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Although compact fluorescent lamps (CFLs) have been in the market for a long time, many of them do not achieve the same power factor as the incandescent lamps do, which appears to be a significant problem for the utility with the current widespread use of CFLs for household lightings. A single-stage single-switch electronic ballast with active power factor correction is presented in this study for CFL applications. Unlike other single-switch ballast circuits, the presented integrated dual-boost converter circuit can produce a symmetric bipolar square-wave voltage, thus generating a near-pure high-frequency sinusoidal voltage on the lamp, which is beneficial to the CFL lifetime. Moreover, its soft-switching variant can achieve the ZVZC turn-on and ZV turn-off for the MOSFET to improve the conversion efficiency. Detailed operating principles and circuit analysis of the proposed circuit have been provided in this study. Simulation and experimental results on a prototype of a 15 W CFL validate the theoretical analysis and highlight the merits of the presented work. [ABSTRACT FROM AUTHOR]

Although compact fluorescent lamps (CFLs) have been on the market for a long time, many of them do not achieve the same power factor as the incandescent lamps do, which presents a significant problem for the utility with the current widespread use of CFLs for household lightings. A simple single-switch electronic ballast with passive valley-fill power factor correction is proposed in this paper for CFL application. The proposed single-switch ballast circuit is able to achieve zero current switching to maximize the circuit efficiency. A simple feedback circuit with duty ratio control is also proposed to improve the high lamp current crest factor caused by the valley-fill circuit. Detailed descriptions and analysis of the circuit operating principles are provided in this paper. Simulation and experimental results are given on a 13-W CFL tube from Osram Sylvania to highlight the merits of the proposed work. [ABSTRACT FROM PUBLISHER]

A novel dimmable high-power-factor compact fluorescent lamp (CFL) electronic ballast that is compatible with standard incandescent lamp dimmers is proposed in this paper. In the proposed system, the dimming controller uses the phase angle of the dimmer as the input feedforward parameter for the duty ratio control of the switch in the power circuit. As a result, a wide range of light output can be achieved with a small range of phase angles of the phase-cut dimmer. The ballast power circuit is a single-switch single-stage resonant inverter, which is essentially a fusion of a SEPIC converter and a single-switch current-fed inverter. Detailed operating principles of the proposed system will be discussed in this paper. System stability analysis that includes the effects of the phase-cut dimmer is also provided. Experimental results are given for a 13-W CFL to demonstrate and highlight the merits of the proposed work. [ABSTRACT FROM AUTHOR]

A novel single-stage single-switch electronic ballast topology with a unity power factor is presented in this paper. The proposed circuit consists of an integrated buck–boost stage that operates in the discontinuous conduction mode to provide a high power factor and a single-switch current-fed resonant inverter to stabilize the lamp current. The proposed topology presents a low cost and compact electronic ballast design method. The detailed descriptions of the circuit's operating principles are provided in this paper. The design equations and mathematical analysis regarding the proposed circuit are discussed in this paper. The proposed ballast has been tested with an 18-W compact fluorescent lamp, and the experimental results confirmed that a very high power factor of 0.995 and an efficiency of 83.4% have been achieved. [ABSTRACT FROM PUBLISHER]