A Dual-Transformer-Based Isolated DC-DC Converter with Hybrid Voltage-Multiplier for Wide and High Output Voltage Applications

A dual-transformer-based isolated DC-DC converter with hybrid voltage-multiplier is analyzed and evaluated for applications requiring wide and high voltage range. With the help of using two transformers, the current and power flowing through them are equal, making the energy transmitted automatically balanced. Besides, with the combination of the three-leg hybrid rectifier and the voltage multiplier, high output voltage gain can be obtained and the voltage stresses on the secondary-side devices can be clamped to half of the output voltage. Meanwhile, soft-switching can be realized for all devices in a wide load range and the reverse recovery problem of the secondary-side diodes can be effectively solved, which improves the efficiency of the converter. To verify the advantages of the converter, performance of a 1-kW prototype is evaluated with experimental results.