Research On Multi-peak Maximum Power Point Tracking Control Strategy Based On Modified Fruit Fly Optimization Algorithm

In a practical engineering application of photovoltaic(pv) power generation systems, pv array’s surface is prone to partially shaded. When pv array is partially shaded, its output characteristic curve varies a lot.Traditional tracing methods are easily to fall into partial maximum point,thus this paper researches the pv array’s maximum power point tracking(MPPT) results in detail under different shadow conditions. This paper mainly researched the following aspects.(1) The mathematical and engineering model of the photovoltaic array is established by analyzing the internal physical characteristics of PV cells.A mathematical model is established under shadow conditions on the basis of former researchment. A simulation module is established with Matlab/Simulink tool, the pv array’s U-I and U-P output characteristic curve is obtained by the simulation model. According to the data,distribution regular of U-P peak curve is summarized. The question that should be considered in installation and design of PV array according to the distribution regularity of PV array is proposed in this paper.(2) Comparison and analysis has been made between some traditional MPPT methods in different situations. The fly optimization algorithm’s function principle, application field and algorithm steps are introduced in detail. An improvement has been done to this algorithm and a test function is used to verify the improved algorithm. The simulation result shows the improved fruit fly optimization algorithm has a better optimization performance and faster global convergence speed.(3) A 5.5kw simulation model of photovoltaic systems is built byusing Matlab/Simulink. Photovoltaic array output peaks in normal light and partial shadow cases are analyzed, through simulation analysis with the existing PSO algorithm and the modified fruit fly optimization algorithm, it verifies that the modified fruit fly optimization has better tracking performance in multi-peak PV array application, it is concluded that the improved algorithm of fruit flies can effectively improve the peak of the photovoltaic array output power.