الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
With the depletion of fossil fuel resources and increase its prices as well as its high bad side effect on environment, all world marks the renewable energy resources as a green energy replacement. The PV systems become the most popular energy resource in warm states. Precise sizing of PV systems either for grid connected or stand-alone becomes essential to minimize system cost and increase its life time. A new optimum sizing technique for stand-alone PV systems by equating the deficiency and surplus power of the PV to satisfy the load each quarter of hour per day using is proposed. The actual characteristic of daily PV power curve of the solar panels is practically obtained in lab. The minimum size of batteries that can be charged during the surplus power periods and discharged to feed loads for the deficiency periods are designed. In addition, the required PV modules and the corresponding required batteries for night load periods are designed. The proposed PV modules are connected in parallel to avoid the partial shadow problems and also the batteries are connected in parallel to avoid under voltage. On the other hand, self-equalizing system is proposed. The system which consist of a diode grid connected with batteries to prevent the circulating current and regulate the charging-discharging process. Simulation of the system is represented to indicate the effectiveness of the proposed connections which will lead to increase the system efficiency and increase components lifetime. A solution for the great challenge faces PV systems in producing considerable voltage suites the stand-alone and grid connected systems is introduced. Reliable DC/DC converter is proposed with high output voltage ratio, simple design, easy control, compact, low cost and high efficiency. The proposed converter is designed to raise the PV and batteries output voltage to the required load voltage with high current. The design depends on using of multiple of stages include separate coils operated in parallel at charging state then reconfigured to series at discharging to feed the load. This strategy leads to reduce the stress of current on coils and switches. A mathematical model and design criteria have been derived and developed. A MATLAB package is utilized to simulate the converter and prototype for the developed device with 24/400 Voltage have been created. To verify the effectiveness of the proposed converter, number of scenarios and comparisons have been applied with different loading conditions and output voltages taking the effect of coils resistances into considerations. The system proves high performance and efficiency.