Novel Automatic Current Balancing of Two-Phase Isolated Buck-Boost Converters

This article presents a family of the two-phase isolated buck-boost dc-dc converter with an automatic current balancing feature inhering from the series-capacitor (SC) high conversion ratio converter. The current of each module is automatically well-balanced regardless of the gate signals mismatch and different characteristics of the semiconductor switches utilized in the proposed converter. In addition, the SC combined with the two-phase current-fed full-bridge converter is typically analyzed in this study. To further enhance the reliability, the proposed converter with clamping voltage overshoot action is introduced. Moreover, the design parameters, equivalent circuits, switching schemes, and operation modes of the proposed dc-dc converter are described in detail. The current balancing principle of the two inductor currents in the designed converter is also explained. Furthermore, the performance of the proposed converter is analyzed in PSIM simulation. Lastly, a hardware prototype with a rated power of 2 kW was built and tested in different operating conditions to validate the analysis and effectiveness of the presented converter.