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This study presents a new DC/DC converter for high input voltage and high load current applications. To adopt low voltage rating power devices in high voltage applications, two split capacitors with four active switches are used in the primary side to reduce the voltage stress of power switches at V in /2. Two flying capacitances are used to automatically balance two split capacitor voltages in every switching cycle. The proposed converter includes two resonant circuits to share the load current and to reduce the current stress of passive components. If the switching frequency is less than the series resonant frequency, power switches can be turned on under zero-voltage switching and rectifier diodes can be turned off under zero current switching. Therefore the switching losses on power semiconductors are reduced. The interleaved pulse-width modulation is adopted to further reduce the ripple current at output side. Thus, the output filter inductances can be reduced. Finally, experiments with a 1.2 kW prototype are provided to verify the effectiveness of the proposed converter.

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This paper presents a new DC/DC converter for high input voltage and high load current applications. In order to adopt low voltage rating power devices in high voltage applications, two split capacitors with four active switches are used in the primary side to reduce the voltage stress of power switches at V in /2. Two flying capacitances are used in order to automatically balance two split capacitor voltages in every switching cycle. The proposed converter includes two resonant circuits to share the load current and to reduce the current stress of passive components. If the switching frequency is less than the series resonant frequency, power switches can be turned on under zero voltage switching and rectifier diodes can be turned off under zero current switching. Therefore, the switching losses on power semiconductors are reduced. The interleaved pulsewidth modulation is adopted to further reduce the ripple current at output side. Thus, the output filter inductances can be reduced. Finally, experiments with a 1.2kW prototype are provided to verify the effectiveness of the proposed converter.

This paper presents a new zero voltage switching (ZVS) converter with the full-bridge and halfbridge circuits. The main advantages of the proposed converter are wide ZVS range for all leading-leg and lagging-leg switches, low circulating losses and low output inductor size. The drawback of narrow ZVS range of lagging-leg switches in conventional phase-shift pulse-width modulation full-bridge converter is improved by adding a half-bridge circuit shared the lagging-leg switches with the full-bridge circuit. Therefore, all switches in the proposed converter can be turned on at ZVS from low light to full load. The output of half-bridge converter is connected to the secondary side of the full-bridge converter in order to generate a positive voltage instead of zero voltage at the secondary rectified point. Hence, the high circulating losses in conventional full-bridge converter is overcome and the output inductor current ripple is also reduced. Finally, the theoretical analysis and performance of the proposed converter are verified by the experimental results from a 1.44kW prototype. Index Terms-Hybrid DC/DC Converter, Full-Bridge, Half-Bridge, ZVS.