A Three Leg Asymmetrical Voltage Resonant Converter With Independent Dimming Control for Multiple Load LED Lighting Applications

LED lighting has emerged as a global solution for sustainable industrial lighting. The three-leg asymmetrical voltage resonant converter has been designed for optimal performance in dimmable Light-emitting diode (LED) lighting applications. Its distinctive features, including enhanced efficiency, asymmetrical voltage regulation, Zero Voltage Switching (ZVS) of all power switches, and an independent dimming control strategy, make it well-suited for high-power LED lighting applications. The converter under consideration incorporates a common leg-1 to drive load-1 and load-2. So that, the load-1 and load-2 are powered by the asymmetrical voltage between leg-1 and leg-2, and leg-1 and leg-3 respectively. To enable independent dimming control, the voltages between legs are nullified by individual dimming levels. The proposed circuit incorporates two resonant circuits. This configuration ensures that all power switches operate with ZVS, effectively minimizing switching losses. Further, the threshold voltage of each LED load is supplied by the battery in turn resulting in a lower power processing of the converter. The detailed operational principle and design considerations are discussed. Moreover, the loss analysis, detailed comparison with similar works, and the efficiency analysis at different dimming conditions are presented. Finally, the effectiveness of the converter is verified in a MATLAB Simulink environment and an 80W laboratory prototype.