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This article presents a two-stage T-type hybrid five-level transformerless inverter (TLI) for grid-connected photovoltaic (PV) applications. The proposed T-type hybrid five-level inverter and its level-shifted pulsewidth modulation scheme offers reduced leakage current by eliminating the high-frequency variations and sudden transitions in the voltage across PV parasitic capacitance CPV and a path for the negative current in all the modes of operation under unity and nonunity power factor conditions of the grid without degrading the waveform quality. Moreover, in this article, the proposed inverter is integrated with a traditional three-level boost converter (3LBC) for boosting the lower PV voltage to higher dc-link voltage and also to extract maximum power from the PV source. The 3LBC provides high efficiency and reduced input inductor size for the same power rating over the conventional boost converter. The simulation results of the proposed system are presented using MATLAB software, and a 500-W experimental prototype is constructed and tested in the laboratory to validate the feasibility of the proposed configuration. Finally, a comparison of the proposed inverter with other five-level TLI topologies is presented to highlight its merits. [ABSTRACT FROM AUTHOR]

Summary: Transformerless inverters are becoming popular for grid‐connected photovoltaic applications due to their simplicity, reduced size, weight, cost, and higher efficiency. In this paper, a two‐stage hybrid transformerless multilevel inverter (MLI) for single‐phase grid‐connected photovoltaic power generation system (PVPGS) is presented. The proposed topology comprises a multilevel boost converter (MLBC) and a symmetrical hybrid MLI. MLBC combines the boosting and switched capacitor voltage functions to produce self‐balanced multiple voltage levels. The proposed MLI is derived from a combination of bidirectional switches, a half bridge, and a diode‐clamped branch, which can produce only two variations in the total common mode voltage and is capable of suppressing leakage current as per DIN VDE 0126‐1‐1 grid standards. It offers the advantages of scalability, reactive power capability, reduced total harmonic distortion, and filter size. The proposed hybrid transformerless seven‐level inverter is simulated in MATLAB, and experimental setup is built to validate the effectiveness of the proposed configuration. Finally, a comprehensive comparison is made with other seven‐level inverter topologies. This paper presents a two‐stage hybrid transformerless seven‐level inverter for single‐phase grid‐connected photovoltaic power generation systems. The proposed topology comprises a symmetrical hybrid multilevel inverter (MLI) and multilevel boost converter (MLBC). The MLBC combines the boosting and switched capacitor voltage functions to produce self‐balanced multiple voltage levels. It owns the advantages of modularity, reduced THD, filter size, and minimum leakage current with reactive power capability. The performance of the proposed configuration is validated through MATLAB simulation and experimental setup. [ABSTRACT FROM AUTHOR]