Non-Dissipative Regenerative Snubber for Isolated DC-DC Cuk Converter

This work presents a non-dissipative regenerative snubber solution having passive and active components for isolated DC-DC Cuk converters. The snubber suppresses the over-voltage produced across the main switch of the convert during the turn-off interval, intrinsic of the topology and caused by the leakage inductance of the transformer. This regenerative snubber, instead of being connected in parallel with the main switch as a conventional passive and dissipative snubber, is connected directly to the terminals of the transformer which allows the snubber capacitor to not be discharged through the switch at every switching cycle, reducing device turn-on losses and stresses. A passive and active approach of the proposed snubber is presented, analyzed, and studied. The validity and effectiveness of the proposal is demonstrated by simulation and experimental results on a 2.5-kW DC-DC isolated Cuk converter prototype.