Research On The Maximum Power Point Tracking Of Stand-alone PV Power Generation System

With the development of economy, the demand for energy is increasing, while thetraditional non-renewable energy,sources are depleted day by day, and seriousenvironmental pollution is caused in the application process, so green energy came intobeing.With the development of photovoltaic (PV) technologies, applications ofphotovoltaic have grown rapidly, indicating that the photovoltaic are attractive toproduce environmentally benign electricity for diversified purposes. In order tomaximize the use of solar energy, this thesis focuses on the PV power generationsystems, which includes modeling of PV systems, maximum power point tracking(MPPT) methods for PV arrays.The modeling of PV arrays is the base of research on PV systems. This thesispresents simulation model of PV arrays based on the output characteristics formulas. Itcan be directly applied in circuit simulation and system analysis.Maximum Power Point Tracking (MPPT) method is an important means to improvethe system efficiency of PV power generation system. MPPT theory and various MPPTalgorithms are introduced in the literature. Furthermore, The simulation study of BoIBBcircuit applied in the MPPT is completed based on Simulink simulation model. Basedon those researches, this thesis proposes a novel implementation of a variable step P&Oalgorithm. In steady state，the both methods are similar，but the variable step P&O thatuses a large step can ensure the accuracy of the algorithm. At the same time, thesimulation results verify that the novel MPPT algorithm can track PV array’s MPPefficient, even under the circumstance of isolation level, ambient temperature changingrapidly.