An Improved H6-Type Single-Phase PV Inverter with Suppressed Leakage Current

In low-power grid-connected photovoltaic (PV) systems, as the dominant area of them is regularly outreaching all around the world in the last decade, transformerless inverters are competently accepted because of their higher efficiency, lighter weight, smaller volume, and lower cost contrasted to PV inverters that possess the transformer. However, the challenge of hazardous capacitive leakage current in transformerless topologies should be carefully addressed. Further, according to grid standards, reactive power feeding capability must be applied by the smart grid-connected PV inverter to support the grid. In this paper, In order to meet these requirements, an improved H6-type topology, namely IH6-BDC inverter, is proposed for single-phase grid-connected operation, in which a bi-directional diode clamping cell is used to improve common-mode (CM) characteristic. The suggested inverter is simulated utilizing MATLAB/Simulink environment to verify the professed approach's performance. Further, loss analysis using the PSIM software is adopted to accredit the efficiency of the suggested inverter structure. The simulation consequences show 97.91% efficiency at 3.1-kW rated power with a 20 kHz switching frequency.