Current Sharing Control of Multi-Input Modular DC-DC Converter Using Unregulated LLC Resonant Converter

Abstract

By applying an unregulated LLC resonant converter to a multi-input modular DC-DC converter (MIMC), the LLC converter can be operated at an optimal frequency while achieving power source flexibility. However, the output characteristics of an LLC converter are easily affected by the resonance parameter, and when connected in parallel, the output current is unbalanced. In this paper, we propose a current sharing control method to solve the current imbalance problem, and automatically balance the output current of each module. The effectiveness of the proposed current sharing control method is verified by simulations and experiments.