Due to the high rise in luminous efficiency that high-brightness light-emitting diodes (HB-LEDs) have experienced recent years, many new applications been researched. This paper covers a streetlight LED application using offline integrated buck-flyback converter (IBFC) developed previous works. In this application, is used provide power-factor correction from universal ac source. A control loop LM3524 IC has implemented for testing feasibility of Enabling pulsewidth modulation dimming mode....

Due to the high rise in luminous efficiency that HB-LEDs have experienced last recent years, many new applications been researched. In this paper, a streetlight LED application will be covered, using integrated buck-flyback converter developed previous works, which performs power factor correction (PFC) from universal AC source, as well control loop LM3524 IC, allows PWM dimming operation mode. Firstly, load linearized and modeled order calculate IBFC topology properly. Afterwards,...

This paper deals with the capability of pulse width modulation (PWM) dimming operation added to high-power factor-integrated buck-flyback converter (IBFC), which was developed in previous works for LED lighting applications. First, two main techniques will be introduced, namely, analog and PWM dimming. Then, three schemes found literature, that is, enable dimming, series parallel briefly discussed. Afterwards, IBFC topology tested performing both In addition, a new proposal is introduced:...

Energy storage systems (ESSs) are gaining a lot of interest due to the trend increasing use renewable energies. This paper reviews different ESSs in power systems, especially microgrids showing their essential role enhancing performance electrical systems. Therefore, The classified into various technologies as function energy form and main relevant technical parameters. In this review paper, most common classifications presented, summarized, compared according characteristics. A specific...

Usually, pulsewidth modulation (PWM) operation is selected as the best dimming strategy to drive high-brightness LEDs. Nevertheless, obtain an enhanced full linear control of device, luminous flux should be measured. This paper proposes a method based on estimator emitted by LED. Based characterization LEDs, this defined. The provides value from only two temperature values (the case and ambient temperature). Once validated, electronic driver supply well digital scheme, are presented. Such...

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> In this paper, a novel single-stage electronic ballast with high power factor is presented. The circuit based on the integration of buck converter to provide correction, and flyback control lamp supply low-frequency square-waveform current. Both converters work in discontinuous conduction mode, which simplifies control. spite being an integrated topology, does not present additional stress...

This paper presents a new control method and detailed project methodology for the optimized connection of two converters, aiming to reduce redundant power processing, in order supply high-power light-emitting diodes (LEDs) with reduced capacitance high efficiency, directly from ac line. allows dealing major issues related LED driver: reduction efficiency increasing. The first converter provides factor correction, whereas second controls current through LED. basic idea consists making process...

The goal of this paper is the evaluation interleaved buck converter as a high-brightness (HB) LEDs electronic driver, comparing its performance with standard converter. main drawbacks come from high inductor value necessary to guarantee low output current ripple, which result in losses and rough switching waveforms at semiconductors. Additionally, when application demands pulsewidth modulation (PWM) dimming, inductance yields relatively dimming frequency that can audible noise problems due...

This paper presents a converter structure applied to supply high-power light-emitting diodes (LEDs) from the ac line in street lighting system, based on reduced redundant power processing principle. To guarantee high factor and low harmonic distortion for input current, buck-boost operating discontinuous conduction mode is employed as corrector. The second of controls current LED string, but it does not process all power. done by summing voltages first with converters. Avoiding double power,...

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> In this paper, a new control method for electronic ballasts based on the use of variable inductor is presented. The main goal to perform complete ballast by maintaining switching frequency constant and without using other parameters power converter, such as input voltage or duty cycle. magnetic regulator controlled means dc current, which allows performing both lamp soft starting dimming. Apart...

The use of supply frequencies above 50-60 Hz allows for an increase in the power density applied to ozonizer electrode surface and ozone production a given area, while decreasing necessary peak voltage. Parallel-resonant converters are well suited supplying high capacitive load ozonizers. Therefore, this paper current-fed parallel-resonant push-pull inverter is proposed as good option implement high-voltage high-frequency supplies generators. converter analyzed some important characteristics...

This paper addresses the estimation of grid impedance and control grid-tied converters by combining pulsed signal injection (PSI) observer-based techniques. A Luenberger-based observer is used for controlling grid-side current an LCL filter only measuring converter-side currents voltage. configuration mitigates effects parameter variation at filter. Under changes, will be triggering injection. PSI approach employed estimating online using a recursive least square algorithm. Compared with...

This article explores the use of a variable inductor as reactive element for energy transfer in dual-active-bridge (DAB) converter. By using controlled inductor, optimal switching region operation phase-shift DAB can be extended, and thus, high efficiencies achieved over wider load ranges compared to traditional solution. Moreover, combined inductance together with phase shift, two control parameters, allows linearization converter function, which improves stability performance controller....

Nowadays, Permanent Emergency Lighting Systems (PELSs) are widely used in many applications, including emergency exit indication and lighting critical or strategic points. Limitation operation hours classical lamps (10 000-20 000 h for fluorescent lamps) implies short lamp replacement times and, therefore, high maintenance costs. This paper shows an alternative solution based on high-efficiency LEDs. The long life (above 100 h) of LEDs with a very simple electronics circuitry interesting...

This paper deals with the thermal characteristics of <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">I</i> - xmlns:xlink="http://www.w3.org/1999/xlink">V</i> curve GaN-based white light-emitting diodes (LEDs), focused on variations dynamic resistance. The final goal this study is to improve static and operations LED driver within a wide range temperatures. Four LEDs from different manufacturers were chosen for study. first part shows...

This paper deals with the AC and DC dynamic voltage control in a hybrid DC/AC Microgrid (MG) central distributed Battery Energy Storage Systems (BESSs), applying power sharing mechanism between different devices MG.The MG is composed by multiport transformation center two fixed frequency 3 phase Nanogrids (NGs) coupled to bus through 3-phase Power Electronic Converters (PECs).The system pursues minimize dependence on utility grid stress MGs BESS, while increasing handling capability overall...

A low-cost high-frequency power supply for ozone generation is presented in this paper. The paper addresses two important issues. Firstly, the reactor tested at high frequency and a new model of type load proposed. Secondly, stage analyzed, obtaining some characteristics that allow correct design converter. Simulation experimental results are also provided to evaluate possibilities proposed

This paper presents a full ballast for driving an assembly of high brightness LEDs, based on new dc to converter. The converter provides constant current waveform the load parting from DC bus voltage. converter, operating with peak control, keeps through LEDs independently is carried out internally by self-adjusting switching frequency Thus, requirements capacitance capacitor are greatly diminished, allowing avoidance electrolytic technology. Also, low PWM dimming can be easily. present work...

This work presents a review of power-factor-correction (PFC) circuits for low- and medium-power single-phase power supplies. The main idea is not just to show the state art this topic but select most interesting topologies each application depending on level, input voltage range, output voltage. Since IEC 61000-3-2 regulations came into force, many new have been presented trying obtain cost-effective solution reduce current harmonic content. Each one them has its range due inherent...

In this paper, a study about acoustic resonance (AR) in low-wattage metal halide lamps is presented. The are supplied with typical low frequency square waveform on which high sinusoidal ripple superposed. goal to emulate the same waveforms generated by electronic ballast. way, ARs that appear lamp can be characterized against amplitude and frequency. Different lamp's manufacturers burning hours used. obtained results intended employed further reliable designs of low-frequency square-waveform...

This paper deals with the capability of dimming operation added to Integrated Buck-Flyback Converter (IBFC) topology developed in previous works. Firstly, three main methods that have been identified by authors such as enable dimming, shunt and series will be briefly commented. Afterwards, IBFC tested performing at 100 Hz 200 Hz. Secondly, besides methods, a new proposal is introduced: high frequency PWM which overcomes issues faced when developing constant-current fixed-frequency controlled...

In this paper the integrated double buck-boost (IDBB) converter operating with both stages in discontinuous conduction mode (DCM) is analyzed. The intended to supply high voltage LED lamps from mains, typically street lighting applications. A input power factor assured by first stage DCM, thus verifying harmonic injection standards. case, second also operated DCM as an option continuous (CCM) that has been studied a previous paper. behavior of compared operation CCM. It demonstrated...

In this paper, a novel topology to supply metal halide (MH) lamps using sinusoidal waveform with superposed third harmonic is proposed. By employing technique, the lamp supplied an approximated square waveform, but it reduces content and, therefore, electromagnetic interference and radio-frequency interference. The proposed analyzed designed for 35-W MH ceramic discharge tube. Experimental results prove that operation stable at operating frequencies where acoustic resonances were previously...

Improvements in power electronics are basically the result of research two main fields, namely: 1) new topologies and 2) devices. Researchers' efforts to achieve improved necessarily limited by characteristics As a result, both devices must move forward jointly at same time. This letter studies impact silicon carbide diodes on classic structure power-factor correction-the boost converter.