A Novel Single-switch High Power Factor Led Driver Topology With High-frequency Pwm Dimming Capability

In this work, a novel off-line converter with power factor correction (PFC) and pulse-width modulated (PWM) dimming function employing a single active power switch is proposed for LED lighting. The proposed converter is a slightly modified flyback topology which enables the main switch to be used bo...

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Detalhes bibliográficos
Autores: Almeida, Pedro S., Soares, Guilherme M., Braga, Henrique A. C.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2013
País:Brasil
Recursos:Associação Brasileira de Eletrônica de Potência (SOBRAEP)
Repositorio:Eletrônica de Potência (Online)
Idioma:inglés
OAI Identifier:oai:ojs2.journal.sobraep.org.br:article/389
Acesso em linha:https://journal.sobraep.org.br/index.php/rep/article/view/389
Access Level:acceso abierto
Palavra-chave:LED Dimming
Off-line LED Drivers
Power Factor Correction
Single-switch LED Driver
Descrição
Resumo:In this work, a novel off-line converter with power factor correction (PFC) and pulse-width modulated (PWM) dimming function employing a single active power switch is proposed for LED lighting. The proposed converter is a slightly modified flyback topology which enables the main switch to be used both for power factor correction and PWM high-frequency dimming with a constant peak on the current through the LEDs, thus conserving chromatic characteristics of emitted light. The proposed control scheme uses duty-cycle to control the light level, while switching frequency is varied along to adjust the input power and keep a constant LED peak current. The converter is able to dim LEDs without losing its PFC characteristics. Mathematical description and experimental results of a prototype with 100 W of peak power fed from 127 V mains voltage are presented in this paper to show feasibility of the novel single-switch driver proposal.