An Investigation into a ZVS Resonant Converter to Achieve Wide Voltage Operation

An Investigation into a ZVS Resonant Converter to Achieve Wide Voltage Operation

A new zero voltage switching LLC resonant converter is presented to have the feature of wide-voltage input operation. Thecircuit configuration of the presented circuit topology has two converter legs on the input-side to lessen voltage rating on powersemiconductors and two secondary windings on low-voltage side to implement wide input voltage capability. Two split resonantcapacitors are connected to resonant tank to better achieve soft switching turn-on for active semiconductors. Two different secondaryturns were adopted to have low (or high) voltage gain under high (or low) voltage input. Thus, the studied circuit topology couldachieve wide zero voltage switching load range and wide voltage input condition. The effectiveness of the presented circuit topologywere evaluated and confirmed by the test waveforms with an 800 W prototype with Vin = 260 V to 800 V.