An active-clamping single-stage DC-AC flyback converter

This paper proposes an active clamping dc-ac flyback converter suitable to be used as a microinverter in renewable energy applications. The main features of the topology are the relatively low component count, high-frequency isolation, voltage step-up capability and zero voltage switching. The active clamping allows to recover most of the energy stored in the flyback's inductor leakage inductance and thus an improvement on the system efficiency is achieved. A 500 W, 50 kHz, 70 V input voltage and 127 Vrms output voltage prototype was built and the experimental results validate the theoretical analysis and the feasibility of the proposed converter.