Study Of Photovoltaic Energy Storage Battery Charging And Control Technology

With the rapid reduction of the fossil energy reserves and the increasingly seriousenvironmental problems, seeking a green sustainable utilization of new energy is imminent.Thus, with the advantage of clean, pollution-free and reusable, the solar energy was the favorof all over the world. Meanwhile, as one of the main form of the solar energy utilization,photovoltaic power generation research has great significance.Firstly, from the perspective of international environment, we expound theenvironmental problems of the energy crisis and the fossil fuel combustion briefly, and thusindicated the necessity of green energy development. Then, through the analysis of thecharacteristics of the solar energy, we discussed the significance of the photovoltaic powergeneration, and concluded the research situations all over the world.We in-deeply discussed independent photovoltaic power generation system, as well asthe system structure and the importance of each part. Then, we analyzed power generationprinciple and Ⅰ-Ⅴ character of the solar cell, and on this basis, we drew the two factorsaffecting output power that is sunlight intensity and ambient temperature. In order to makesolar panels output maximum power, this paper also analyzed several commonly usedmaximum power point tracking method, by comparing their advantages and disadvantagesrespectively, we choose the micro increase of duty cycle as the final selection.Moreover, we analyzed several commonly used DC/DC converters, and selected theSEPIC converter according to system requirements. Meanwhile, the working principle andcharging method of lead-acid batteries were introduced, and by comparing several differentcharging methods operating characteristics, we chose a three-stage method as the chargingstrategy for lead-acid battery.This thesis focused on the converter switching loss problem, aiming at this phenomenon,the system introduced soft-switching technology in SEPIC converter, and the design ofresonance parameters are deduced. Through the combination of theoretical analysis andMATLAB/SIMULINK software simulation, we compared the SEPIC converters whether addsoft-switching converter, then we concluded that the soft-switching technology can improvethe SEPIC converter efficiency. Finally, the important components and the design ofhardware/software were presented in detail, the work of summary and outlook was alsoimplemented.