Single Stage Boosting Inverter with Multi-Winding Equalizer for Photovoltaic Applications

Mismatch faults of photovoltaic (PV) modules causing by partial shading in series PV system will lead to a serious drop in power generation. Unless the full power processing converters handling all the generated power, the differential power processing converters only deals with the mismatched power between PV modules, thus, differential power processing (DPP) converters usually have low power loss, high efficiency and relatively low cost. 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 integrated with a multi-winding type DPP converter is proposed. The functions of voltage step-up, inversion and power equalization are achieved in one power stage. The operating principle and control method of the proposed topology is described in detail. The feasibility of the topology is verified by simulation with a 17.13% and 66.99% power increment under two different partial shading conditions and good quality sinusoidal output.