A high power and high efficiency PC power supply topology with low cost design to meet 80 Plus Bronze requirements

In this paper, the soft-switching LLC half-bridge resonant converter with frequency control is proposed and used in desktop ATX PC power supply applications. The new proposed simple structure of PC power supply with two transformers and multi-output resonant converter has the features of frequency modulation operation with fixed duty cycle, zero voltage switching (ZVS), and low voltage stress in the active switches and output diodes. Moreover, it can achieve high power density, high efficiency, low switching losses and low component counts, which make the ATX PC power supply operation to meet 80 Plus Bronze requirements and cost effective. In the paper, the new ATX PC topology is presented, and a specific example for PC 550W application is designed and implemented to verify its feasibility.