Multiple-input soft-switching converters in renewable energy applications

This paper proposes a method that can reduce component counts of isolated multiple-input converters. This method can be applied not only to hard-switching converters but also soft-switching converters such as full-bridge (FB) converters. Two types of multiple-input (MI) FB converters that are generalized with a component counts reduction method are also proposed in this paper. Circuit operation, power sharing among input sources, and soft-switching conditions of the proposed MI-FB converters are discussed with a resistive load. Different control rules could be selected for uni-directional or bi-directional applications. A prototype of the proposed MI-FB converter was built in order to verify the analysis. It is observed that the measured inputs-to-output voltage ratio matches with the analysis. In addition, soft-switching characteristics on input switches are observed in the proposed MI-FB converter.