Design And Implementation Of A Power Router Based On Photovoltaic Power System

Pollution-free and renewable solar energy can be converted into convenient storage power by photovoltaic power generation technology,people pay more and more attention to it now because of serious global energy shortages and environmental pollution.However,partial shadow or uneven illumination of photovoltaic array not only significantly leads to a large drop in output power,but also causes the hot spot effect of components,which is not conducive to the safe operation of photovoltaic system.In order to reduce the influence of shading on the output power of arrays,a power router that be able to realize partial reconstruction of arrays is designed in this paper.By analyzing the influence of shading on the output power of series parallel photovoltaic array,a partial reconstruction method of arrays is proposed.The photovoltaic data acquisition peogram and array reconstruction algorithm were implemented on PIC16F1829 microcontroller successfully.By collecting and analyzing the current,voltage,and temperature of photovoltaic modules,local reconstruction algorithm be able to identify the shade degree of components and output arrays reconstruction signal based on the recognition results.Shading components can be reconstructed in one row or several rows of arrays according to reconfiguration signal by switch matrix module circuit of power router,which not only increase the output power of arrays but also alleviate the hot spot effect of components.A performance testing platform of power router is built based on 4 row 24 column series parallel photovoltaic array in this paper.The test results show that the power router designed in this paper be able to complete the array reconstruction in time according to different shading modes of the components.After reconstruction,the power of arrays is improved to some extent(by 1%~3%),and the purpose of reducing shading effect on the output power of photovoltaic array is achieved.The power router designed in this paper has the advantages of improving the output power of arrays,simplifying reconstruction algorithm,and alleviating the hot spot effect of components.It is suitable for large-scale array reconfiguration engineering and can also be used in the mismatch reconfiguration of battery packs,So it has a wide range of application prospects.