TRANSFORMERLESS SWITCHED-CAPACITOR INVERTER WITH REDUCED NUMBER OF SWITCHING COMPONENTS FOR PV APPLICATION

A novel transformerless switched-capacitor (SC) inverter with minimum part count and reduced voltage stresses is proposed in this paper. The suggested inverter generates a five-level waveform using nine switches, two capacitors, and a diode. Design description, working principle, and control techniques are described in detail. Some of the most remarkable properties of the proposed architecture are its ability to increase the input voltage while keeping zero leakage current and its self-balancing capabilities of the capacitors. A comparison to prior-art topologies demonstrates the suggested topology benefits. Lastly, a laboratory prototype has been built to check its feasibility and effectiveness.

Keywords:

Transformerless inverter, leakage current, component count per level.

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