Input Regulated Soft Switched Ripple Free Current LED Driver

This paper furnish an input voltage controlled full-bridge inverter based LED driver. A Double-ended forward converter(DEFC) is used along with full-bridge inverter to regulate the input of full bridge inverter for variations in the supply voltage. Input voltage to the full bridge inverter is sum of primary DC voltage and output of DEFC. Input to DEFC is from primary source. Supply obtained for the proposed configuration can be from DC micro grid. Thus the full bridge inverter is operated with fixed frequency and fixed duty ratio to achieve ZVS over wide range of input voltage variations. Full bridge converter with interleaved operation of output inductor currents is used to achieve ripple free constant current for LED string. In this configuration, power processed by DEFC is low which doesn't influence significantly, the overall efficiency is expected to be high. The proposed circuit configuration analyzed and simulation results are presented.