The parameter selection in the interleaved parallel Boost integrated LLC resonant converter significantly affects its efficiency due to the integrated design

and it is difficult to achieve high-efficiency operation over a wide input voltage range. To address the issue above

by theoretical modeling and experimental verification

we clarify the influence mechanisms of the parameters quality factor Q

resonant inductor ratio k

and Boost inductor ratio r on the converter’s losses

and propose a parameter design method that takes into account both efficiency and zero-voltage-switching (ZVS) realization. A quantitative model for the turn-on and turn-off losses of the primary switching transistor

the losses of the secondary rectifier transistor

and the losses of magnetic components is established. It is clarified that the increase of Q

k

and r can reduce the effective current value and turn-off losses

but it needs to be designed in a compromise with the ZVS condition and the voltage gain range. Further

a parameter collaborative optimization method that takes into account both efficiency improvement and ZVS realization is proposed. By constraining the energy of the resonant network and the charging and discharging characteristics of the parasitic capacitance

the loss suppression and the robustness of soft-switching are balanced. The above relationships are derived from the time-domain equation of the LLC resonant network and are independent of specific parameters

and the conclusion is universal. Experimental results show that the optimized converter achieves a peak efficiency of 96.46% over a wide input voltage range of 120~240 V

the full-load efficiency is higher than 88%

and the temperature rises of key components are all below 50 ℃

verifying the accuracy of the theoretical model.