenol (BMPEP-Aldrich) can be used to suppress the formation of copper sulfide. This addition of metal passivators to oil does not reduce or eliminate DBDS [1–6]. In this paper the effect of DBDS on DC Resistance of paper oil insulation system has been studied Experimental study has been carried out to describe the role of DBDS in fall of DC Resistance of paper-oil insulation of transformers. Different quantities of DBDS were added with pure transformer oil and the effect it will have on dc resistance under different applied voltages for different time intervals have been compared and contrasted.

This study represents a paper based energy generator from mixing waters with different salinity. Since the proposed device consists of wax patterned papers that can control microflow and a flexible cation exchange membrane (polycarbonate track-etched (PCTE)), the efficient pumpless reverse electrodialysis (RED) microplatform can be realized successfully. The presented system is flexible, portable and cost-effective, and moreover, shows that the power generation is possible, even in very high concentrated salinity, so it is very promising for practical application.

One of the most important parts of electric power equipment is the insulation system. Insulation system must be in a good condition for reliable and safe operation of electrical devices. During the lifetime of the electrical equipment, insulation system is exposed to various factors which could have negative influence on the properties of the insulation system. High temperature is one of the factors known to cause a degradation of the insulation system. Insulation system of transformers consists of two parts - liquid and solid. Liquid portion is represented by insulation oil and the solid one is represented by insulation paper. This paper focus on the investigation of how an accelerated ageing influences the properties of oil impregnated paper. Vegetable oil with its high flash point, high degradation rate and the reproducibility represents a potential new type of insulation oil which is expected to replace currently used mineral oils. Research of the vegetable oil properties is therefore a crucial step towards its future use. Properties such as relative permittivity, dissipation factor and the breakdown voltage will be described and analyzed.

Respiration is a key vital sign indicative of an individual's health. Current approaches of respiration sensing require direct contact with the body. Moreover, they are expensive and need bulky holter monitors for continuous realtime monitoring. In this study, we propose a low-cost capacitive sensor fabricated using screen printing of carbon paste interdigitated electrodes on paper substrate for respiration monitoring. Cellulosic paper provides a microporous network to trap exhaled breath. Respiration causes the dielectric constant of the paper to change, mostly as a function of breath humidity, which in turn changes the capacitance of the sensor. The interdigitated electrodes configuration is shown to provide better response time compared to resistive configuration. A simple phase sensitive detector-based circuit was used to convert the capacitance change into a measurable output voltage. The MSP430 microcontroller was used for data acquisition and voltage measurement. A graphical user interface was designed for real time respiration monitoring. Experimental results validate the performance of this sensor.

Performance of electrical energy storage system and life expectancy of components of storage system plays vital role in performance of electric vehicle. Based on desirable electrical characteristics compared to Li ion batteries, Supercapacitor Energy storage system (SCESS) is nowadays involved as basic element in energy storage system of electric vehicle. Among various factors that decide life expectancy of supercapacitors, major attention is gained by voltage imbalance during charging of array of supercapacitors. Various techniques of active voltage balancing are already introduced and implemented in practical applications. To overcome disadvantages and improve efficiency of these techniques, modifications are done in traditional balancing circuits and also new techniques are introduced by researchers in recent years. This paper reviews about recent active voltage balancing techniques for array of supercapacitor energy storage system for various applications.

This paper reviews key developments and the continuation of low power techniques needed from the Moore to AI eras. SRAM with a wider range of operation, from extreme low to high voltages, is enabled using novel circuit techniques and demonstrated for edge or data centric accelerators. These techniques exploit interconnect as well as inductor and capacitor coupling for boosting on demand. Several chips fabricated in 14nm SOI technology show functional 8T SRAM down to 0.24V–0.30V These new techniques can lead to lower voltage operation of cognitive and neural network for IoT and data centric applications.

Different methodologies have been embraced on reaping encompassing energy as economical, support free, and green power hotspots for driving some little gadgets because of the increased energy crisis. Triboelectric nanogenerators can harvest mechanical energy with effortlessness, cost-effectiveness, and robustness with the concept of electrostatic induction and triboelectric effect. A flexible TENG based on paper and PET has been fabricated of 4×1.8Inch2 which generated the 16V with the output power of 11.42µW at the load of 25MΩ, which can power up several Light Emitting Diodes LED’s and commercial capacitor rating of 4.7µF also charged with the TENG.

Integrated receivers with avalanche photodiodes (APDs) and single-photon avalanche diodes (SPADs) fabricated in 0.35μm CMOS and BiCMOS technologies are introduced. The APD receivers were used in error-free optical wireless communication (OWC) experiments with maximum transmission distances from 11m to 27m at 1Gb/s and from 6.5m to 16.5m at 2Gb/s without receiver lense and without optical filter. The APD receivers work up to and exceeding 2000lx ambient light. The newest trend are SPAD-based receivers, which reduce the gap to the quantum limit. The state of the art of SPAD receivers will be summarized and reviewed also in comparison to APD receivers.

The IBM Power Block is a high power density, low cost 48 V input DC-DC converter, designed to source up to 107 A of continuous output current to processors in high performance computing (HPC) and datacenter servers. Peak efficiency for a 0.75 V output is 90.6% at 45 A and 85.1% at 107 A. An active clamp forward converter (ACFC) architecture uses a pair of primary FETs and a pair of secondary FETs, separated by a planar transformer. A custom timing chip provides four gate timing signals, whose delays can be stored in internal fuses or set through a serial interface. Transformer and inductor magnetics are integrated into a single ferrite structure that allows induced electro motive forces (EMFs) to cancel, thereby providing near zero output current ripple at 0.75 V and low ripple 0.5 V to 1.0 V. Designed for 1 U servers, the Power Block has a 13 mm x 16 mm footprint and a 19 mm height. The electrical output contact’s flat top permits mounting a heat sink or cold plate.

Due to growing demand for higher data rates in wireless communication, high resolution requirement in radars, and emerging sensing applications, mm-wave frequency bands have become very attractive in recent years. Architectures and circuits of mm-wave transceivers are described and comparison of process technologies for mm-wave IC design is presented. Critical mm-wave circuit blocks and example implementations such as 60 GHz phased array, 28 GHz front-end, 79 GHz PMCW radar and 145 GHz FMCW radar are discussed and future trends are identified.

Fully depleted silicon-on-insulator (FD-SOI) semiconductor technology enables scalability of planar semiconductors devices with unique body-bias capability. FD-SOI technology offers best energy efficiency, highest performance of integrated RF and superior reliability ICs for IoT, automotive and mobile connectivity application.