Abstract
A novel three-level inverter has been proposed in this paper for PV applications. This inverter can boost the input photo-voltaic (PV) voltage up to three times in output without additional DC/DC converter. Two switched-capacitor (SC) cells are connected in a cascade manner to boost the input PV voltage. Further, this topology can eliminate the leakage current completely, as it bypasses the parasitic capacitance by way of a common ground (CG) connection between the negative terminal of the PV panel and the neutral of the grid. Consequently, it does not need an electro-magnetic interference (EMI) filter for electromagnetic compatibility (EMC). The additional feature of the proposed inverter is reactive power handling capability. A proportional + resonant (PR) current controller has been implemented to regulate the active and reactive components of the grid current. The proposed modulation strategy makes the inverter capable of balancing the switched capacitors by charging during its inactive state. The inverter operating principle, operating modes, and modulation scheme have been analyzed in detail. The various claims about the proposed inverter have been verified in MATLAB® simulation, and the results are presented.