Impact Of Micro-Climate On The Performance Of Photovoltaic Array

The application scale and area of the photovoltaic energy technology, as the representative of renewable energy, is expanding largely. With global environment problems becoming increasingly serious, the research of photovoltaic energy and environment engineering is becoming increasingly more and more significant.Based on Donghua University5.1kW photovoltaic power generation system experimental platform, the photovoltaic array of household micro-grid photovoltaic power generation system is taken as the study object in this paper. Design of the independent/grid-connected dual-mode photovoltaic monitoring apparatus has been completed. The impact of micro-climate on the performance of photovoltaic array has been quantitatively analyzed on the basis of the processing and analysis of monitoring data from Donghua University5.1kW photovoltaic power generation system and by applying three methods, i.e. MATALB/Simulink simulation method, numerical method, regression analysis method.In the first place, the principle of photovoltaic power generation system, coupling with the structure of photovoltaic array has been stated in this paper. The design of independent/grid-connected dual-mode photovoltaic monitoring apparatus, together with the basic concept of micro-climate has also been described.Secondly, the MATLAB/Simulink simulation model of photovoltaic array has been established on the basis of the photovoltaic array engineering mathematical model and combing with the specific parameters of photovoltaic array applied in Donghua University5.1kW photovoltaic power generation system. Subsequently, making full use of monitoring data from Donghua University5.1kW photovoltaic power generation system, the model has been optimized considering the impact of the three micro-climate variables by comparing the model simulation values with measured ones. Five optimized models, of which accuracy have also been analysis, have been presented, and the most optimal model has been declared.Thirdly, a simple correlation correlating operating temperature with the three environment variables is validated by Donghua University5.1kW photovoltaic power generation system. The cell-to-module-to-array mathematical model for photovoltaic panels has been built, which is resolved by the method defined as segmented iteration. After resolving the model, I-V curves and P-V curves of photovoltaic array under different kinds of working conditions can be obtained, which is made comparison with the measured values. The impact of micro-climate on the characteristic curves of single-crystalline silicon photovoltaic array is analyzed by observing the calculated I-V curves and P-V curves.Finally, the numerical model and regression model of maximum-output power taking the three micro-climate variables into consideration has been set up in this paper to quantitatively analyze the impact of micro-climate on the maximum-output power of single-crystalline silicon photovoltaic array. The methodology of stepwise regression is adopted to analyze the significance level of the impact of the three environment variables, which include solar irradiance, ambient temperature, and wind speed, as well as module temperature on the maximum power output of PV array.In this paper, a variety of analysis methods, including MATLAB/Simulink simulation method, numerical method and regression method are applied to quantitatively analyze the impact of micro-climate variables, i.e. solar irradiance, ambient temperature and wind speed, on the performance of photovoltaic array working under different conditions. The study of this paper has important significance to the research of photovoltaic energy and environment engineering.