Zero voltage switching with reduced current stress for LED lighting applications

Abstract

Lighting systems using light emitting diode (LED) have drawn significant attention across the world. Nevertheless, to maintain a steady light output, these systems necessitate constant current regulators. This article proposes a buck–boost integrated zero voltage switched full-bridge LED converter with low current stress. It powers two identical lamps and a lamp of power rating twice the identical lamp. A direct current voltage source, arranged in series, transmits a portion of light power without conversion. A regulated low power output is provided using a complete bridge converter. The semiconductor switches off the full-bridge converter carry minimal current. This characteristic lowers conduction losses. The suggested converter facilitates dimming operation via on–off control and zero voltage switching, leading to minimal switching losses. Further input voltage of full-bridge converter is modulated to maintain constant LED lamp current. The detailed steady-state analysis and implementation of the proposed full-bridge LED converter with dimming control operation is presented here.