Research On Engineering Analytical Model And Maximum Power Point Tracking Of Photovoltaic Modules

Due to frequent occurrences of extreme weather climate events and drying up of conventional energy such as oil and coal, new energy power generation technology has become the focus of the whole world for the past few years. Photovoltaic power generation with its clean, safe, renewable characteristics has become a significant branch of new energy power generation. Photovoltaic power generation which is a strategic emerging industry is of great significance to adjust energy structure as well as to promote energy production and consumption patterns changing and the construction of ecological civilization in our country. Since accurate element model is the basis of power system simulation and analysis, to easily and quickly predict the output characteristics of a photovoltaic module which is the component of a photovoltaic power station under any environment has great value of engineering application. Summing up the above, engineering analytical model and maximum power point tracking of photovoltaic modules have been chosen as the main research contents in this paper.A classical single-diode physical model of photovoltaic cells with specific physical meaning parameters has an implicit transcendental output characteristic whose equation is difficult to solve. A new shape parameters mathematical model of photovoltaic cells based on fitting external characteristics with concise equation has shape parameters without specific physical meaning.An engineering analytical model is proposed combining advantages of above two models in this paper. Since physical performance of a photovoltaic module is changing with age, its output data under Standard Test Conditions (STC) are replaced by the measured ones under Real Test Conditions (RTC) fitted to get shape parameters under RTC, and analytical results of the output characteristics under any environment are obtained by getting shape parameters from correcting the physical parameters according to environmental change based on analytic relationship between above two kinds of parameters. Accuracy of the proposed model was validated through experiments performed for measuring the output characteristics of a mono-crystalline silicon photovoltaic module under typical outdoor environments.Output characteristics of photovoltaic modules under different irradiation levels, different cell temperatures and both of different irradiation levels and cell temperatures were stimulated and analyzed based on the proposed engineering analytical model. A synthesis algorithm combining the non-adaptive searching optimal algorithm based on the proposed engineering analytical model of photovoltaic modules and incremental conductance adaptive searching optimal algorithm was designed.