A Novel Multiresonant DC-DC Converter With Wide Output-Voltage Range

A novel multiresonant dc-dc converter with notch filter function is proposed in this article. The converter can regulate the output voltage over a wide range and has significant advantages in terms of gain. Due to its gain characteristics, the multiresonant converter has better inherent soft startup capability and over-current protection function. In addition, the switches of the converter can realize zero-voltage switching over the entire output-voltage range, and the output rectifier diode can realize zero-current switching. Compared with the traditional LLC converter, the multiresonant converter can use third harmonic to transmit the active power, and the loss caused by the reactive power cycle of the converter is reduced, which improve the efficiency. The converter parameters are optimized from the perspective of gain and efficiency in this article. Finally, a 2.5-kW experimental prototype is designed and the peak efficiency is 97.27%. The correctness of the theoretical analysis and the rationality of the parameter design are proved by the experimental results.