Automatic current-sharing method for multi-phase LLC resonant converter

An automatic current sharing method is proposed for multi-phase LLC resonant converter for high power application. There are two types, one is common inductor, and the other is common capacitor. Automatic current sharing is achieved by using a common component for all LLC resonant stages. The proposed method can automatically share the load current without any additional circuit and control strategy. The current share performance of the proposed method is analyzed under Fundamental Harmonic Analysis (FHA) assumption. A 600W two-phase LLC converter prototype based on the proposed method is built to verify the feasibility. Excellent current sharing performance has been achieved.