A novel integrated interleaved dual-mode time-sharing inverter (IIDMI) is proposed for the grid-tied transformer-less photovoltaic (PV) applications. While, the dual-mode time-sharing conversion technique ensures minimum losses, the IIDMI also retains the advantages of interleaved topologies, such as low total harmonic distortion of the AC current with reduced filtering requirements, increased power density and reduced current and thermal stresses of power devices. Besides, the leakage current problem, which is a main concern with the transformer-less PV inverters, is solved by increasing the frequency of the main side band of the common mode voltage above the resonance frequency of the common mode impedance, while avoiding high switching losses. The current control, especially at transitions between the buck and the boost modes of operation is highly improved by utilizing a fast response dead-beat control (DBC) scheme. The working principles of IIDMI are explained in details and a 2.2-kW experimental prototype is implemented to confirm the theoretical achievements.

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