Switched-boost network-based single-phase boost DC-AC converter

This study proposes a new single-phase boost DC-AC converter based on the switched-boost network. The proposed converter has the following features: (i) the input current is continuous; (ii) the input and output share the same ground; and (iii) the output voltage waveform has only three levels (positive, zero, and negative levels). Compared with the conventional single-phase half-bridge Z-source inverter (HB-ZSI), the proposed converter uses one additional active switch, but fewer inductors and capacitors. In addition, the peak output voltage of the proposed converter is twice that of the HB-ZSI for the same shoot-through duty cycle. The operating principles, parameter design, small-signal analysis, and comparison with the single-phase HB-ZSI are presented. The simulation and experimental results are shown to verify the operating theory of the proposed converter. Finally, an isolated boost DC-DC converter is developed in the experiment with 42 V input and 600 V output as an example for the application of the proposed converter.