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,...

In this paper, a new technique for controlling dc-dc resonant converters is investigated. A variable inductance used to control and regulate the dc output voltage maintaining constant switching frequency half-bridge transistors. The characteristics of series parallel under proposed magnetic are obtained analyzed. order evaluate technique, laboratory prototype 48 V-input 5 V/10 A-output 500 kHz converter presented. methodology obtaining dynamic response using step test carried out. From...

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...

The steady state operation modes and the commutation zones of a single stage, high power factor ballast are studied. design criteria to allow operate at optimum soft switching conditions given. A control circuit is also proposed. High efficiency achieved by switching. Experimental results verify theoretical study.

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...

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...

In this paper a new technique to reduce the LED current ripple and storage capacitance in high power factor (PF) off-line supplies is investigated. The proposed methodology based on use of integrated converters (IPC) implement supply. Thus, first stage operates discontinuous conduction mode (DCM) provide PF. second can be operated either continuous (CCM) or DCM. A family IPCs used as lamp supplies. generalized analysis carried out order obtain important design equations conditions. Finally,...

A novel single-stage high-power-factor electronic ballast is presented in this paper. The obtained from the integration of a buck-boost converter and half-bridge LC resonant inverter. features lamp power regulation against line voltage fluctuations together with high factor dimming capability. steady-state analysis performed low-frequency model input stage derived. design example, including closed-loop circuitry, also presented. Finally some experimental results lab prototype are shown.

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...

In this paper, a study on LED retrofit solutions for low-voltage halogen cycle lamps is conducted. the first part of lamp based array designed to operate in substitution 12-V/50-W lamp, lighting fixtures which these are supplied using line transformer. The design includes selection an adequate terms lumen output and color temperature calculation necessary heatsink assure correct operation within selected range. second passive converter bridge rectifier limiting resistance studied tested...

A new single-stage high-power-factor electronic ballast based on a flyback power converter is presented in this paper. The able to supply fluorescent lamp, assuring high input factor for the utility line. Other features are lamp regulation against line voltage variations and low current crest factor, both long life. analyzed at steady-state operation design equations characteristics obtained. Also, procedure presented. Finally, simulation experimental results from laboratory prototype shown.

Abstract This paper deals with high frequency modeling of silent discharge ozone generators (OGs). The electrical characteristics two simple OGs operated at low and are analyzed compared. An equivalent electric model is proposed for the operation OG frequency. can be used to optimize electronic power converter supply Experimental results measured in laboratory particular presented validate model. Keywords: OzoneOzone GenerationSilent DischargeHigh-Frequency Ozone GeneratorsHigh-Frequency Model

In this paper a long-life high-power-factor integrated converter able to supply LED lamps in high-pressure-sodium (HPS) lamp retrofit applications is presented. The made up by the integration of buck-boost with buck converter, which provides necessary high input power factor and low voltage transformation ratio low-voltage array from mains. analysis carried out design procedure proposed. Also, performed so that capacitances are needed at output each semistage. This allows for use film...

A complete study of the clamped-mode (CM) series-parallel (LCC) resonant inverter together with some control-to-output characteristics are presented in this paper. Also, a new control method for CM LCC is introduced. With method, forced to operate optimum commutations and without handling reactive energy, thus minimizing both switching conduction losses. The corresponding design procedure illustrated example. Finally, experimental results obtained from prototype at laboratory also shown...

A novel single-stage high-power-factor electronic ballast obtained from the integration of a buck DC-to-DC converter and half-bridge resonant inverter is analyzed in this paper. The operated discontinuous conduction mode at constant frequency providing an input power factor high enough to satisfy present standard requirements. operation proposed also investigated detail paper, obtaining important equations characteristics order allow interested readers perform easy design. prototype...

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The use of high-efficiency LEDs in low-power lighting applications is growing continuously due to new advances LED features. lifetime a fluorescent lamp around 5000 h. This implies short lamp-replacement times and high maintenance costs. reduces drastically the costs long (<formula formulatype="inline"><tex Notation="TeX">${≫}\hbox{50}$</tex></formula> 000 h). One where using very interesting...

The first LED diode was created in 1969. Since then, they have been experiencing a continuous improvement luminous efficiency and power dissipation, achieving current AIInGaP InGaN devices for yellow to red, blue green, including white, colours respectively. experienced both dissipation makes them interesting lighting application automotive industry, where the advantages offered are numerous, from lower time response brake lights an operating life much higher than that of vehicle itself [1],...

A new single-stage high-power-factor electronic ballast based on a flyback converter is presented in this paper. The able to supply fluorescent lamp assuring high-input power factor for the utility line. Other features are regulation against line voltage variations and low current crest factor, both long life. analyzed at steady-state operation, design equations characteristics obtained. Also, procedure presented. Finally, simulation experimental results from laboratory prototype shown.

In this paper, a new distributive control system for indoor fluorescent lighting based on LonWorks technology is presented. The features the following elements: microprocessor-controlled lamp electronic ballast, communication using power line as media, and software Windows 95 environment. ballast has been especially designed to be operated under proposed system. Thus, it high-input factor, high-frequency supply, regulation against voltage variations, dimming capability, failure detection....

The design of dimming electronic ballasts for fluorescent lamps has to be made taking into account that lamp life is greatly affected by the starting scenario and how filament heating current varied during operation. Another important aspect ballast should provide a wide stable control range output power, some applications require down power less than 20% nominal value. One most commonly used topologies driving resonant half bridge inverter. In this topology, depends on both parameter...

Nowadays, permanent emergency lighting systems (PELS) are widely used in many applications: exit indication, critical or strategic points. Limitation operation hours classical lamps (10.000-20.000 for fluorescent lamps) implies short lamp replacement times and, therefore, high maintenance costs. This paper shows a driver based on flyback circuit PELS system. Control current mode assure constant LED's any battery condition. The long life (above 100.000 hours) of efficiency with very simple...

Discharge lamps present a negative dynamic characteristic that makes necessary using current limiting element. In high frequency resonant ballasts limitation is performed by the output tank, but in low-frequency square-wave electronic arc stabilization accomplished stage feeding square wave inverter. Therefore, design of input converter must be made taking into account lamp characteristic. This paper presents new procedure for obtaining small-signal metal halide proposed. Using proposed...

High intensity discharge (HID) lamps are the most suitable when both high light power levels and good color rendering researched. Some remarkable theoretical advantages would be obtained if these kinds of were driven with frequency (HF) electronic ballasts. Nevertheless, at frequencies, acoustic resonances (AR) phenomenon appears. Low wattage metal halide (MH) are, among all HID lamps, affected by this phenomenon. To obtain lack AR in lamp harmonics must have a lower amplitude than certain...

This paper proposes an electronic driver for public lighting systems. The input stage is based on the integration of two flyback converters with different polarities, in order to avoid use diode bridge rectifying stage. output a boost converter current control. proposed circuit introduced and analyzed, design example 50-W light-emitting lamp presented. most relevant simulation experimental results are also shown, validate idea. A comparison terms efficiency carried out between topology...