Resonant technique for bidirectional flyback converter

Proposed is an improvement of the bidirectional flyback topology, proposing a resonant inversion of the output polarity voltage. The topology is applied to supply high pressure sodium lamps with a low frequency symmetrical square waveform, in order to avoid the acoustic resonance phenomenon occurrence. The resonant technique developed guarantees zero current switching commutation during the inversion stages, increasing around 15% the overall efficiency and decreasing voltage and current stresses on the switches. The proposed topology has been implemented and validated by experimental results.