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Designing optimal solar water pumping stations for irrigation of agricultural lands

Haase Gundolf, Kirakossian Gagik T., Kirakossyan Gagik H., Mkrtchyan Vazgen A.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2023

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Vol. 32, No. 3

270--283

EN

An investigation into the design of a stand-alone solar water pumping station for supplying rural areas is presented. It includes a study of system components and their modeling. The solar water pumping station comprises a solar panel, DC/DC buck converter, DC motor driving a centrifugal pump, and a reservoir. The fuzzy-based maximum power point tracker is developed to optimize the drive speed and the water discharge rate of the coupled centrifugal pump. These use dN/I, d(dN/dI) use parameters, and a variation of the fill factor∆α as input variables. The proposed solution is based on a judicious fuzzy adjustment of a converter fill factor, which adapts online the load impedance to the solar panel. The simulation results show the effectiveness of the drive system for both transient and steady-state operations. Hence, it is suitable to use this fuzzy logic procedure as a standard optimization algorithm for such solar water pumping stations. The modeling is carried out in MATLAB/Simulink.

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The effect of magnetic field on the efficiency of a silicon solar cell under an intense light concentration

Zoungrana M., Zerbo I., Soro B., Savadogo M., Tiedrebeogo S., Bathiebo D. J.

Advances in Science and Technology. Research Journal

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2017

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Vol. 11, no 2

133--138

EN

This work put in evidence, magnetic field effect the electrical parameters of a silicon solar cell illuminated by an intense light concentration: external load electric power, conversion efficiency, fill factor, external optimal charge load. Due to the high photogeneration of a carrier in intense light illumination mode, in addition of magnetic field, we took into account the carrier gradient electric field in the base of the solar cell. Taking into account this electric field and the applied magnetic field in our model led to new analytical expressions of the continuity equation, the photocurrent and the photovoltage. In this work, we used the electric power curves versus junction dynamic velocity (Sj) to determine, according to magnetic field, the maximum electric power Pelmax and we calculate the solar cell conversion efficiency (η). We also used the J-V characteristics to determine the solar cell short circuit density current (Jcc) and the open circuit voltage (Vco) under magnetic field and we calculate the fill factor (FF). Finally, we used simultaneously the J-V characteristics and equipower curves to determine the optimal external load resistance. The results of this study have showed that the maximum electric power and the conversion efficiency are higher than those of monofacial and bifacial silicon solar cells illuminated by conventional light but they decreased with the increase of magnetic field.

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Photocurrent response of phloxin B-cetyltrimethylammonium bromide photogalvanic cell device

Genwa K. R., Shraddha S.

Materials Science Poland

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2015

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Vol. 33, No. 3

612--619

EN

Photocurrent and photovoltage generation using phloxin B dye in aqueous and micellar medium at different concentrations have been studied in a photogalvanic cell. The photopotential and photocurrent generated were 1135.0 mV and 260.0 μA, respectively. The observed solar energy conversion efficiency with CTAB surfactant was 0.64 % and maximum power of the cell was 66.72 mW. The output of the cell was sensitive to various parameters, like dye concentration, reductant concentration, pH, light intensity, electrode area and diffusion length. Current-potential characteristics studied by I-V curve of the cell and the mechanism of cell photovoltage generation have been presented in the paper.

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Low-cost 320 x 240 uncooled IRFPA using conventional silicon IC process

Ishikawa T., Ueno M., Endo K., Nakaki Y., Hata H., Sone T., Kimata M.

Opto-Electronics Review

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1999

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Vol. 7, No. 4

297-303

EN

A 320 x 240 uncooled infrared focal plane array (IRFPA) with series PN junction diodes fabricated on a silicon-on-insulator (SOI) wafer has been developed. Resistive bolometers, pyroelectric detectors and thermopile detectors have been reported for large scale uncooled IRFPAs, while the detector developed uses the temperature dependence of forward-biased voltage of the diode. The diode has low 1/f noise because it is fabricated on the monocrystalline SOI film which has few defects. The diode is supported by buried silicon dioxide (BOX) film of the SOI wafer, which becomes a part of a thermal isolated structure by using bulk silicon micromachining technique. The detector constains an absorbing membrane with a high fill factor of 90% to achieve high IR absorption, and the readout circuit of the FPA constains a gate modulation integrator to suppress the noise. Low cost IRFPA can be supplied because the whole structure of the FPA is fabricated on commercial SOI wafers using a conventional silicon IC process.