A single-stage buck-boost three-level neutral-point-clamped inverter for the grid-tied photovoltaic power generation

This paper proposes a novel single-stage buck-boost three-Level NPC inverter for the grid-tied photovoltaic (PV) system, which can effectively solve the unbalanced operational conditions generally appeared between two coupled independent PV sources induced by the unequal irradiation and temperature distribution. The proposed control scheme can simultaneously guarantee the maximum power point (MPP) operation of both PV sources and maintain the output waveform quality. Matlab simulations are presented to show the performance of the proposed inverter.