Study On Maximum Power Point Tracking Of Partially Shaded Photovoltaic System

With fast-pace development of social economy, the weakness of traditional energy source is increasingly apparently from energy crisis to environmental pollution. For the aim of sustainable development, the exploitation and application of renewable energy resource draw more and more attention all over the world. In this area, solar power, which epitomizes the non-pollutant energy, forms the basis energy. The research of such area is specialized and soaring.PV system will be concealed by cloud, building and other objects in reality and therefore cause shadow effect. In shadow, PV system may cause Hot spot effect and burn the battery. Bypass diodes is used for solving Hot spot effect but since it could change the output character of PV system, multiple peaks would appear in P-V characteristic curves. Such peaks may result in the low efficiency or even dysfunction of MPPT(Maximum Power Point Tracking) designed in sole peak model.The study is mainly focus on the principle of PV battery and the output character in the non-uniformed condition. Combined with former reference, the study also summarizes the current studies of PV electricity generation and designs an improved MPPT algorithm. We verify the algorithm in simulation based on Matlab/Simulink and the final double-peak MPPT algorithm is finished in 200W Interleaved flyback micro-inverter by the help of TI DSP. Associating with traditional sole-peak MPPT, the new-designed MPPT which focuses the conditional judgment in partial shaded could get the global MPPT fast and steadily. The whole algorithm can be verified in interleaved flyback micro-inverter we designed.