HIGH POWER FACTOR ELECTRONIC LIGHTING SYSTEM EMPLOYING THE SEPIC AND HALF-BRIDGE INVERTER FOR AC POWER LEDS
Luiz Haruki Okida1; Claudinor Bitencourt Nascimento1
1 Federal University of Technology of Parana (UTFPR)
Baixar PDF doi:10.20906/CPS/CBA2018-1190
Resumo
The use of LEDs that operate in alternating current (ac) can be considered with a good solution for lighting system ap-plications. With high direct breakdown voltage and low driving current, through a resistor element, the AC power LEDs can be directly connected to the power supply. However, the direct connection in the power supply produces a high harmonic distortion in input current and the IEC 61.000-3-2 is not attended. This paper presents an electronic lighting system with power factor correction (PFC) to drive AC power LEDs employing the SEPIC converter associated to the Half-Bridge voltage inverter. SEPIC converter carries out the power factor correction and DC bus voltage regulation. Half-Bridge inverter operating with asymmetrical PWM gate pulses, i.e., using I-LFSQW (Low Frequency Square Wave Current) technique, carries out the reversal of voltage and current in the load. Simulation results for two conduction modes (DCM-Discontinuous Conduction Mode and BCM-Boundary Conduction Mode) and experimental results for DCM will be presented.
Palavras-chave: AC Power LEDs; SEPIC converter; Half-Bridge inverter; Power Factor Correction