A Method for Designing Resonant Tank of Half-Bridge Three-Level LLC Converter

With the advantage of the voltage stress is only half of the input voltage, the three-level converter has been widely used in the application fields of high power DC-DC power supply and electric vehicle. In the paper, on the basis of working principle of half-bridge three-level LLC resonant converter, the relationship among resonant tank parameters, dead-time and soft-switching conditions of power switches are discussed. Then a method for designing resonant tank of the half-bridge three-level LLC Converter is studied. Finally, a 3.3kW prototype is built to verify the theoretical analysis.