An improved active-clamp ZVS forward converter with a lossless snubber

Active asynchronous secondary side voltage clamping

“…In steady state conditions, the absorbed energy must be removed from the clamp capacitor by the next switching cycle. Dissipative clamps simply dissipate the energy [1], whereas non-dissipative clamps recover most of the energy to the input or output of the converter [2], [3], [4], [5]. Generally, low power converters can suffice with a simple dissipative clamp, whereas the resistor dissipation in medium and high power converters may warrant the additional complexity of a non-dissipative clamp [1].…”

“…In other clamping circuits, the capacitor reset operation is typically synchronized with the converter [2], [3], [4], [5], thereby imposing a lower limit on the inductor size. The proposed clamping circuit operates asynchronously from the main converter, thereby enabling use of a higher switching frequency and drastically shrinking the size of the passive components in the clamping circuit.…”