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    Performance evaluation of energy meters in nonses'usoidal environment based on IEEE 1459 standard

    , Article 22nd International Conference and Exhibition on Electricity Distribution, CIRED 2013; Stockholm; Sweden; 10 June 2013 through 13 June 2013 ; Volume: 2013, Issue: 615 , 2013 ; 9781849197328 (ISBN) Youhannaei, M ; Honarmand, M. E ; Ouni, S ; Mehri, R ; Behinh, Y ; Mokhtari, H ; Talebi, J ; Sharif University of Technology
    The objective of this work is to study the effects of harmonics on energy meters. This study is canied out based on IEEE 1459 standard through extensive tests on some energy meters installed at Gil an utility consumers. First, a review on IEEE 1459 standard on power definitions will be given. The definitions are then ervaluated for a compact Fluorescent Lamp (CFL) as a harmonic generating load. Then, the results of the performance e-alnation of two energy meters are presented for different linear and nonlinear loads based on IEEE1459 standard power definitions. Two different test procedures are performed for this putpose. In the first series of tests, a harmonic polluted voltage is applied... 

    Stability of binary and ternary copper (II) complexes of 2((4-methyl-5-nitro-6-(pyrrolidine-l-yl)pyrimidine-2-yl) amino) propionic acid in aqueous solution

    , Article Scientia Iranica ; Vol. 21, Issue. 6 , 2014 , pp. 2029-2035 ; ISSN: 10263098 Sajadi, S. A. A ; Bagherzadeh, G ; Khaleghian, M ; Kermani, M ; Sharif University of Technology
    The acidity and stability constants of M (MNPPAP) (MNPPAP: 2((4-methyl-5-nitro-6-(pyrrolidine-l-yl)pyrimidine-2-yl)amino)propionic acid) M: Cu2+, Cu (Bpy)2+ (Bpy: 2,2'-Bipyridine), or Cu(Phen) (Phen: 1,10-Phenanthroline) complexes were determined by potentiometric pH titration. It is shown that the stability of the binary Cu (MNPPAP) complex is determined by the basicity of the carboxylate group on one side and amine group on the other side. It is demonstrated that the equilibrium, Cu(Har)2+ (H ar: Heteroaromatic ligand such as Bpy or Phen) + Cu(MNPPAP) ^ Cu(Har)(MNPPAP) + Cu2+, is displacement due to the well known experience that mixed ligand complexes formed by a divalent 3d ion, a... 

    Thermodynamic modeling of the KCl + formamide/glucose/proline + water ternary systems and activity coefficient prediction based on artificial neural network

    , Article Journal of Molecular Liquids ; Volume 207 , 2015 , Pages 136-144 ; 01677322 (ISSN) Ghalami Choobar, B ; Ghalami Choobar, B ; Sharif University of Technology
    Elsevier  2015
    In this research, thermodynamic modeling and activity coefficient prediction of KCl in the (water + formamide/glucose/proline) mixed solvent systems were reported. Thermodynamic study was performed using the potentiometric data based on extended ion interaction Pitzer-Archer model in various mixed solvent systems containing 0, 10, 20, 30 and 40% mass fractions of formamide and glucose at T = 298.2 K and 0, 2.5, 5.0, 7.5 and 10.0% mass fractions of proline at T = 308.2 K and ambient pressure over ionic strength ranging from 0.0014 to 3.9579 mol·kg- 1. The adjustable parameters were determined and the obtained results were then interpreted based on extended ion interaction Pitzer-Archer model.... 

    Multiconverter unified power-quality conditioning system: MC-UPQC

    , Article IEEE Transactions on Power Delivery ; Volume 24, Issue 3 , 2009 , Pages 1679-1686 ; 08858977 (ISSN) Mohammadi, H. R ; Yazdian Varjani, A ; Mokhtari, H ; Sharif University of Technology
    This paper presents a new unified power-quality conditioning system (MC-UPQC), capable of simultaneous compensation for voltage and current in multibus/multifeeder systems. In this configuration, one shunt voltage-source converter (shunt VSC) and two or more series VSCs exist. The system can be applied to adjacent feeders to compensate for supply-voltage and load current imperfections on the main feeder and full compensation of supply-voltage imperfections on the other feeders. In the proposed configuration, all converters are connected back to back on the dc side and share a common dc-link capacitor. Therefore, power can be transferred from one feeder to adjacent feeders to compensate for... 

    Modeling of unified power quality conditioner (UPQC) in distribution systems load flow

    , Article Energy Conversion and Management ; Volume 50, Issue 6 , 2009 , Pages 1578-1585 ; 01968904 (ISSN) Hosseini, M ; Shayanfar, H. A ; Fotuhi Firuzabad, M ; Sharif University of Technology
    This paper presents modeling of unified power quality conditioner (UPQC) in load flow calculations for steady-state voltage compensation. An accurate model for this device is derived to use in load flow calculations. The rating of this device as well as direction of reactive power injection required to compensate voltage to the desired value (1 p.u.) is derived and discussed analytically and mathematically using phasor diagram method. Since performance of the compensator varies when it reaches to its maximum capacity, modeling of UPQC in its maximum rating of reactive power injection is derived. The validity of the proposed model is examined using two standard distribution systems consisting... 

    Reliability worth assessment of an advanced centralized feeder automation scheme

    , Article 2008 IEEE Electrical Power and Energy Conference - Energy Innovation, Vancouver, BC, 6 October 2008 through 7 October 2008 ; 2008 ; 9781424428953 (ISBN) Kazemi, S ; Fotuhi Firuzabad, M ; Lehtonen, M ; Sharif University of Technology
    Feeder Automation (FA) has been recognized by researchers and utilities as one of the attractive remedial measures to enhance service reliability in the electric power distribution systems. Until now, several kinds of FA schemes have been developed for automating of distribution feeders. They can be categorized into three main approaches: semiautomatic, distributed and centralized schemes. The challenge for the utilities, especially in today's competitive electricity market, is to identify and evaluate potential FA schemes and determine that appropriate for implementation. In this context, reliability cost/worth assessment plays an important role. This paper aims to propose a step by step... 

    A simulink study of electric arc furnace power quality improvement by using statcom

    , Article 2008 IEEE International Conference on Industrial Technology, IEEE ICIT 2008, Chengdu, 21 April 2008 through 24 April 2008 ; 2008 ; 9781424417063 (ISBN) Tavakkoli, A ; Ehsan, M ; Batahiee, S. M. T ; Marzband, M ; Sharif University of Technology
    The nonlinear and time varying nature of electric arc furnaces (EAFs) create flicker, harmonics, and voltage/current unbalances. Nowadays to improve the performance of EAFs and the power quality problems of electrical systems around them high speed compensators like STATCOM are needed. This paper uses a time domain model for electric arc furnaces and a new model of STATCOM respectively for creating and improving mentioned power quality problems. In this paper, first we investigate and simulate electric arc furnace and STATCOM using SIMULINK/PSB. Second, we simulate a network including them completely. The proposed models take into account arcing conditions and associated effects improvement... 

    Developing potentiometric sensors for scandium

    , Article Sensors and Actuators B: Chemical ; Volume 348 , 2021 ; 09254005 (ISSN) Dehabadi, M ; Legin, E ; Legin, A ; Yaghmaei, S ; Nechaev, A ; Babain, V ; Kirsanov, D ; Sharif University of Technology
    Elsevier B.V  2021
    Scandium is a rare earth element that is not very abundant on Earth, however in recent years due to the employment of scandium in various high-tech fields the interest in the analytical chemistry of this metal is growing. Currently, the methods for scandium quantification are mainly based on inductively coupled plasma atomic emission and mass-spectrometry and to the best of our knowledge no potentiometric sensors for scandium detection were reported so far. This study is devoted to the development of simple and cost-effective ion-selective sensors for quantification of Sc3+ in aqueous media. Employing the variety of lipophilic ligands suggested in liquid extraction for separation of...