In-depth Analysis of current-fed resonant Full-bridge Converter Application for high voltage DC Power Supply

In this paper, analysis of cascaded current-fed full-bridge DC/DC converter with resonant switching and constant on-time control operating with high voltage (HV) multiplier on the secondary side is presented. Using 300kV 600W bipolar power supply as a design example, interaction between current source implementation and DC/AC stage of the converter is analyzed using simulation. Impact of the HV transformer and multistage multiplier on the converter design and resonant switching characteristics is shown. Simulation results are compared with measurements on oil-insulated 150kV/300W unipolar high-voltage power supply prototype, discrepancies discussed and opportunities for future work identified.