The partial shading of photovoltaic (PV) modules caused by factors such as trees, clouds, and dust, as well as varying degrees of aging among PV modules, will lead to mismatched electrical characteristics of series PV modules and result in a significant power loss in the PV system. Differential power processing (DPP) converters can be employed to improve the power generation under partial shading conditions for a PV system. Nevertheless, a DPP converter is usually an additional device to the existing PV system and will introduce extra power losses and expense. In this paper, a single-stage boosting inverter (SSBI) integrated with a multi-winding type DPP converter is proposed. The functions of maximum power point tracking (MPPT), voltage step-up, inversion, and power equalization are achieved in one power stage. Only four switches are employed to achieve the above functions, resulting in a simple circuit and low cost. The feasibility of the proposed topology is verified by simulations and experiments. The experimental results show that, compared with SSBI without an integrated DPP structure, the proposed topology can have 12.83 % and 60.51 % power increment under two different partial shading conditions and good quality sinusoidal output with total harmonic distortion (THD) of 4 %.
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