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    Planning to equip the power distribution networks with automation system

    , Article IEEE Transactions on Power Systems ; Volume 32, Issue 5 , 2017 , Pages 3451-3460 ; 08858950 (ISSN) Heidari, S ; Fotuhi Firuzabad, M ; Lehtonen, M ; Sharif University of Technology
    Abstract
    Implementing automation system in distribution networks needs a huge investment that usually cannot be funded entirely in a short period of time. So distribution companies (DISCOs) should develop long-term plans to equip their network with automation technologies as far as economically justifiable. Aiming to provide a methodology for development such plans, this paper presents a novel multistage planning model for implementing distribution automation system considering all main hardware and software infrastructures. The proposed method optimally determines the type, location, and time in which an equipment or infrastructure must be added to network considering the network capacity expansion... 

    Role of outage management strategy in reliability performance of multi-microgrid distribution systems

    , Article IEEE Transactions on Power Systems ; Volume 33, Issue 3 , May , 2018 , Pages 2359-2369 ; 08858950 (ISSN) Farzin, H ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2018
    Abstract
    This paper develops a general framework for reliability assessment of multi-microgrid (MMG) distribution systems. It also investigates reliability impacts of coordinated outage management strategies in a MMG distribution network. According to the proposed reliability evaluation framework, which is based on sequential Monte Carlo simulation method, distribution system is divided into smaller sections/microgrids based on protection system configuration and operating measures are efficiently simulated considering different operation modes. In order to demonstrate the role of outage management strategy in reliability performance of MMG distribution systems, at first, the required features of an... 

    Optimal DG placement and sizing based on MICP in radial distribution networks

    , Article IEEE Proceedings 2017 Smart Grid Conference, SGC 2017 ; Volume 2018-January , 2018 , Pages 1-6 ; 9781538642795 (ISBN) Mousavi, M ; Ranjbar, A. M ; Safdarian, A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2018
    Abstract
    Electric distribution system is one of the most important parts of power systems owing to delivering electricity to consumers. The major amount of losses in a power system is in distribution level. Optimal distributed generation (DG) placement and sizing have a significant effect on power loss reduction in distribution systems. In this paper, a mixed integer conic programming (MICP) approach is presented to solve the problem of DG placement, sizing, and hourly generation with the aim of reducing power loss and costs in radial distribution systems. The costs include both investment and operational costs of DGs. Hourly load variations are considered in the model. To verify the effectiveness of... 

    Linear formulations for topology-variable-based distribution system reliability assessment considering switching interruptions

    , Article IEEE Transactions on Smart Grid ; Volume 11, Issue 5 , May , 2020 , Pages 4032-4043 Jooshaki, M ; Abbaspour, A ; Fotuhi Firuzabad, M ; Muñoz Delgado, G ; Contreras, J ; Lehtonen, M ; Arroyo, J. M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2020
    Abstract
    Continuity of supply plays a significant role in modern distribution system planning and operational studies. Accordingly, various techniques have been developed for reliability assessment of distribution networks. However, owing to the complexities and restrictions of these methods, many researchers have resorted to several heuristic optimization algorithms for solving reliability-constrained optimization problems. Therefore, solution quality and convergence to global optimality cannot be guaranteed. Aiming to address this issue, two salient mathematical models are introduced in this paper for topology-variable-based reliability evaluation of both radial and radially-operated meshed... 

    A Bi-Level framework for expansion planning in active power distribution networks

    , Article IEEE Transactions on Power Systems ; Volume 37, Issue 4 , 2022 , Pages 2639-2654 ; 08858950 (ISSN) Kabirifar, M ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Pourghaderi, N ; Dehghanian, P ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2022
    Abstract
    This paper presents a new framework for multistage expansion planning in active power distribution networks, in which the distribution system operator (DSO) considers active network management by clearing the local energy market at the distribution level. The proposed model is formulated as a bi-level optimization problem, where the upper level minimizes the net present value of the total costs imposed to DSO associated with the investment and maintenance of the network assets as well as the network operation, while the lower level on clearing the local energy market captures the participation of distributed energy resource (DER) owners and demand aggregators to maximize the social welfare.... 

    Optimal resilience-oriented microgrid formation considering failure probability of distribution feeders

    , Article Electric Power Systems Research ; Volume 209 , 2022 ; 03787796 (ISSN) Jahromi, S. N ; Hajipour, E ; Ehsan, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    After a natural disaster, there is an urgent need to supply critical loads such as hospitals as soon as possible. Microgrid (MG) formation is one of the quickest ways to achieve this goal. However, in MG formation studies, there is a trade-off between maximizing the amount of restored loads and minimizing their risk of interruption due to the following aftershocks. For the former objective, the minimum number of MGs should be formed, whereas, for the latter objective, the maximum number of MGs should be configured. This paper tackles this contradictory situation by considering the failure risk of distribution feeders in its proposed optimization framework. In this paper, at first, a novel... 

    Distribution system efficiency improvement by reconfiguration and capacitor placement using a modified particle swarm optimization algorithm

    , Article EPEC 2010 - IEEE Electrical Power and Energy Conference: "Sustainable Energy for an Intelligent Grid", 25 August 2010 through 27 August 2010 ; August , 2010 ; 9781424481880 (ISBN) Rezaei, P ; Vakilian, M ; Sharif University of Technology
    2010
    Abstract
    Capacitor placement/setting is one of the main means for loss reduction and voltage profile improvement in distribution systems. If capacitor placement is meant, the objective function will be the cost of energy losses besides the capacitors costs in a specified period of time. Here, reconfiguration can be used as a strategy to reform the base configuration of the distribution network in order to place the capacitors more efficiently with lower costs. On the other hand, if capacitors are already available in a network, optimum capacitors setting and network reconfiguration should be performed for power loss minimization. In this paper both power loss minimization and capacitor placement cost... 

    Reconfiguration and Capcitor Placement in Distribution Systems for Loss Reduction and Reliability Enhancement

    , M.Sc. Thesis Sharif University of Technology Rezaei, Pooya (Author) ; Vakilian, Mehdi (Supervisor)
    Abstract
    Capacitor setting and reconfiguration are of main means of loss reduction and voltage profile improvement in distribution system operation. Cooperation between these two strategies can effectively minimize power losses in distribution system automation. Also, from the medium and long term viewpoint, capacitor placement and reconfiguration can be used for loss reduction and reliability enhancement. In this section, the sum of losses cost, capacitor investment cost and reliability cost should be minimized. Regarding the need to solve two non-linear combinatorial optimization problems simultaneously, metaheuristic algorithms are used in this thesis. Specifically, Elitist Genetic Algorithm,... 

    Determination of Maximum and Optimal Penetration Level of Distributed Generation in Distributed Systems

    , M.Sc. Thesis Sharif University of Technology Seydali Seyf Abad, Mohammad (Author) ; Parniani, Mostafa (Supervisor)
    Abstract
    Nowadays, development of renewable electricity generation technologies, the advent of small efficient generators and increasing number of grid-connected consumers, have caused increasing interest in energy production next to the consumers locations. Distributed generation (DG) is often defined as small-scale generators that produce several kilowatts to tens of megawatts of electricity. One primary reason for using DG is its potential to reduce power losses in transmission and distribution networks. Several loss reduction methods such as capacitor placement, network reconfiguration and load management are used in distribution systems. Employing DG results in the highest loss reduction and... 

    Operation of Distribution Systems with High Penetration of Wind Energy

    , M.Sc. Thesis Sharif University of Technology Asgary, Farid (Author) ; Fotuhi-Firuzabad, Mahmoud (Supervisor)
    Abstract
    Power distribution systems have been traditionally operated as passive networks which consume electric power supplied by the transmission grid. Increasing utilization of wind energy in distribution systems, notably wind energy, is changing the way distribution sys-tems are operated. The distribution system operators (DSO) would operate the available wind power for reducing the power purchased from the wholesale market. However, high penetration of wind energy in distribution systems would require advanced operation mod-els and additional flexibility in system to offset the variability and uncertainty associated with wind energy. In addition, wind availability often does not positively... 

    Optimization of Sparse Control Structures in Multivariable Systems

    , Ph.D. Dissertation Sharif University of Technology Babazadeh, Maryam (Author) ; Nobakhti, Amin (Supervisor)
    Abstract
    In this thesis, the optimal control structure selection and design of sparse multi-variable control systems is addressed. A fundamental challenge which frequently emerges in engineering, social, and economic sciences, is the optimal selection of a subset of elements, in order to maximally fulfil a design objective. In practice, it is required to solve this underlying selection problem in conjunction with a non-linear or non-convex optimization which is designed to ensure desired performance. The requirement to solve these two problems simultaneously is what makes it inherently difficult; one which has thus far eluded efforts to develop a systematic means of determining its solution. In spite... 

    An Infrastructure for Data Analysis Extraction in Distributed Systems

    , M.Sc. Thesis Sharif University of Technology Ghashami, Mina (Author) ; Habibi, Jafar (Supervisor) ; Mirian Hosseinabadi, Hassan (Supervisor)
    Abstract
    In distributed systems, a huge amount of data is dispersed among different nodes; centralization of this data is infeasible due to communication and storage costs. In addition, Databases with high dimensional data objects are becoming more prevalent is many areas. When the dimensionality increases, the volume of the space increases so fast that the available data becomes sparse. This sparsity is problematic from many aspects. In order to obtain a statistically sound and reliable result, the amount of data needed to support the result often grows exponentially with the dimensionality. Also organizing and searching data often relies on detecting areas where objects form groups with similar... 

    Cooperation Control of a Set of Robots with Different Expertise to Accomplish a Duty

    , M.Sc. Thesis Sharif University of Technology Mortazi, Ali Asghar (Author) ; Bagheri Shouraki, Saeed (Supervisor)
    Abstract
    In recent years, there have been many efforts for distributing a big and complex duty among some agents in order to do it more simply. Large number of these methods are in area called distributed systems, where several different agents start to work together to do a difficult or complex duty which each of them cannot do it lonely. Combination of distributed systems and artificial intelligence is known as distributed artificial intelligence.
    One of the theories that has received attention recently, is called Embodiment. According this theory, in cooperation of a set of agents for performing particular task, expertise might not be integrated in a centralized controller, rather it gradually... 

    Design a Comprehensive Framework for Distribution System Restoration in the Presence of Distributed Generations and Energy Storage Systems

    , Ph.D. Dissertation Sharif University of Technology Riahinia, Shahin (Author) ; Abbaspour Tehrani Fard, Ali (Supervisor) ; Moeini Aghtaie, Moein (Co-Supervisor)
    Abstract
    This thesis presents a stochastic framework to properly involve the uncertainties associated with demand in distribution system restoration (DSR) problem. The restoration process returns the system back to normal operation after any combination of system components have been lost due to an outage. During restoration, the system operator executes a set of actions that progressively mitigate the outage. These actions aim at minimizing the impact of the outage on the final user without compromising the security and operability of the system. In this framework, dynamic programming (DP) is used to solve DSR problem for a distribution system that accommodates various technologies of DG units and... 

    Approximate Agreement Problems in Distributed Systems

    , M.Sc. Thesis Sharif University of Technology Habibi, Kamal (Author) ; Izadi, Mohammad (Supervisor)
    Abstract
    Approximate Agreement (AA) is one of the most important issues in distributed networks in which non-faulty processes execute a voting algorithm to reach the values that are very close to each other. AA for Partially Connected Networks (PCNs) is very limited because a node may not have a complete view of the whole network which makes it difficult to reach the convergence. This research proposes a convergent Fuzzy algorithm for synchronous distributed networks in the presence of faulty or Byzantine processes. When each node receives a new value from its neighbors,it runs the convergent Fuzzy algorithm. If the received value is not in the expected range of values, the processor can discard the... 

    Designing a Proper Residential Demand Response Program To Improve Distribution System Reliability

    , M.Sc. Thesis Sharif University of Technology Sarajpoor, Nima (Author) ; Fotuhi-Firuzabad, Mahmoud (Supervisor)
    Abstract
    In recent years, the pace of increment in electrical energy consumption is getting faster. Establishing new power-plants to keep a balance between generation and consumption not only has a high investment cost but also is a time consuming procedure. Thus, several studies have focused on the demand side management. Residential consumers possess remarkable portion of total electricity consumption. Accordingly, at first, the appropriate residential demand response program is selected based on presented experimental criteria. In the next step, since the network reliability is an important issue to the operators, the impact of implementation of the demand response program is studied on the... 

    Distribution System Planning Implementing Distributed Generation

    , M.Sc. Thesis Sharif University of Technology Porkar, Siyamak (Author) ; Abbaspour Tehrani Fard, Ali (Supervisor) ; Saadate, Shahrokh (Supervisor)
    Abstract
    In the recent years, there is a worldwide wave of considerable changes in power industries, including the operation of distribution networks. Deregulation, open market, alternative and local energy sources, new energy conversion technologies and other future development of electrical power systems must pursue different goals. Also growth in the demand and change in load patterns may create major bottlenecks in the delivery of electric energy. This would cause distribution system stress.Furthermore, in competitive electricity markets, operators determine the electricity price for specific intervals during a day, taking into account various economical and operational factors. Traditionally, a... 

    Modeling and Simulation of Water Distribution in the Various Layers of Polymer Fuel Cell

    , M.Sc. Thesis Sharif University of Technology Savari, Mohammad Hossein (Author) ; Baghalha, Morteza (Supervisor) ; Khorashe, Farhad (Supervisor)
    Abstract
    Fossil fuel are energy resources in decline. In recent years, fuel cell have become as a source of energy to replace conventional systems .Among the various types of fuel cells, PEMFCs (proton exchange membrane fuel cells) possess a series of highly advantageous features such as a low-operating temperature, sustained operation at high-current density, low weight, compactness, potential for low cost and volume, long stack life, fast start-ups and suitability for discontinuous operation. Water management is one of the most critical and challenging problems. There is a delicate balance between the membrane hydration and avoiding cathode from flooding. Cathode flooding occurs when the water... 

    Distribution Networks Expansion Planning Incorporating Smart Grid Technologies

    , M.Sc. Thesis Sharif University of Technology Heidari, Saeed (Author) ; Fotuhi-Firuzabad, Mahmud (Supervisor)
    Abstract
    Planning of distribution networks is usually accomplished using a cost-based conventional model that minimizes the total cost of construction and reinforcement of substations and feeders. The resulted expansion plan designed by this cost-based model is not necessarily the best choice for an electrical distribution company in the nowadays deregulated structure. This happening is mainly due to the fact that the utility seeks to maximize its profit in this competitive environment. On the other hand, this model does not consider the upcoming new challenges ahead of distribution systems, such as smart grid and automation. This thesis presents a novel profit-based model for multi-stage... 

    Developing a New Framework for Expansion Studies of Energy Storage Systems Considering Reconfiguration Capability of Network

    , M.Sc. Thesis Sharif University of Technology Mehrabi, Mohammad (Author) ; Abbaspour Tehranifard, Ali (Supervisor) ; Moeini, Moein (Supervisor)
    Abstract
    Proliferation of distributed energy resources and the developing of smart grid concepts are of a great importance. This, however, influences the future of power systems and necessitates more studies in order to cope with the changes. In this regard, uncontrollability issues are arised by introducing the renewable energy resources in the power systems. To address this issue, energy storage systems are used to mitigate negative consequences of using renewable energy resources. Accordingly, in this thesis, a new framework for determining the capacity and location of the energy storage systems is proposed. In addition, reconfiguration of distribution network is also concerned in order to...