Electronic Power Supply Research Articles

A Self-Adaptive DC/DC Buck Converter Control Modulation Design

DC/DC converter is widely used in many electronic application power supplies. Usually, in the previously DC/DC converter control modulation, the duty cycle can be changed according the feedback signal in pulse width modulation (PWM) or the frequency be changed with a constant ON time or OFF time in pulse frequency modulation (PFM). A self-adaptive DC/DC converter control modulation is proposed in this paper. Based on the outputs of two uniform operational transconductance amplifiers which are influenced by the feedback voltage, both of the pulse ON time and pulse OFF time will be changed simultaneously. A self-adaptive frequency can be achieved in this control modulation. It can get a same output voltage ripple with a lower control frequency.

A High Temperature, High Power Density Package for SiC and GaN Power Devices

In this work, a compact 600 – 1700 V high current power package housing either silicon carbide (SiC) or gallium nitride (GaN) power die was designed and developed. Several notable configurations of the package include diode half-bridges, co-packed MOSFET-diode pairs, and cascode configured GaN devices. In order to avoid a significant redesign effort for each new application or improvement in device technology, a device-neutral design strategy enables the use of a variety of die types from any manufacturer depending on the end-use application's requirements. The basic SOT-227 is a widely used package type found in everything from electronic welders and power supplies to motor controls and inverters. This module is a variant of that style of package which also addresses some issues that a standard SOT-227 package has when used in higher voltage applications; it has increased creepage and clearance distances which meet IPC, UL, and IEC standards up to 1700 volts while retaining an isolated substrate. It also has low parasitic values in comparison to the SOT-227. One of the key elements of this design is the removal of the baseplate. This allows for far lower weight, volume, and cost as well as reduced manufacturing complexity. The wide bandgap power package is composed of high temperature capable materials, which allow for the high junction temperatures inherent in these high power density devices. This paves the way for the design of a small, low-profile package with low parasitic inductances and a small junction-to-case thermal resistance. This paper will discuss the mechanical design of the power package as well as the three-dimensional finite-element modeling and analysis of the thermal, electrical, and mechanical characteristics. In addition, the electrical characteristics as a function of temperature of the power module up to 225 °C will be presented.

Алгоритм синтеза линейных антенных решеток c требуемой диаграммой направленности и целочисленными ампли­тудными коэффициентами

Ahe problem of technical implementation of phased array antennas (PAR) with the required radiation pattern (RP) is the complexity of the construction of the beamforming device that consists of a set of controlled attenuators and phase shifters. It is possible to simplify the technical implementation of PAR, if complex representation of coefficients of amplitude-phase distribution of the field along the lattice is approximated by real values in the synthesis stage. It is known that the amplitude distribution of the field in the aperture of the antenna array and the radiation pattern are associated with Fourier transform. Thus, the amplitude and phase coefficients are first calculated using the Fourier transform, and then processed according to the selected type of circuit realization of attenuators and phase shifters. The calculation of the inverse Fourier transform of the modified coefficients allows calculating the synthesized orientation function. This study aims to develop a search algorithm for amplitude and phase coefficients, taking into account the fact that integer-valued amplitudes and phases are technically easier to implement than real ones. Synthesis algorithm for equidistant linear array with a half-wavelength irradiators pitch (&l;/2) is as follows. From a given directivity function the discrete Fourier transform (DFT) in the form of an array of complex numbers is found, the resulting array is then transformed into a set of attenuations for attenuators and phase shifts for phase shifters, while the amplitude coefficients are rounded off to integers, and phases are binarizated (0, ?). The practical value of this algorithm is particularly high when using controlled phase shifters and attenuators integrally. The work confirms the possibility of a thermoelectric converter of human body application for an electronic medical thermometer power supply.

Enhancing Output Power of Cylindrical Triboelectric Nanogenerators by Segmentation Design and Multilayer Integration

The triboelectric nanogenerator (TENG) is a newly invented technology that is effective for harvesting ambient mechanical energy for portable electronics, self‐powered sensor networks, etc. Here, by introducing segmentation and multilayer integration into the cylindrical TENG, the generator's output is enhanced significantly. With a four‐layer and thirty‐segment configuration, the TENG produces a short‐circuit current of 86 μA (13.5 μA m−2) and power of 4.3 mW (676 mW m−2) at a rotating speed of 600 rpm, which are respectively over 70 and 15 times higher than those of the one‐layer and one‐segment structure. This makes the TENG a sufficient power supply for conventional electronics, such as light bulbs and temperature sensors. Furthermore, it is demonstrated that the segmentation design is a perfect self‐power management technique to automatically lower the TENG's output voltage and increase its output current without scarifying the output power. The fractal geometry is an effective way to maximize the TENG's contact surface area and thereby the output performance.

A Distributed DC Power Devise Based on DSP

The adjustable high-power distributed DC power supply controlled by DSP presented in this article is a new type of electronic power supply. Considering the features of modern power system, this article discusses and compares the principles of technical design and application of the adjustable high-power distributed DC power supply controlled by DSP with those of traditional DC power supply. The result suggests that the adjustable high-power distributed DC power supply controlled by DSP is easy to install, energy-saving and environment-friendly. It also has the characteristics of lower cost and higher performance.

Study on the influence of output inductance on DBD plasma uniformity

Abstract The presented work gives an overview on simulation and experimental results of the power supply parameters’ influence on DBD discharge uniformity. The proposed study is about the use of quasi-pulsed, power electronic power supply and a saturable inductor in series with the discharge cell [1]. The simulation results are presented with a parallel DBD reactor model with linear critical voltage distribution. A more uniform current waveform is observed, however, due to small reactor capacitances no streamer formation could be verified in calculations. An experimental test stand was prepared with a double dielectric barrier discharge arrangement. The experimental results are presented with regard to the electrical oscilloscope waveforms and ICCD camera imaging. A more homogenous plasma was observed in the case of saturable inductor with saturation current set at the point of discharge formation. Two possible mechanisms are connected with this phenomenon - inductive element current support during discharge and/or current rise-time limitation [1].

Analysis of transient state in HTS tapes under ripple DC load current

The paper concerns the analysis of transient state (quench transition) in HTS tapes loaded with the current having DC component together with a ripple component. Two shapes of the ripple were taken into account: sinusoidal and triangular. Very often HTS tape connected to a power electronic current supply (i.e. superconducting coil for SMES) that delivers DC current with ripples and it needs to be examined under such conditions. Additionally, measurements of electrical (and thermal) parameters under such ripple excitation is useful to tape characterization in broad range of load currents. The results presented in the paper were obtained using test bench which contains programmable DC supply and National Instruments data acquisition system. Voltage drops and load currents were measured vs. time. Analysis of measured parameters as a function of the current was used to tape description with quench dynamics taken into account. Results of measurements were also used to comparison with the results of numerical modelling based on FEM. Presented provisional results show possibility to use results of measurements in transient state to prepare inverse models of superconductors and their detailed numerical modelling.

Термоэлектрический источник питания для электронного медицинского термометра

At present chemical sources of electricity are used as power supplies for low-powered electronic equipment. Despite continuous quality improvement (CQI) of chemical sources of electricity they still have some critical faults, such as: relatively high specific overall dimensions, presence of self-discharge, short life and limited shelf life under low temperature storage. Moreover, the chemical source of electricity production is power-consuming, costly and environmentally harmful. The plurality of facts given above stipulates the search for new sources of electric energy eliminating the faults chemical ones possess. Therefore, thermoelectric power supply sources are especially prospective in this respect as thermoelectric generators in general have a long operational life, they are reliable for use in extreme conditions and do not need being changed periodically. It is a well-known fact that thermoelectric converter efficiency depends on the load resistance and the converter resistance matching, which are stipulated by such converter design. The results of calculations of a thermoelectric converter for a medical thermometer power supply are presented in this paper. The authors define a rational design of such a converter which is limited by technological complexity of small-size legs fabrication, on the one hand, and with the converter overall dimensions, on the other hand. The study carried out has shown the expediency of a thermoelectric converter application for various operational modes to provide an electronic medical thermometer power supply, particularly in the unmatched load mode with the converter efficiency dropping down five to tenfold. The work confirms the possibility of a thermoelectric converter of human body application for an electronic medical thermometer power supply.

Harmonics Mitigation Under Various Loading Conditions of PWM Current Controlled APF Using Fuzzy Logic Controller

The production of electric energy is basic pillar for normal functioning of every modern society. But in present day’s power distribution system is suffering from severe power quality problems. To reduce such problems we are using advanced technologies in power electronic devices (semi conductor devices). However these power equipments which include Adjustable Speed motor Drives (ASDs), electronic power supplies, direct current (DC) motor drives, battery chargers, electronic ballasts are responsible for the rise in related PQ problems. These non-linear loads are constructed by nonlinear devices. But these non-linear loads appear to be prime sources of harmonic distortion in power distribution system. Harmonic currents produced by non-linear loads are injected back into power distribution systems through the Point of Common Coupling (PCC). These harmonic currents can interact adversely with a wide range of power system equipment, most notably capacitors, transformers and motors causing additional losses, overheating and overloading. And also it can decrease the power quality in power distribution system. Traditionally, current harmonics caused by non-linear loads have been dealt with using passive filters consisting of capacitors, inductors and damping resistors. This paper mainly concentrates on proposing a new PWM current controlled Shunt Active Power Filter, to propose a simple current reference estimation method for the proposed topology, to design a Takagi-Sugeno (TS) type Fuzzy Logic Controller (FLC) to a three phase Shunt Active Power Filter which can decrease the harmonics so that the quality of power increases in power distribution systems. The first objective is achieved by designing a PWM current controlled Voltage Source Inverter which acts as a Shunt Active Filter for a three phase three wire system. For the second objective, this paper proposes the application of the extension instantaneous reactive-power (p-q) theorem to estimate the compensation current reference. The third objective is achieved by designing a Takagi-Sugeno (TS) Fuzzy Logic Controller with seven fuzzy sets for each input and output, triangular membership functions for simplicity, fuzzification using continuous universe of discourse and defuzzification using the centroid method. This paper will give the MATLAB/SIMULINK circuits of above proposals which interm gives the solutions to improve the power quality in power distribution systems.

Dimming control by variation of the switching frequency for high-intensity discharge lamps

In this paper, a high-frequency dimmable electronic power supply for the high-pressure sodium lamp is presented. The method includes a full bridge rectifier generating a dc-link voltage and a half bridge inverter to generate a frequency swept lamp power signal to drive the lamp while avoiding acoustic resonance. A dimming technique for a resonant circuit electronic ballast based on a variable frequency is introduced. In addition, the ability in the dimming range is demonstrated by experiments and simulation in order to verify the performance of the proposed circuit. A dimming range from 100% to 50% has been achieved. The efficiency is always higher than 89% and the ballast can accurately follow a fixed dimming plan.

Superconducting coil fed by PEM fuel cell

Fuel cells are electrochemical energy converters which allow transformation of the chemical energy of a fuel to electricity through oxido-reduction reaction. The voltage of an elementary cell is usually near 1 V in open circuit and around 0.6 V in nominal conditions of power generation. Fuel cells are then by essence low voltage sources, so that for most practical applications, power management is carried out by electronic converters, allowing in particular to rise the voltage to usual application levels.In this paper, we propose to take advantage of this low voltage for a specific application stack such as superconducting coils power supply. At present, such applications are dealt with the use of specific electronic power supplies, exhibiting in most cases a huge volume and/or a low energy yield.

Flexible Solid-State Supercapacitors Based on Three-Dimensional Graphene Hydrogel Films

Flexible solid-state supercapacitors are of considerable interest as mobile power supply for future flexible electronics. Graphene or carbon nanotubes based thin films have been used to fabricate flexible solid-state supercapacitors with high gravimetric specific capacitances (80-200 F/g), but usually with a rather low overall or areal specific capacitance (3-50 mF/cm(2)) due to the ultrasmall electrode thickness (typically a few micrometers) and ultralow mass loading, which is not desirable for practical applications. Here we report the exploration of a three-dimensional (3D) graphene hydrogel for the fabrication of high-performance solid-state flexible supercapacitors. With a highly interconnected 3D network structure, graphene hydrogel exhibits exceptional electrical conductivity and mechanical robustness to make it an excellent material for flexible energy storage devices. Our studies demonstrate that flexible supercapacitors with a 120 μm thick graphene hydrogel thin film can exhibit excellent capacitive characteristics, including a high gravimetric specific capacitance of 186 F/g (up to 196 F/g for a 42 μm thick electrode), an unprecedented areal specific capacitance of 372 mF/cm(2) (up to 402 mF/cm(2) for a 185 μm thick electrode), low leakage current (10.6 μA), excellent cycling stability, and extraordinary mechanical flexibility. This study demonstrates the exciting potential of 3D graphene macrostructures for high-performance flexible energy storage devices.

Design of a new switching power supply for the ATLAS TileCAL front-end electronics

We present the design of an upgraded switching power supply for the front-end electronics of the ATLAS hadron tile calorimeter (TileCAL) at the LHC. The new design features significant improvement in noise, improved fault detection, and improved reliability, while retaining the compact size, water-cooling, output control, and monitoring features. We discuss the steps taken to improve the design. We present the results from extensive radiation testing to qualify the design, including sensitivity to Single Event Upset. We also present our reliability analysis. Production of 2400 new bricks for the detector is currently in progress, and we present preliminary results from the production checkout.

Resonant inverter with resonance frequency tracking for DBD plasma reactor supply

This document gives an overview of a power supply construction suitable for dielectric barrier discharge (DBD) reactor excitation. The influence of temperature and voltage change on DBD reactor parameters is discussed. A power electronic supply system topology allowing for continuous resonant frequency tracking is proposed together with simulation and test stand results of operation. An additional feature of proposed topology is the output peak to peak voltage control.

Fabrication and tests of a three-dimensional microsupercapacitor using SU-8 photoresist as the separator

Presented is a microsupercapacitor using SU-8 photoresist as the separator, featuring by high-aspect-ratio three-dimensional (3D) electrodes and high capacity per unit area. A scalable and mechanically stable structure for microsupercapacitors has been designed. By combining the preparation strategy for self-supporting nanoporous electrodes with micromachining technologies for high-aspect-ratio structures, 3D electrodes that allow for a heavy load of electrode material per unit area has been achieved. Electrochemical characterisation results of the prototype using ionic liquid as the electrolyte demonstrate that the microsupercapacitor exhibits a high specific energy of 330 mJcm−2 and a large specific capacitance of 160 mFcm−2, which are attributed to both the high-performance materials and the well-designed microstructure. This device can be potentially applied to various energy systems, such as electronic backup power supplies and microenergy storage devices.

Aspectos metalúrgicos de revestimentos dissimilares com a superliga à base de níquel inconel 625

Prolongar a vida útil e aumentar a confiabilidade de equipamentos e tubulações de plantas de produção e processamento de petróleo é uma busca constante no setor de petróleo e gás. Tais aspectos dependem essencialmente do uso de ligas resistentes à corrosão. Neste contexto, a soldagem de revestimento com superligas à base de níquel tem sido uma alternativa interessante, pois confere aos equipamentos uma alta resistência à corrosão com um custo inferior, se comparado à fabricação de componentes ou tubulações maciças com superligas. Assim, o objetivo do presente trabalho foi investigar o comportamento metalúrgico de revestimento de superliga à base de níquel do tipo Inconel 625 depositados pelo processo TIG com alimentação de arame frio. As soldagens foram realizadas em uma bancada robotizada, empregando uma fonte eletrônica de soldagem com sistema de aquisição de dados para o monitoramento dos sinais de corrente e tensão. A caracterização microestrutural foi realizada através das técnicas de microscopia eletrônica de varredura (MEV) e transmissão (MET), espectroscopia de energia dispersiva de raios-X (EDS). Os resultados mostraram que a microestrutura do metal de solda foi constituída por uma matriz γ com fases secundárias ricas em Nb. Foi encontrada a formação de precipitados complexos de carbonetos/nitretos de Ti e Nb.

Experimental tests and reliability assessment of electronic ballast system

The necessity of clean energy resources development has increasingly become the focus of attention of the world. An important contribution to this topic could be given by minor waste in the illumination system. This paper presents results obtained by qualification tests implemented on electronic ballasts, with particular attention to on/off, thermal tests and EMC tests. Being the device under test an innovative electronic power supply system designed for application in energy saving, it is fundamental also an evaluation and analysis of the reliability performances. To this aim some results obtained with reliability prediction method are also presented in the paper.

Design and Development of Vibration Method for Vehicle Reverse System (VRS)

This paper discussed on design and development of Vehicle Reverse System (VRS) by using normal beeping car warning system and combination with vibrators in order to support the hearing impaired. This electronic device is an innovation product to support and help those hearing problem people such as elder person and disability person to have their own confident in driving their vehicles especially for detecting distance and location of the obstacle during reverse condition. This project is about developing of car warning system by using a vibrator as a warning device via main processing unit which consists of peripheral integrated circuit (PIC) and other electronic power supply which is received input signals from the distance sensor and translated it into the vibration composition when detecting obstacle. The vibration motor is a best solution to warn the hearing disability person because it uses touch sense of human when the system is run. In this system, there are four pieces of vibration motor are mounted to the driver's seat at different locations. Each location will have its own function that show different direction such as upper left, upper right, bottom left and bottom right. In this project, the effectiveness of the system gives command the direction of obstacle existence is very important and have been confirmed through simulation and experiment.

Design, Realization and Measurements of a Miniature Antenna for Implantable Wireless Communication Systems

The design procedure, realization and measurements of an implantable radiator for telemetry applications are presented. First, free space analysis allows the choice of the antenna typology with reduced computation time. Subsequently the antenna, inserted in a body phantom, is designed to take into account all the necessary electronic components, power supply and bio-compatible insulation so as to realize a complete implantable device. The conformal design has suitable dimensions for subcutaneous implantation (10 × 32.1 mm). The effect of different body phantoms is discussed. The radiator works in both the Medical Device Radiocommunication Service (MedRadio, 401-406 MHz) and the Industrial, Scientific and Medical (ISM, 2.4-2.5 GHz) bands. Simulated maximum gains attain -28.8 and - 18.5 dBi in the two desired frequency ranges, respectively, when the radiator is implanted subcutaneously in a homogenous cylindrical body phantom (80 × 110 mm) with muscle equivalent dielectric properties. Three antennas are realized and characterized in order to improve simulation calibration, electromagnetic performance, and to validate the repeatability of the manufacturing process. Measurements are also presented and a good correspondence with theoretical predictions is registered.

Market and patent analysis of commercializing biohydrogen technology

In the face of world-wide energy price fluctuation, energy supply security, and the energy crisis, it becomes an urgent issue to search for alternative methods for energy generation and to close the gap between the supply and demand of global energy. The current method of energy supply in Taiwan is through a centralized electronic power system, which is generated by a few large electronic power plants. Hydrogen fuel cell (HFC) has a characteristic of de-centralized electronic power supply system, which provides electronic power more reliably, efficiently and economically. Based on the output of Taiwan’s sewage, sludge, kitchen waste and biohydrogen technology, the preliminary market for biohydrogen fuel cell (BHFC) is positioning itself toward the supply of public electronic power within the housing communities. Based on the patent analysis of BHFC, this study finds that Taiwan pays more attention to the front-end manufacturing of raw materials and emphasizes the development of biohydrogen technology, while America and Japan mainly pay more attentions to rear-end product application and emphasize the application of hydrogen and fuel cells by integrating industrial opinions. Based on the market analysis of BHFC, this study finds that the product attributes, consumers’ characteristics and external variables strongly influence consumer’s purchase intention of biohydrogen technology products.