AC-DC single-switch three-phase converter with peak current control for power LEDs

This paper presents the development of a three-phase AC-DC flyback converter without electrolytic capacitor with power factor correction applied on street lighting using power LEDs. Recent studies suggest that the lifetime and reliability of an electronic ballast can be improved removing the electrolytic capacitors, considering that the lifetime of these devices has strong influence of the operating temperature. A single-switch three-phase topology is proposed, and a prototype is developed. The experimental results prove the feasibility of this technology in electronic ballasts for LEDs. The prototype has an output power of 54 W, power factor of up to 0.99 and efficiency up to 77%, depending on the operating conditions. This prototype can operate in a wide range of input voltages and also has a peak current control strategy, which reduces design costs due the using of a low cost controller.