Digital implementation of load sharing method for interleaved LLC converters
LLC converter has been found advantageous in isolated DC-DC applications due to its high efficiency and low cost. However in high-power high-current applications, the high component stress and high conduction loss limit the maximum power capacity and reduce the efficiency. Interleaving technique can be employed to solve this problem, but the component tolerances of the resonant tanks will cause severe load sharing problem. This paper describes digital implementations of switch-controlled capacitor (SCC) modulated multiphase LLC converters (SCC-LLC) to achieve load sharing. A 600W two-phase interleaved SCC-LLC prototype is built to demonstrate the feasibility and advantages.