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    Switch deployment in distribution networks

    , Article Power Systems ; Issue 9789811070006 , 2018 , Pages 179-233 ; 16121287 (ISSN) Izadi, M ; Farajollahi, M ; Safdarian, A ; Sharif University of Technology
    Springer Verlag  2018
    Abstract
    This chapter presents the optimal switch deployment in distribution systems. First, an explanation regarding different types of switches and their functionality is introduced. Then, a fundamental description of fault management procedure in distribution networks is presented. Thereafter, the mathematical formulation of optimal fault management process is described. Optimal switch deployment problem is formulated in the format of mixed integer programming (MIP). The impact of remote controlled switch (RCS) and manual switch (MS) is scrutinized on the interruption cost once they are installed either individually or simultaneously. The concept of switch malfunctions is explained and the... 

    Reliability Evaluation of Smart Distribution Grids

    , Ph.D. Dissertation Sharif University of Technology Kazemi, Shahram (Author) ; Fotuhi Firouzabad, Mahmoud (Supervisor) ; Lehtonen, Matti (Supervisor)
    Abstract
    The term “Smart Grid” generally refers to a power grid equipped with the advanced technologies dedicated for purposes such as reliability improvement, ease of control and management, integrating of distributed energy resources and electricity market operations. Improving the reliability of electric power delivered to the end users is one of the main targets of employing smart grid technologies. The smart grid investments targeted for reliability improvement can be directed toward the generation, transmission or distribution system level. However, radial operating status, aging infrastructures, poor design and operation practices and high exposure to environmental conditions have caused the... 

    Database Schema Extraction Prevention Through DBMS Error Handling

    , M.Sc. Thesis Sharif University of Technology Naghdi, Sepideh (Author) ; Amini, Morteza (Supervisor)
    Abstract
    Nowadays large volume of sensitive data of organizations are stored in the databases. Thus, databases are attractive to the attackers to execute different types of attacks with different purposes. The useful information that attackers try to achieve in the preliminary steps of the attacks against the databases, is the database structure or schema. One of the popular approach to extract the schema of a database is to analyze the returned error messages from its DBMS. Hence, a solution to prevent schema disclosure via the error messages is customizing and modifying them. To achieve this goal, in this thesis, we propose a framework to handle and customize the error messages automatically and... 

    Impacts of fault diagnosis schemes on distribution system reliability

    , Article IEEE Transactions on Smart Grid ; Vol. 3, issue. 2 , 2012 , p. 720-727 ; ISSN: 19493053 Kazemi, S ; Lehtonen, M ; Fotuhi-Firuzabad, M ; Sharif University of Technology
    Abstract
    Design and development of fault diagnosis schemes (FDS) for electric power distribution systems are major steps in realizing the self-healing function of a smart distribution grid. The application of the FDS in the electric power distribution systems is mainly aimed at precise detecting and locating of the deteriorated components, thereby enhancing the quality and reliability of the electric power delivered to the customers. The impacts of two types of the FDS on distribution system reliability are compared and presented in this paper. The first type is a representative of the FDS which diagnoses the deteriorated components after their failing. However, the second type is a representative of... 

    Impacts of fault diagnosis schemes on distribution system reliability

    , Article IEEE Transactions on Smart Grid ; Volume 3, Issue 2 , February , 2012 , Pages 720-727 ; 19493053 (ISSN) Kazemi, S ; Lehtonen, M ; Fotuhi Firuzabad, M ; Sharif University of Technology
    2012
    Abstract
    Design and development of fault diagnosis schemes (FDS) for electric power distribution systems are major steps in realizing the self-healing function of a smart distribution grid. The application of the FDS in the electric power distribution systems is mainly aimed at precise detecting and locating of the deteriorated components, thereby enhancing the quality and reliability of the electric power delivered to the customers. The impacts of two types of the FDS on distribution system reliability are compared and presented in this paper. The first type is a representative of the FDS which diagnoses the deteriorated components after their failing. However, the second type is a representative of... 

    Simultaneous placement of fault indicator and sectionalizing switch in distribution networks

    , Article IEEE Transactions on Smart Grid ; 2018 ; 19493053 (ISSN) Farajollahi, M ; Fotuhi Firuzabad, M ; Safdarian, A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2018
    Abstract
    Automation systems provide substantial improvement in service reliability through speeding up fault management procedure. However, this is at expense of high investments whose justification needs thorough cost/worth analyses. This paper introduces a mathematical model to optimally place automation system devices within distribution networks. The model establishes a trade-off between service reliability improvements and the relevant costs. Among different automation system devices, fault indicators and remote controlled switches are considered here. Also, the impact of manual switches is regarded since their number and location significantly affect the solution of the placement problem. The... 

    Fault Management in Power Distribution Systems Manual & Remote Switchings Timing and Repair Crew Scheduling

    , M.Sc. Thesis Sharif University of Technology Jalilian, Ali (Author) ; Safdarian, Amir (Supervisor)
    Abstract
    Prompt service restoration following faults has always been a concern to power distribution utilities. In this regard, optimal human resource allocation in post-fault service restoration can speed up field remedial actions which count for significant portion of service interruption duration. This thesis develops a fault management navigator that dispatches crews for field actions in a sequential service restoration until the network is restored to the normal state. The developed navigator effectively coordinates manual and remote switching actions as well as repair actions in the hope of achieving minimum service interruption cost. It tackles a real-time problem, periodically updating the... 

    Optimal placement of protective and controlling devices in electric power distribution systems: a MIP model

    , Article IEEE Access ; Volume 7 , 2019 , Pages 122827-122837 ; 21693536 (ISSN) Izadi, M ; Safdarian, A ; Moeini Aghtaie, M ; Lehtonen, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    This paper presents a mathematical model for simultaneous deployment of protective devices (PDs) and controlling devices (CDs) in distribution networks. The PDs include fuses and reclosers and the CDs are remote controlled switches (RCSs) and manual switches (MSs). The model is to minimize equipment costs as well as sustained and momentary interruption costs. It considers the coordination of fuses and reclosers during temporary faults involving fuse saving and fuse blowing schemes. The model is in mixed integer programming (MIP) fashion which can be effectively solved with available solvers. The performance of the proposed model is verified through applying it to Bus 4 of Roy Billinton test... 

    Optimal placement of protective and controlling devices in electric power distribution systems: A MIP Model

    , Article IEEE Access ; Volume 7 , 2019 , Pages 122827-122837 ; 21693536 (ISSN) Izadi, M ; Safdarian, A ; Moeini Aghtaie, M ; Lehtonen, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    This paper presents a mathematical model for simultaneous deployment of protective devices (PDs) and controlling devices (CDs) in distribution networks. The PDs include fuses and reclosers and the CDs are remote controlled switches (RCSs) and manual switches (MSs). The model is to minimize equipment costs as well as sustained and momentary interruption costs. It considers the coordination of fuses and reclosers during temporary faults involving fuse saving and fuse blowing schemes. The model is in mixed integer programming (MIP) fashion which can be effectively solved with available solvers. The performance of the proposed model is verified through applying it to Bus 4 of Roy Billinton test... 

    Design of an Optimal Multi Agent System for Decentralized Implementation of the Active Distribution Management System's Functions Using State Estimation

    , Ph.D. Dissertation Sharif University of Technology Gholami, Mohammad (Author) ; Abbaspour Tehrani Fard, Ali (Supervisor) ; Moeini Aghtaie, Moein (Co-Supervisor)
    Abstract
    In recent years, due to the increase in distributed generation, the use of renewable energy sources and the emergence of restructuring and energy markets, traditional distribution networks transform to complex and active distribution networks. These issues, along with requirements such as increasing power quality and reliability, have increased the need to provide active distribution management systems and the use of effective network monitoring, control and protection systems. Due to the complexity and expanse of distribution networks, as well as the development of the use of metering elements and remotely controllable elements, one of the important issues in these systems is the... 

    Reliability worth assessment of an automatic loop restoration scheme for urban distribution networks

    , Article IEEE PES Innovative Smart Grid Technologies Conference Europe, ISGT Europe ; 2010 Kazemi, S ; Lehtonen, M ; Fotuhi-Firuzabad, M ; Sharif University of Technology
    Abstract
    Distribution automation (DA) application for fault management in the electricity distribution networks is one of the main potential remedial actions to reduce customers' outage times and hence improve service reliability. As a result, various automation schemes have been developed and introduced in different countries and by different venders. The impacts of implementing a specific automation scheme on reliability indices of a given distribution system can be different from other available automation schemes. For this reason, when comparing the available automation schemes with each other or with the other reliability improvement measures, it is necessary to perform a course of reliability... 

    Reliability worth assessment of an automatic loop restoration scheme for urban distribution networks

    , Article IEEE PES Innovative Smart Grid Technologies Conference Europe, ISGT Europe, 11 October 2010 through 13 October 2010 ; October , 2010 ; 9781424485109 (ISBN) Kazemi, S ; Lehtonen, M ; Fotuhi Firuzabad, M ; Sharif University of Technology
    2010
    Abstract
    Distribution automation (DA) application for fault management in the electricity distribution networks is one of the main potential remedial actions to reduce customers' outage times and hence improve service reliability. As a result, various automation schemes have been developed and introduced in different countries and by different venders. The impacts of implementing a specific automation scheme on reliability indices of a given distribution system can be different from other available automation schemes. For this reason, when comparing the available automation schemes with each other or with the other reliability improvement measures, it is necessary to perform a course of reliability... 

    A comprehensive approach for reliability worth assessment of the automated fault management schemes

    , Article 2010 IEEE PES Transmission and Distribution Conference and Exposition: Smart Solutions for a Changing World, 19 April 2010 through 22 April 2010 ; 2010 ; 9781424465477 (ISBN) Kazemi, S ; Lehtonen, M ; Fotuhi Firuzabad, M ; Sharif University of Technology
    Abstract
    Distribution automation application for fault management in the electricity distribution networks is one of the main potential remedial actions to reduce customers' outage times and hence improve service reliability. For this purpose, various automation schemes have been developed and introduced in different countries and by different venders. However, the challenge for electric utilities, especially in today's competitive electricity market, is to identify and evaluate potential reliability reinforcement schemes. Accordingly, appropriate schemes must be determined and prioritized for implementation. In this context, reliability cost/worth assessment plays an important role. A comprehensive... 

    Modeling and evaluation of power-aware software Rejuvenation in Cloud Systems

    , Article Algorithms ; Volume 11, Issue 10 , 2018 ; 19994893 (ISSN) Fakhrolmobasheri, S ; Ataie, E ; Movaghar, A ; Sharif University of Technology
    MDPI AG  2018
    Abstract
    Long and continuous running of software can cause software aging-induced errors and failures. Cloud data centers suffer from these kinds of failures when Virtual Machine Monitors (VMMs), which control the execution of Virtual Machines (VMs), age. Software rejuvenation is a proactive fault management technique that can prevent the occurrence of future failures by terminating VMMs, cleaning up their internal states, and restarting them. However, the appropriate time and type of VMM rejuvenation can affect performance, availability, and power consumption of a system. In this paper, an analytical model is proposed based on Stochastic Activity Networks for performance evaluation of... 

    Financial risk evaluation of RCS deployment in distribution systems

    , Article IEEE Systems Journal ; 2018 ; 19328184 (ISSN) Izadi, M ; Safdarian, A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2018
    Abstract
    Remote controlled switch deployment in distribution networks is usually justified via comparing the required investment with the expected decrease in interruption costs. Although the investment is known prior to the implementation, the stochastic nature of contingencies imposes significant uncertainty on interruption costs. The uncertainty may impose substantial financial risks on the distribution company. This paper aims at evaluating the financial risk and key affecting parameters. For doing so, a step-by-step method is presented to evaluate the risk. The method captures the stochastic nature of contingencies through a sequential Monte Carlo simulation approach. A mathematical formulation... 

    Simultaneous placement of fault indicator and sectionalizing switch in distribution networks

    , Article IEEE Transactions on Smart Grid ; Volume 10, Issue 2 , 2019 , Pages 2278-2287 ; 19493053 (ISSN) Farajollahi, M ; Fotuhi Firuzabad, M ; Safdarian, A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    Automation systems provide substantial improvement in service reliability through speeding up fault management procedure. However, this is at expense of high investments whose justification needs thorough cost/worth analyses. This paper introduces a mathematical model to optimally place automation system devices within distribution networks. The model establishes a trade-off between service reliability improvements and the relevant costs. Among different automation system devices, fault indicators and remote controlled switches are considered here. Also, the impact of manual switches is regarded since their number and location significantly affect the solution of the placement problem. The... 

    Financial risk evaluation of RCS deployment in distribution systems

    , Article IEEE Systems Journal ; Volume 13, Issue 1 , 2019 , Pages 692-701 ; 19328184 (ISSN) Izadi, M ; Safdarian, A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    Remote controlled switch deployment in distribution networks is usually justified via comparing the required investment with the expected decrease in interruption costs. Although the investment is known prior to the implementation, the stochastic nature of contingencies imposes significant uncertainty on interruption costs. The uncertainty may impose substantial financial risks on the distribution company. This paper aims at evaluating the financial risk and key affecting parameters. For doing so, a step-by-step method is presented to evaluate the risk. The method captures the stochastic nature of contingencies through a sequential Monte Carlo simulation approach. A mathematical formulation...