A Research Of MPPT Implementation Strategy Based On The Constant Voltage Method And The Impedance Matching Method

With the continuous development of society, the people’s living standardsimproved, and the disadvantages of the traditional energy have increasingly appear,such as pollution to the environment is more and more serious, oil, coal, and natural gasconventional fossil energy irrefragable because, to meet people of the huge demand forenergy, this has become the main world important bottleneck of the economicdevelopment. At present, many countries began looking to new energy development andutilization. Solar energy as the one kind of emerging energy, reproducibility and nopollution because characteristics, such as the high attention by people. But because ofsolar cells conversion efficiency is low, and solar Power high cost, for in the differentexternal conditions output as many of the electric energy, improve the efficiency ofsolar cell transformation, and puts forward the Maximum Power Point Trackingtechnology (Maximum Power Point Tracking, MPPT),MPPT can make full use of solararray, reducing the cost of solar power system. Solar power in the form of a variety of,including photovoltaic power generation, light sensor power generation, photochemicalpower and light biomass power four forms, At present, the photovoltaic powergeneration technology has become the mainstream of the solar energy application, Inthis paper, photovoltaic power generation in the DC/DC boost circuit, MPPT and so adetailed research.The main research contents are as follows:First introduced the photovoltaic system research background, significance, as wellas the domestic and foreign situation of photovoltaic power generation and developmentprospects, and the photovoltaic grid-connected system were introduced.And then to the photovoltaic cell basic principle and output characteristic to carryon the simple analysis, the main circuit adopts Boost DC/DC converter, Boost circuitworking principle is analyzed in detail, and some important parameters in the circuit areselected.Finally, aiming at the photovoltaic system maximum power point trackingtechnology research, photovoltaic systems of several commonly used control algorithms,such as constant voltage tracking method (Constant Voltage Tracking), and perturbationand observation method (Perturb&Observe algorithms, P&Q), incrementalconductance method (Incremental Conductance Method), fuzzy control method (Fuzzycontrol) to analyze the advantages and disadvantages, Presents a new MPPT controlalgorithm, the algorithm is near the maximum power point using impedance matchingmethod, away from the maximum power point, the use of constant voltage trackingmethod to quickly reach the maximum working voltage. And the use ofMatlab/Simulink simulation software to establish photovoltaic system simulation model,simulation results show that the control strategy has good speed and stability.