Low-cost post power switch open-circuit fault operation approach for an IPMSM drive

ABSTRACTAluminum is of interest as a constituent for Li battery electrodes due to its low cost and low mass, and because ab initio calculations indicate that solid solution of LiAlO2 with LiMO2 (M = transition metal) in the α-NaFeO2 structure can increase intercalation voltage [1]. In this study, we investigated the effect of Al doping on LiCoO2 and LiMnO2. Single phase LiAlyCo1-yO2 has been synthesized up to y = 0.5 by firing homogenous hydroxide precursors. A systematic increase in the open circuit voltage is observed with Al content. In LiAlyMn1-yO2, the addition of LiAlO2 stabilizes LiMnO2 in the α-NaFeO2 structure under conditions where neither endmember is stable in the structure. High reversible capacity was obtained over both a 4 V and 3 V plateau, indicating that the compound transforms to a spinel-related structure during cycling, but that the cooperative Jahn-Teller distortion is suppressed.

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Impact of Sodium Hexametaphosphate on the Flotation of Ultrafine Magnesite from Dolomite-Rich Desliming Tailings

Minerals ◽

10.3390/min11050499 ◽

2021 ◽

Vol 11 (5) ◽

pp. 499

Author(s):

Duong Huu Hoang ◽

Doreen Ebert ◽

Robert Möckel ◽

Martin Rudolph

Keyword(s):

Ultrafine Particles ◽

Raw Materials ◽

Low Cost ◽

Froth Flotation ◽

Open Circuit ◽

Ore Deposits ◽

Sodium Hexametaphosphate ◽

Low Grade ◽

Low Contrast ◽

The Impact

The depletion of ore deposits, the increasing demand for raw materials, the need to process low-grade, complex and finely disseminated ores, and the reprocessing of tailings are challenges especially for froth flotation separation technologies. Even though they are capable of handling relatively fine grain sizes, the flotation separation of very fine and ultrafine particles faces many problems still. Further, the flotation of low-contrast semi-soluble salt-type minerals with very similar surface properties, many complex interactions between minerals, reagents and dissolved species often result in poor selectivity. This study investigates the flotation beneficiation of ultrafine magnesite rich in dolomite from desliming, currently reported to the tailings. The paper especially focuses on the impact of the depressant sodium hexametaphosphate (SHMP) on the following: (i) the froth properties using dynamic froth analysis (DFA), (ii) the separation between magnesite and dolomite/calcite, and (iii) its effect on the entrainment. As a depressant/dispersant, SHMP has a beneficial impact on the flotation separation between magnesite and dolomite. However, there is a trade-off between grade and recovery, and as well as the dewatering process which needs to be considered. When the SHMP increases from 200 g/t to 700 g/t, the magnesite grade increases from 67% to 77%, while recovery decreases massively, from 80% to 40%. The open circuit with four cleaning stages obtained a concentrate assaying 77.5% magnesite at a recovery of 45.5%. The dolomite content in the concentrate is about 20%, where 80% of dolomite was removed and importantly 98% of the quartz was removed, with only 0.3% of the quartz in the final concentrate. Furthermore, the application of 1-hydroxyethylene-1,1-diphosphonic acid (HEDP) as a more environmentally friendly and low-cost alternative to SHMP is presented and discussed. Using only 350 g/t of HEDP can achieve a similar grade (76.3%), like 700 g/t of SHMP (76.9%), while obtaining a 17% higher magnesite recovery as compared to 700 g/t of SHMP. Interestingly, the proportion of hydrophilic quartz minerals ending up in the concentrate is lower for HEDP, with only 1.9% quartz at a recovery of 21.5% compared to the 2.7% of quartz at a recovery of 24.9% when using SHMP. The paper contributes in general to understanding the complexity of the depressant responses in froth flotation.

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Prediction of Solar Irradiance Based on Artificial Neural Networks

Inventions ◽

10.3390/inventions4030045 ◽

2019 ◽

Vol 4 (3) ◽

pp. 45 ◽

Cited By ~ 4

Author(s):

Waleed I. Hameed ◽

Baha A. Sawadi ◽

Safa J. Al-Kamil ◽

Mohammed S. Al-Radhi ◽

Yasir I. A. Al-Yasir ◽

...

Keyword(s):

Neural Networks ◽

Artificial Neural Networks ◽

Solar Irradiance ◽

Open Circuit Voltage ◽

Low Cost ◽

Short Circuit ◽

Short Circuit Current ◽

Open Circuit ◽

Pv Module ◽

Artificial Neural

Prediction of solar irradiance plays an essential role in many energy systems. The objective of this paper is to present a low-cost solar irradiance meter based on artificial neural networks (ANN). A photovoltaic (PV) mathematical model of 50 watts and 36 cells was used to extract the short-circuit current and the open-circuit voltage of the PV module. The obtained data was used to train the ANN to predict solar irradiance for horizontal surfaces. The strategy was to measure the open-circuit voltage and the short-circuit current of the PV module and then feed it to the ANN as inputs to get the irradiance. The experimental and simulation results showed that the proposed method could be utilized to achieve the value of solar irradiance with acceptable approximation. As a result, this method presents a low-cost instrument that can be used instead of an expensive pyranometer.

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Organic and nano-structured composite photovoltaics: An overview

Journal of Materials Research ◽

10.1557/jmr.2005.0407 ◽

2005 ◽

Vol 20 (12) ◽

pp. 3167-3179 ◽

Cited By ~ 152

Author(s):

Sophie E. Gledhill ◽

Brian Scott ◽

Brian A. Gregg

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Organic Semiconductors ◽

Organic Solar Cells ◽

Organic Materials ◽

Low Cost ◽

Open Circuit ◽

Charge Generation ◽

Dye Sensitized ◽

Excitonic Solar Cells

Organic photovoltaic devices are poised to fill the low-cost, low power niche in the solar cell market. Recently measured efficiencies of solid-state organic cells are nudging 5% while Grätzel’s more established dye-sensitized solar cell technology is more than double this. A fundamental understanding of the excitonic nature of organic materials is an essential backbone for device engineering. Bound electron-hole pairs, “excitons,” are formed in organic semiconductors on photo-absorption. In the organic solar cell, the exciton must diffuse to the donor–accepter interface for simultaneous charge generation and separation. This interface is critical as the concentration of charge carriers is high and recombination here is higher than in the bulk. Nanostructured engineering of the interface has been utilized to maximize organic materials properties, namely to compensate the poor exciton diffusion lengths and lower mobilities. Excitonic solar cells have different limitations on their open-circuit photo-voltages due to these high interfacial charge carrier concentrations, and their behavior cannot be interpreted as if they were conventional solar cells. This article briefly reviews some of the differences between excitonic organic solar cells and conventional inorganic solar cells and highlights some of the technical strategies used in this rapidly progressing field, whose ultimate aim is for organic solar cells to be a commercial reality.

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Battery Management for Small Hydroponic Systems and Cultivation Experiments

International Journal of Manufacturing Materials and Mechanical Engineering ◽

10.4018/ijmmme.2021070102 ◽

2021 ◽

Vol 11 (3) ◽

pp. 21-36

Author(s):

Satoru Yamaguchi ◽

Takuya Motosugi ◽

Yoshihiko Takahashi

Keyword(s):

Open Circuit Voltage ◽

Low Cost ◽

Open Circuit ◽

State Of Charge ◽

Battery Management ◽

Charge Capacity ◽

Hydroponic System ◽

Soc Estimation ◽

Hydroponic Systems ◽

Electronic Load

A small hydroponic system that can use sustainable energy such as solar power has been developed. However, the amount of power generated is not constant, and in the case of unstable weather, enough power cannot be obtained. Therefore, it is necessary to store the generated energy in a battery. In order to design low-cost charging equipment, it is necessary to use a smaller battery and to estimate the remaining charge capacity (state of charge: SOC) accurately. To provide an accurate SOC estimation for such systems, a fusion of CI (current integral) and OCV (open circuit voltage) methods is proposed. When using this method, it is necessary to frequently disconnect the electronic load. In these experiments, the optimum disconnection duration, the effects on plants of frequent battery disconnection, and cutting off of the lighting were investigated.

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A New Low-Cost LoRaWAN Power Switch for Smart Farm Applications

10.1109/smc52423.2021.9659076 ◽

2021 ◽

Author(s):

Jocines D. F. Silveira ◽

Artur F. da S. Veloso ◽

Jose V. dos Reis Junior ◽

Andre C. B. Soares ◽

Ricardo A. L. Rabelo

Keyword(s):

Low Cost ◽

Power Switch

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Improved Piezoelectric Performance of Electrospun PVDF Nanofibers with Conductive Paint Coated Electrode

International Journal of Nanoscience ◽

10.1142/s0219581x1950008x ◽

2019 ◽

Vol 19 (02) ◽

pp. 1950008 ◽

Cited By ~ 1

Author(s):

R. Tamil Selvan ◽

W. A. D. M. Jayathilaka ◽

A. Hilaal ◽

S. Ramakrishna

Keyword(s):

Contact Area ◽

Electrode Material ◽

Polyvinylidene Fluoride ◽

Electrode Materials ◽

Low Cost ◽

Short Circuit ◽

Open Circuit ◽

Energy Output ◽

Piezoelectric Performance ◽

Conductive Paint

Fabrication of Nanogenerators (NGs) using Electrospun polyvinylidene fluoride (PVDF) nanofibers for sensing and energy harvesting applications is a trending research due to its flexibility, biocompatibility, low-cost, etc. Different electrode materials, polymer composites had been proposed to increase the energy output. However, the contact area between the electrode material and nanofiber mat which helps to conduct more piezoelectric charges to the electrode surface are still unexplored especially at nanoscale level. In this paper, authors have proposed the use of low-cost carbon conductive paint to increase the contact area between the electrode and nanofiber mat. The electrode material is coated with conductive paint and the NG was fabricated with that electrode to compare the performances with conventional NG. Piezoelectric performance of the proposed NG has increased substantially as it generates an open circuit voltage [Formula: see text]) of 4.5[Formula: see text]V and short circuit current [Formula: see text]) of 25[Formula: see text]nA, whereas the conventional NG can only produce 1.6 [Formula: see text]) and 1.5[Formula: see text]nA [Formula: see text]). A drop test experiment was conducted, and the device consistency was verified experimentally.

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Charge-Transporting-Layer-Free, Vacuum-Free, All-Inorganic CsPbIBr2 Perovskite Solar Cells Via Dipoles-Adjusted Interface

Nanomaterials ◽

10.3390/nano10071324 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1324

Author(s):

Wentao Zhang ◽

Zeyulin Zhang ◽

Qubo Jiang ◽

Ziming Wei ◽

Yuting Zhang ◽

...

Keyword(s):

High Performance ◽

Low Cost ◽

Perovskite Solar Cells ◽

Open Circuit ◽

Research Field ◽

Carbon Paste ◽

Inorganic Perovskite ◽

Electron Transporting Layer ◽

Hole Transporting ◽

Halide Perovskite

The inorganic perovskite has a better stability than the hybrid halide perovskite, and at the same time it has the potential to achieve an excellent photoelectric performance as the organic-inorganic hybrid halide perovskite. Thus, the pursuit of a low-cost and high-performance inorganic perovskite solar cell (PSC) is becoming the research hot point in the research field of perovskite devices. In setting out to build vacuum-free and carbon-based all-inorganic PSCs with the traits of simple fabrication and low cost, we propose the ones with a simplified vertical structure of FTO/CsPbIBr2/carbon upon interfacial modification with PEI species. In this structure, both the electron-transporting-layer and hole-transporting-layer are abandoned, and the noble metal is also replaced by the carbon paste. At the same time, FTO is modified by PEI, which brings dipoles to decrease the work function of FTO. Through our measurements, the carrier recombination has been partially suppressed, and the performance of champion PSCs has far exceeded the control devices without PEI modification, which yields a power conversion efficiency of 4.9% with an open circuit voltage of 0.9 V and a fill factor of 50.4%. Our work contributes significantly to give an available method to explore charge-transporting-layer-free, low-cost, and high-performance PSCs.

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