A Novel LLC Resonant Converter With Configurable Capacitors in Output Stage for Wide Output Voltage Range Operation

The traditional LLC converter with variable switching frequency achieves wide output voltage range operation, but it is companied by the issues of reduced efficiency and difficult magnetic component design. To overcome these issues, a novel LLC converter with configurable capacitors in the output stage is proposed. It realizes two-times adjustment of output voltage by simply arranging the configurable capacitors in parallel or series in pulsewidth modulation manner. As compared to prior art, it reduces the output inductor, power losses, and switch capacity by 50%, 15.6%, and 5.7%, respectively. The experimental results obtained from a 100-V 1.5-kW setup verify the feasibility of the proposed converter.

Automated summary

The traditional LLC converter with variable switching frequency suffers from reduced efficiency and difficult magnetic component design. A novel LLC converter is proposed, which utilizes configurable capacitors in the output stage to achieve two-times adjustment of output voltage. Compared to prior art, it reduces the output inductor, power losses, and switch capacity.