الفهرس 
Types of Pumps and Irrigation SystemsOnly 14 pages are availabe for public view
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Abstract
Artificial irrigation became an environmentally critical application for crop production due to rain scarcity. Using a proper irrigation method is essential to maximize water use efficiency and plant biomass. Nowadays, there is a global trend to use clean sources of energy. For this purpose, we propose a solar-powered irrigation system. This study considers alternative irrigation systems using photovoltaic solar systems to pump water from deep wells for new land reclamation, whereas groundwater is the only source. The main objective is to compare various pumping systems using PV energy under the Western West Al Minya area in Egypt.
Two systems were nominated by considering the annual saving: the conventional irrigation Diesel system and a Photovoltaic battery-free irrigation system. The second system requires isolated pipes so solar radiation does not affect water temperature and avoids damage to plant roots. Direct irrigation using PV systems proved to be the optimum economic solution since it gives minimum costs of $0.015/m3 for 100-120 m well depth, compared with $0.073/m3 from the conventional system. This shows that pumping water by PV array reduces the water irrigation costs by about 80% compared with conventional diesel irrigation systems as discussed in detail in the coming chapters costs provide up to about 80% reduction concerning the conventional system.
This thesis discusses a detailed study of the photovoltaic water pumping system and study economics of each component of the irrigation system in Farafra new reclaimed lands. It is well known that the application of artificial irrigation is necessary for crop production due to rain scarcity in arid and semi-arid zones throughout the world. In Farafra, the only source of water is the groundwater via shallow wells. Nowadays, there is a global trend to use clean sources of energy.
The most economical alternative source of energy for groundwater extraction is to use solar-powered irrigation system. The objective of this study is to compare different pumping systems using PV energy under the conditions of Farafra area. Then a complete modeling and simulation for the whole system was done using the commercial software MATLAB.
The simulation used to study the performance of photovoltaic pumping system under different environmental conditions. This model is designed for the atmospheric conditions of Farafra area in EGYPT and the water use regulations of Reef Masr company.
Photovoltaic irrigation system and Diesel irrigation system are compared to reach the minimum cost of irrigation system. The first system is a conventional irrigation Diesel system. It includes a Diesel generator and submersible pump, Iron precipitation ground tank, and distributing pump. But this system was proved to be high cost because the fuel of Diesel generators is expensive and increasing annually. Moreover, the diesel fuel causes environmental pollution. The second system is a PV irrigation system, which includes PV modules, inverter, and submersible pump, Iron precipitation ground tank ,and distributing pump.
The PV irrigation system proved to be the optimum economic solution, since it gives the minimum costs. The PV system achieved the cost of $0.0004 per cubed meter from well head 50 m depth, compared with $0.0011 per cubed meter from the same depth in the conventional system based on a Diesel generator to drive a submersible pump. It is shown in forth coming chapters that pumping water by PV array costs about 36% of the conventional system.
Discussing various approaches for minimal cost, the PV battery-free model has demonstrated a significant cost reduction reaching 63%, referring to a conventional DGS alternative.
Most of the published works concerning DC to DC converter are based on many assumptions and steady state analysis. The results obtained from analysis gives well-known relations relating input and output voltage and its relations with Duty cycle.
This result obtained from steady state analysis agrees with experimental results up to Duty cycle of about 50%. Higher Duty cycle the previously published analysis gives theoretical results for the ratio of output voltage/Input voltage much higher than the experimental results for Duty cycle higher than 50%. The steady state analysis leads to results that doesn’t agree with simulation results for Duty cycle higher than 50%.
The analysis in this work is based on transient analysis, rather than steady state analysis that based on assumptions and this assumption lead to results that doesn’t agree with either simulation or practical results. The transient analysis given in this work is lengthy and tedious to do however, the results obtained from the transient analysis agrees with simulation and experimental results for Duty cycles higher than 50%. Moreover, this work studies the effect of switching frequency on the relation between output voltage and input voltage.
The previously published work based on steady state analysis didn’t consider the effect on switching frequency on converter performance, they consider fixed switching frequency ranging from 20 kHz to 50 kHz. The analysis given in this work gives same results as that given by steady state analysis for the same frequency range; however, the transient analysis given in this work showed that the ratio of output voltage to input voltage decreases for higher frequencies than 50 kHz.