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14. Bidirectional Electric Vehicles Service Integration in Smart Power Grid with Renewable Energy Resources

Author

Mohamed, Ahmed A S, Mr and Mohamed, Ahmed A S, Mr

Abstract

As electric vehicles (EVs) become more popular, the utility companies are forced to increase power generations in the grid. However, these EVs are capable of providing power to the grid to deliver different grid ancillary services in a concept known as vehicle-to-grid (V2G) and grid-to-vehicle (G2V), in which the EV can serve as a load or source at the same time. These services can provide more benefits when they are integrated with Photovoltaic (PV) generation. The proper modeling, design and control for the power conversion systems that provide the optimum integration among the EVs, PV generations and grid are investigated in this thesis. The coupling between the PV generation and integration bus is accomplished through a unidirectional converter. Precise dynamic and small-signal models for the grid-connected PV power system are developed and utilized to predict the system’s performance during the different operating conditions. An advanced intelligent maximum power point tracker based on fuzzy logic control is developed and designed using a mix between the analytical model and genetic algorithm optimization. The EV is connected to the integration bus through a bidirectional inductive wireless power transfer system (BIWPTS), which allows the EV to be charged and discharged wirelessly during the long-term parking, transient stops and movement. Accurate analytical and physics-based models for the BIWPTS are developed and utilized to forecast its performance, and novel practical limitations for the active and reactive power-flow during G2V and V2G operations are stated. A comparative and assessment analysis for the different compensation topologies in the symmetrical BIWPTS was performed based on analytical, simulation and experimental data. Also, a magnetic design optimization for the double-D power pad based on finite-element analysis is achieved. The nonlinearities in the BIWPTS due to the magnetic material and the high-frequency components are investigated rely o

Published
2017

19. Synthesis and reactions of 3-hydrazino-2,7,8,9-tetrahydro-1Hbenzo[ 6',7']cyclohepta[1',2':4,5]pyrido[2,3-d]pyrimidin-1-one.

Author

Mohamed Ahmed, Mohamed S. and Farghaly, Thoraya A.

Subjects
*HYDRAZONES, *PHENYLHYDRAZINE, *PYRAZOLES, *RING formation (Chemistry), *HYDRAZINE, *ALDEHYDES, *ACETIC acid, *KETONES, *PYRIMIDINES
Abstract

3-Hydrazino-2,7,8,9-tetrahydro-1H-benzo [6′,7′]cyclohepta[1′,2′:4,5] pyrido[2,3-d] pyrimidin-1-one (5) was prepared in good yield by reaction of 3 or 4 with hydrazine hydrate under reflux. Reaction of compound 5 with different aldehydes in acetic acid gave the corresponding hydrazono derivatives 7. Cyclization of the latter compounds with bromine in acetic acid afforded a series of novel pentacyclic compounds namely, 5,6,7,11-tetrahydro-15H-benzo[ 6″',7″']cyclohepta[1″',2″:4′,5′]pyrido[2′,3′-d][1,2,4] triazolo[4,3-a]pyrimidin-15-ones (11af). In addition, reaction of compound 5 with β-diketones and a-diketone were investigated. The structures of the so formed compounds were confirmed by elemental and spectral analyses (¹H NMR, 13C NMR, IR and MS). [ABSTRACT FROM AUTHOR]

Published
2009

20. Evaluation of the remineralizing effect of the chicken eggshell paste after removal of the fixed orthodontic appliance: An in vitro study.

Author

Fathy Abo-Elmahasen MM, Shaaban AM, Elsaharty M, Mohamed AAS, Assadawy MI, and El Sayed IS

Abstract

Background: Demineralization of the enamel surface, which appears as white spot lesions during and after removal of the fixed orthodontic appliance, is the most common disadvantage of the orthodontic treatment course. Using the remineralizing agents during and after orthodontic treatment helps to avoid those enamel defects., Objective: The present study aims to assess the remineralizing effect of the chicken eggshell powder on the demineralized enamel surfaces after debonding the orthodontic bracket system., Materials and Methods: The current study was performed on 80 prepared premolar crowns embedded into acrylic molds. The samples were prepared to receive routine steps of the bonding process for the bracket system. The paste of the chicken eggshell powder was added to the samples after the debonding process. Scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) were used to evaluate the remineralization effect of the chicken eggshell powder. Also, the Vickers microhardness tester was used to assess the enamel surface microhardness., Results: It was found that the mean value of the Ca/P ratio for the samples before bonding of the orthodontic bracket system was (4.17 ± 2.2). This value significantly decreased to (2 ± 1.3) after debonding of the orthodontic bracket system and then showed a significant increase to (4.79 ± 2.65) after remineralization. These results were assured by the values of the Vickers microhardness tester., Conclusion: The chicken eggshell powder has an excellent remineralization effect for the demineralized enamel surface after debonding the orthodontic enamel surface., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Journal of Orthodontic Science.)

Published
2024
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