An Optimal Installation Strategy for Allocating Energy Storage Systems and Probabilistic-Based Distributed Generation in Active Distribution Networks

Sattarpour, Tohid,Tousi, Behrouz The Korean Institute of Electrical and Electronic 2017 Transactions on Electrical and Electronic Material Vol.18 No.6

Recently, owing to increased interest in low-carbon energy supplies, renewable energy sources such as photovoltaics and wind turbines in distribution networks have received considerable attention for generating clean and unlimited energy. The presence of energy storage systems (ESSs) in the promising field of active distribution networks (ADNs) would have direct impact on power system problems such as encountered in probabilistic distributed generation (DG) model studies. Hence, the optimal procedure is offered herein, in which the simultaneous placement of an ESS, photovoltaic-based DG, and wind turbine-based DG in an ADN is taken into account. The main goal of this paper is to maximize the net present value of the loss reduction benefit by considering the price of electricity for each load state. The proposed framework consists of a scenario tree method for covering the existing uncertainties in the distribution network's load demand as well as DG. The collected results verify the considerable effect of concurrent installation of probabilistic DG models and an ESS in defining the optimum site of DG and the ESS and they demonstrate that the optimum operation of an ESS in the ADN is consequently related to the highest value of the loss reduction benefit in long-term planning as well. The results obtained are encouraging.

An Optimal Procedure for Sizing and Siting of DGs and Smart Meters in Active Distribution Networks Considering Loss Reduction

Sattarpour, T.,Nazarpour, D.,Golshannavaz, S.,Siano, P. The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.3

The presence of responsive loads in the promising active distribution networks (ADNs) would definitely affect the power system problems such as distributed generations (DGs) studies. Hence, an optimal procedure is proposed herein which takes into account the simultaneous placement of DGs and smart meters (SMs) in ADNs. SMs are taken into consideration for the sake of successful implementing of demand response programs (DRPs) such as direct load control (DLC) with end-side consumers. Seeking to power loss minimization, the optimization procedure is tackled with genetic algorithm (GA) and tested thoroughly on 69-bus distribution test system. Different scenarios including variations in the number of DG units, adaptive power factor (APF) mode for DGs to support reactive power, and individual or simultaneous placing of DGs and SMs have been established and interrogated in depth. The obtained results certify the considerable effect of DRPs and APF mode in determining the optimal size and site of DGs to be connected in ADN resulting to the lowest value of power losses as well.

An Optimal Procedure for Sizing and Siting of DGs and Smart Meters in Active Distribution Networks Considering Loss Reduction

T. Sattarpour,D. Nazarpour,S. Golshannavaz,P. Siano 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.3

The presence of responsive loads in the promising active distribution networks (ADNs) would definitely affect the power system problems such as distributed generations (DGs) studies. Hence, an optimal procedure is proposed herein which takes into account the simultaneous placement of DGs and smart meters (SMs) in ADNs. SMs are taken into consideration for the sake of successful implementing of demand response programs (DRPs) such as direct load control (DLC) with end-side consumers. Seeking to power loss minimization, the optimization procedure is tackled with genetic algorithm (GA) and tested thoroughly on 69-bus distribution test system. Different scenarios including variations in the number of DG units, adaptive power factor (APF) mode for DGs to support reactive power, and individual or simultaneous placing of DGs and SMs have been established and interrogated in depth. The obtained results certify the considerable effect of DRPs and APF mode in determining the optimal size and site of DGs to be connected in ADN resulting to the lowest value of power losses as well.

An Optimal Installation Strategy for Allocating Energy Storage Systems and Probabilistic-Based Distributed Generation in Active Distribution Networks

Tohid Sattarpour,Behrouz-Tousi 한국전기전자재료학회 2017 Transactions on Electrical and Electronic Material Vol.18 No.6

Recently, owing to increased interest in low-carbon energy supplies, renewable energy sources such as photovoltaics andwind turbines in distribution networks have received considerable attention for generating clean and unlimited energy. The presence of energy storage systems (ESSs) in the promising field of active distribution networks (ADNs) would havedirect impact on power system problems such as encountered in probabilistic distributed generation (DG) model studies. Hence, the optimal procedure is offered herein, in which the simultaneous placement of an ESS, photovoltaic-based DG, andwind turbine-based DG in an ADN is taken into account. The main goal of this paper is to maximize the net present valueof the loss reduction benefit by considering the price of electricity for each load state. The proposed framework consists ofa scenario tree method for covering the existing uncertainties in the distribution network’s load demand as well as DG. Thecollected results verify the considerable effect of concurrent installation of probabilistic DG models and an ESS in definingthe optimum site of DG and the ESS and they demonstrate that the optimum operation of an ESS in the ADN is consequentlyrelated to the highest value of the loss reduction benefit in long-term planning as well. The results obtained are encouraging.

Exploring the Interplay of Planning Time, Reasoning Demands, and Language Learning Aptitude in Iranian EFL Learners’ Written Production

Simin Sattarpour,Farahman Farrokhi 아시아영어교육학회 2017 The Journal of Asia TEFL Vol.14 No.4

First, this investigation – inspired by Robinson’s (2001a, 2001b, 2003, 2011) Cognition Hypothesis and Skehan’s (1998, 2003) Trade-Off Hypothesis – intends to explore how second language writing can improve language learning through manipulating cognitive task complexity dimensions. Second, it attempts to examine if task complexity factors and cognitive learner-related variables have interaction effects on linguistic production. It focuses on planning time and intentional reasoning demands, language learning aptitude, and measures of lexical complexity, syntactic complexity, and accuracy. The participants were 226 intermediate Iranian EFL learners. In a between-subjects design, the participants were first assigned to three experimental groups randomly, each group receiving a task with different level of reasoning demands. Then, within each group, we did a stratified random sampling and assigned an equal number of learners with higher and lower aptitude levels to planned and unplanned groups. The results revealed that (a) planning time availability led to significantly more syntactic complexity, (b) increasing task complexity with regard to reasoning demands resulted in higher gains of lexical and syntactic complexity, whereas no significant effect was detected on accuracy, (c) a significant interaction effect between planning and reasoning demands was found only on accuracy, and (d) a three-way interaction among planning, reasoning demands, and language learning aptitude was observed on accuracy. Generally, the findings are discussed with regard to the predictions of the Cognition Hypothesis and the Trade-Off Hypothesis.

Written Text Quality and Socio-affective Strategy Use: Monolinguals versus Bilinguals across Different Proficiency Levels

Fatemeh Poorebrahim,Simin Sattarpour,Zahra Fakher Ajabshir 아시아테플 2019 The Journal of Asia TEFL Vol.16 No.4

The primary purpose of the current study was to examine the writing performance and the use of socio-cognitive strategies among monolingual Persian and bilingual Turkish-Persian EFL learners across two proficiency levels. A mixed-method approach was employed to analyze the data gathered from the quantitative analysis of socio-affective writing strategy questionnaires as well as qualitative analysis of sample written texts and semi-structured interviews. Results of a series of two-way ANOVAs showed that bilinguals used more positive affective strategies than monolinguals. While the difference between high-proficient and low-proficient participants in strategy use was not significant, some differences were found between bilinguals and monolinguals across different proficiency levels concerning their overall writing quality. The findings also highlighted the underestimation of writing socio-affective strategy instruction, which can be considered as one of the reasons contributing to the writing problems of EFL learners.