Active Snubber Solution for an Interleaved Flyback Converter

This paper presents an energy-recovering active snubber in which the energy captured by the snubber capacitor is transferred back to the converter’s input using an auxiliary inverting switching stage. The snubber operates independently of the main power stage and can therefore be applied to a wide range of isolated converter topologies without modifying their primary control or structure. The proposed snubber achieves an energy-recovery efficiency of approximately 80%, thereby reducing snubber-related losses by the same proportion. As a representative implementation, the concept was experimentally validated in a 550 W dual-phase interleaved DC–DC flyback converter, where it improves the overall converter efficiency by 1.6 percentage points and reduces total losses by 18% compared with a dissipative snubber solution. The proposed snubber supports a wide input-voltage range and is well suited for multiphase converters, as most of its components can be shared between phases.