A New Passive Lossless Snubber

Galvanically isolated photovoltaic (PV) microinverters based on single-stage flyback topology have advantages: simplicity, better reliability, and low cost. But isolated flyback topology comes with voltage stresses on semiconductor switches caused by transformer leakage inductance. An improved regenerative snubber has been proposed to meet the ever-growing demand for higher efficiency of PV microinverters. The proposed topology is the inductor-capacitor-diode (LCD) snubber with flying capacitor modified to reduce circulating currents. Theoretical analysis reveals a number of advantages. Experimental results are presented to verify the performance.