High frequency electronic ballast provides line frequency lamp current

Most electronic ballasts for fluorescent lamps provide a sinusoidal lamp current at the switching frequency. The high-frequency current flowing through the lamp can generate significant radiated noise, which is unacceptable in noise-sensitive applications, such as fluorescent lights in airplanes. Using shielded enclosures for the lamps may solve the problem, but it is expensive. A discontinuous conduction mode (DCM) electronic ballast topology is presented which drives the lamp with line frequency current, just like a magnetic ballast. However, compared to a magnetic ballast, its weight is substantially reduced due to operation at 40 kHz switching frequency. The topology also ensures unity power factor at the input and stable lamp operation at the output

Single-stage unity power factor based electronic ballast

This paper deals with the design, modeling, analysis and implementation of unity power factor (UPF) based electronic ballast for a fluorescent lamp (FL). The proposed electronic ballast uses a boost AC–DC converter as a power factor corrector (PFC) to improve the power quality at the input ac mains. In this single-stage UPF based electronic ballast, boost PFC converter and a half bridge series resonant inverter (HBSRI) share a common power switch. Thus one power switch is reduced as compared to the conventional two-stage approach. The design, modeling, analysis and implementation of this topology were carried out in MATLAB-Simulink environment for a T8 36 W, 220 V, 50 Hz fluorescent lamp. The switching frequency was kept more than the resonant frequency of the inverter, to ensure the zero voltage switching (ZVS) operation of both power switches. This resulted in reduction of high frequency switching losses. The power quality parameters such as displacement power factor (DPF), distortion factor (DF), power factor (PF), crest factor (CF) and total harmonic distortion of ac mains current (THDi) were evaluated to analyze the performance of proposed electronic ballast. Test results on a developed prototype of PFC electronic ballast were included to validate the design and simulated results

A Dimmable Resonant Inverter Electronic Ballast with Unity Power Factor

The conventional line-frequency magnetic ballast is heavy and bulky, which is too kept inside the compact fluorescent lamp (CFL). The paper describes about single stage dimmable electronic ballast with very high power factor and its high efficiency. A compact lamp power circuit is designed by using integrating a buck boost power factor corrector with a current-fed resonant inverter. Then the integration process gives a single power-processing unit that minimizes the number of circuit components. In this paper the proposed resonant inverter will reduces the circulating current in the resonant tank. It also allows simple gate drivers to be used so that isolation devices can be eliminated. The design, analysis and simulation were done using MATLAB SIMULINK. DOI: 10.17762/ijritcc2321-8169.150511

DESIGN OF ELECTRONIC BALLAST OF ONE BALLAST-TWO LAMP SYSTEM USING RAPID START TECHNIQUE

This project is about designing electronic ballast of one ballast–two lamp system using rapid start technique. Rapid start technique will start lamps quickly without flicker by heating the lamps electrodes and simultaneously applying the starting voltage. Rapid start technique is chosen because it provides a low starting voltage about 3.5 volts to the electrodes for one second before lamp ignition. The proposed circuit design consists of full bridge rectifier and boost converter, as a power factor correction (PFC) stage, integrate with a resonant half bridge inverter, used as lamp power control stage. Two lamps connection in parallel will be used as load to verify the objective. All the development of designing electronic ballast using one ballast–two lamp system with rapid start technique and the simulation will be through Multisim. This project is aim to design and improve the electronic ballast based on initial voltage and initial current. It is found that the current to the load is lower when two lamps are used

A review and classification of LED ballasts

This paper presents a review on existing ballasts for light-emitting diodes (LED) with considerations to their compliance to regulations, technological challenges, and on meeting various application requirements. All existing LED ballasts, including those proposed in recent literature, have been appropriately classified and systematically organized for the discussion. The dissemination of this information and its understanding is helpful for future R&D pursuits in this area. © 2013 IEEE.published_or_final_versio

Power Flow Analysis and Critical Design Issues of Retrofit Light-Emitting Diode (LED) Light Bulb

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The Sunrise Mission

The first science flight of the balloon-borne \Sunrise telescope took place in June 2009 from ESRANGE (near Kiruna/Sweden) to Somerset Island in northern Canada. We describe the scientific aims and mission concept of the project and give an overview and a description of the various hardware components: the 1-m main telescope with its postfocus science instruments (the UV filter imager SuFI and the imaging vector magnetograph IMaX) and support instruments (image stabilizing and light distribution system ISLiD and correlating wavefront sensor CWS), the optomechanical support structure and the instrument mounting concept, the gondola structure and the power, pointing, and telemetry systems, and the general electronics architecture. We also explain the optimization of the structural and thermal design of the complete payload. The preparations for the science flight are described, including AIV and ground calibration of the instruments. The course of events during the science flight is outlined, up to the recovery activities. Finally, the in-flight performance of the instrumentation is briefly summarized.Comment: 35 pages, 17 figure