Interleaved multicell semi-bridge rectifiers for cascaded H-bridge multilevel converters

This paper introduces a new approach to generate the dc-link voltages for a cascaded H-bridge inverter using interleaved single-phase multicell semi-bridge rectifiers. Compared to previous approaches, the presented solution improves input current low-order harmonic performance, reduces input current switching harmonics, and achieves higher overall efficiency. A simple rectifier control strategy is also presented that supports cascaded H-bridge inverters operating with phase-shifted carrier pulsewidth modulation. Matching simulation and experimental results using a two-cell semi-bridge rectifier phase-leg are included to verify the theoretical concepts.