A hold-up time extending method for asymmetrical half-bridge converter

For asymmetric half-bridge converters, one of drawbacks is pretty narrow input voltage range, whose reasons are a leakage inductance for ZVS, its switches configuration and a blocking capacitor for clamping power switches with the input voltage. Therefore a hold-up time is more quite restricted for others. In this paper, it will be analyzed for a voltage conversion ratio of the converter. And a way to extend hold-up time for the converter will be shown. Finally, an asymmetrical half-bridge converter will be tested with 24V / 8A of output specification to verify the way.