Three-Leg Asymmetrical Voltage Resonant Converter for Multiple LED Load Applications with Independent Dimming Control

In this paper a new three-leg asymmetrical voltage resonant converter is proposed for multiple LED load applications. The converter is developed with leg-1 has common for both LED loads. The main contributions of the proposed work are: (1) Independent dimming control of LED loads, (2) Zero Voltage Switching (ZVS) of all the power switches, (3) High efficiency and (4) Regulation with asymmetrical voltage control. To achieve independent dimming control, the PWM dimming is employed with leg-2 and leg-3. Two resonant circuits are connected in the proposed circuit. Owing to this all the power switches operate with zero voltage switching which reduces the switching losses, resulting in higher converter efficiency. The loads can be regulated using asymmetrical voltage control. The threshold voltage for the LED loads is supplied with battery source, therefore power processing of converter is reduced. The operating modes and steady-state analysis of the proposed converter are presented in detail and verified by using the MATLAB Simulink environment.