Isolated Boost Type Resonant Converter With Fixed Frequency PWM and Load-Independent Voltage Gain

This article proposes an isolated boost type resonant converter (IBTRC) with fixed frequency pulsewidth modulation (PWM), which has load-independent gain characteristics. Only one magnetic component and two active switches are used in the proposed IBTRC. Therefore, compared with the two-stage converter and the current-fed resonant converter (CFRC), the number of magnetic components and switches of the proposed IBTRC is reduced. Moreover, with the proposed modulation, the converter obtains the benefits of load-independent voltage gain characteristics. Under wide load and voltage range, all switches can realize zero-voltage switching (ZVS) and all diodes can realize zero-current switching (ZCS). The operation mode, characteristics, and parameters design process of the proposed solution are also described in detail. Finally, a 600-W prototype is built to verify the validity and the advantages of the proposed scheme.