| In a multitude of new energy sources, solar energy as one of the cleanest, mostabundant energy reserves, attracted wider attention. But the main problem of the newenergy sources such as solar energy and wind power is their low efficiency and unstableoutput. This requires the utilize of advanced control methods to maximize its efficiencyand stability, hence enable them truly serve the people.While this paper mainly focus on maximum power point tracking of PV arrays, basedon the traditional model for photovoltaic cells, the shadowing condition of PV arrayoperation mode is taken into consideration, and thus to expand the concept to the outputcharacteristics of non-uniform illumination, and the method of maximum power pointtracking under non-uniform illumination conditions is investigated here.Under the research on several common control methods on maximum power pointtracking currently exist, the traditional control method of maximum power point tracking:Constant Voltage Tracking Method （CVT）, the Perturbations and Observtion Method（P&O）, Conductance Increment Method(InC), does not apply to maximum power pointtracking in unevenly lighting conditions. Due to uneven illumination, the outputcharacteristics of the photovoltaic array is a multimodal curve with several peaks, ratherthan a unimodal curve, it is easier to bring the system into a local maximum power point,while not the global maximum power point. In this case, a new control method is neededto achieve maximum power point tracking under non-uniform illumination conditions.This essay applies the fuzzy control method to maximum power point tracking of PVarrays, and based on the characteristic of the photovoltaic array itself, a new type of moresuitable for photovoltaic array based on Adaptive fuzzy control algorithm is introduced.Through the simulation, proposed method can not only accurately tracks the globalmaximum power point, but also can reduce the oscilation near MPPT. |
PDF Full Text Request