Loading...
Search for:
distributed-generations
0.008 seconds
Total 177 records
A model for stochastic planning of distribution network and autonomous DG units
, Article IEEE Transactions on Industrial Informatics ; Volume 16, Issue 6 , August , 2020 , Pages 3685-3696 ; Farzin, H ; Abbaspour, A ; Fotuhi-Firuzabad, M ; Lehtonen, M ; Sharif University of Technology
IEEE Computer Society
2020
Abstract
This article presents a mixed-integer linear stochastic model for the optimal expansion planning of electricity distribution networks and distributed generation (DG) units. In the proposed framework, autonomous DG units are aggregated and modeled using the well-known energy hub concept. In this model, the uncertainties of heat and electricity demand as well as renewable generation are represented using various scenarios. Although this is a standard technique to capture the uncertainties, it drastically increases the dimensions of this optimization problem and makes it practically intractable. In order to address this issue, a novel iterative method is developed in this article to enhance the...
Reliability based joint distribution network and distributed generation expansion planning
, Article 2020 International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2020, 18 August 2020 through 21 August 2020 ; September , 2020 ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Pourghaderi, N ; Lehtonen, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
In this paper the reliability of distribution network is modeled in joint multistage expansion planning of distribution network assets and distributed generations (DGs). The imposed costs due to network reliability weakness are considerable in the distribution level. Therefore in the proposed model distribution network operator (DNO) considers the costs associated with load interruptions in the planning problem. In this regard, reliability evaluation of the network is modeled in the joint multistage distribution network expansion planning (MDNEP) problem in an integrated manner while the network topology is unknown until the planning problem is not solved. In the proposed joint MDNEP problem...
Incorporating flexibility requirements into distribution system expansion planning studies based on regulatory policies
, Article International Journal of Electrical Power and Energy Systems ; Volume 118 , 2020 ; Jooshaki, M ; Moeini Aghtaie, M ; Abbaspour, A ; Fotuhi Firuzabad, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Increasing penetration of renewable energy sources with intermittent generation calls for further flexibility requirements for efficient as well as the safe operation of power systems. Considering the significant growth of distributed energy resources in distribution systems, a promising approach to fulfill such requirements is to deploy local flexibility sources at the distribution level. Nonetheless, due to the monopoly nature of electricity distribution business, effective regulations are required to direct distribution companies toward fulfilling such goals. Accordingly, this paper aims at proposing various policies to motivate distribution companies to enhance the flexibility of their...
Multi objective distributed generation planning using NSGA-II
, Article 2008 13th International Power Electronics and Motion Control Conference, EPE-PEMC 2008, Poznan, 1 September 2008 through 3 September 2008 ; 2008 , Pages 1847-1851 ; 9781424417421 (ISBN) ; Yousefi, A ; Soroudi, A ; Ehsan, M ; Sharif University of Technology
2008
Abstract
With the increasing share of distributed generation in electrical energy supply, the proper planning procedure for using these units, has become more vital for power system planners. In this paper, the application of multi-objective optimization techniques for siting, sizing and determination of the proper technology to be used, has been investigated in such a way that, the load demand during the planning horizon is met and the technical and environmental constraints are satisfied. Unlike the traditional optimization methods used in power system optimization, NSGA-II multi-objective optimization algorithm does not consider techno-economical and environmental parameters in the constraints of...
An analytical method to consider DG impacts on distribution system reliability
, Article 2005 IEEE/PES Transmission and DistributionConference and Exhibition - Asia and Pacific, Dalian, 15 August 2005 through 18 August 2005 ; Volume 2005 , 2005 , Pages 1-6 ; 0780391144 (ISBN); 9780780391147 (ISBN) ; Rajabi Ghahnavie, A ; Sharif University of Technology
2005
Abstract
Distributed generation is expected to play an increasing role in emerging power systems. They use different type of resources and technologies to serve energy to power system. DG has positive and negative effects for both the utilities and customers. System and load point reliability indices are normally improved if DG is installed in a distribution network. On the other hand, DG has some specific characteristics which distinguish it from conventional generating units. Therefore, they should not be treated as conventional generating units to perform reliability evaluation. An appropriate model is required to be developed in order to assess impacts of DG on reliability indices. Impacts of DG...
Technical and Economic Aspects of Operating of Distribution Systems in Presence of Distributed Generation Considering the Uncertainties
, M.Sc. Thesis Sharif University of Technology ; Ehsan, Mehdi (Supervisor)
Abstract
As electric energy loss in Iran is around 31 percent and 01 percent of this loss is related to the distribution of electric energy, management and operation of distribution network is of high importance. There are different ways for operating the distribution network while decreasing the loss, such as using capacitors, tap changers, energy storing devices, distributed generations, etc. One of the most common ways is to use Network Reconfiguration. In this thesis, daily reconfiguration of a 03-kV 22-bus distribution network is investigated. The objective function consists of cost of energy loss and improvement of voltage profile. Wind turbines are used as the sources of distributed generation...
Improving the Resiliency of Distribution Grids Owning Different Distributed Generation (DG) Resources by Optimal Switching Device Placement and Microgrids Formation
, M.Sc. Thesis Sharif University of Technology ; Abbaspour Tehrani Fard, Ali (Supervisor)
Abstract
In recent years, climate change due to greenhouse gases caused an increase in frequency and intensity of the natural disasters such as hurricanes, blizzards and floods. Moreover, it is anticipated that such events will increase in the future. As a result, power system decision makers are looking for methods to improve power system resiliency against such natural disasters with low occurrence probability and high impact. In this report, the distribution system resiliency has improved via placing remote control sectionalizing switches and micro grids formation during natural disasters. In this regard, the concept of resiliency and its characteristics along with the effect of remote control...
Gas and Electrcicity Networks Co-Planning in Microgrid Generations
, M.Sc. Thesis Sharif University of Technology ; Fotuhi-Firuzabad, Mahmud (Supervisor) ; Rajabi-Ghahnavieh, Abbas (Co-Advisor)
Abstract
As a long-established approach, the electricity and natural gas networks have been operated and planned independently. Nevertheless, in recent years there has been a significant progress in energy conversion technologies in microgrids, thus making the electricity and gas networks more connected on the costumers’ side and also enabling users to utilize each of the carriers interchangeably. This increasing correlation between the two networks has led us to a new approach called co-planning of electricity and natural gas networks.This thesis aimed to take a closer look at this new approach and tried to study different aspects of it. Based on the concept of useful energy, a new approach has been...
Voltage Regulation in DC Microgrids in Superimposed Frequency Droop Method
, M.Sc. Thesis Sharif University of Technology ; Mokhtari, Hossein (Supervisor)
Abstract
Environmental problems and limitation in fossil fuels have increased the application of renewable energy sources (RES) and distributed generations (DG). Due to the DC nature of most loads and DGs, DC microgrids provide a suitable structure to integrate different kinds of DGs and loads. Undesirable voltage regulation and poor power sharing among the sources in conventional voltage-based control methods are solved by the superimposed droop frequency method. However, the superimposed droop frequency scheme suffers from three major problems which are (i) instability in terms of load variation, (ii) limitation in the system maximum loading which is due to the limitation in the transferred...
Optimal Distributed Generation Allocation Considering Power Qaulity Indices
, M.Sc. Thesis Sharif University of Technology ; Mokhtari, Hossein (Supervisor)
Abstract
The demand for independent power generation has been increased in recent years due to the growing demand in distributed networks, losses and power qaulity in power systems. These losses occur in transmission to distribution networks from the generation sites to the end-user loads which have harmonic losses besides fundamental losses.. The non-linear load makes the harmonics flow in the line and create the harmonic losses. However, in a distributed network with several DGs of different types and with all kinds of variable nature loads, an optimal power balance in the system has to be achieved. This optimal objective, which results in minimal energy losses over a specific period of time,...
Power Quality Enhancement in Distribution Systems using Feeder Reconfiguration and Shunt Passive Filter Switching
, M.Sc. Thesis Sharif University of Technology ; Mokhtari, Hossein (Supervisor)
Abstract
The growing usage of nonlinear loads has resulted in increasing voltage and current harmonic levels in distribution systems. Additionally the faults occurring in the distribution system cause voltage sag at the point of customer supply. These two power quality disturbances impose considerable costs on consumers through disrupting the correct performance of sensitive loads, causing unintended outages and decreasing the devices’ useful lifetime. Besides the aforementioned power quality issues, the electric power loss has a determining role in operational costs. In this thesis, based on feeder reconfiguration and shunt passive filters, a strategy is proposed in order to reduce the average...
Linked Planning of Power Grids and Subsidy Policies on Using Photovoltaic Cells for Residential Electricity Supply
, M.Sc. Thesis Sharif University of Technology ; Ehsan, Mehdi (Supervisor)
Abstract
In recent years, due to restructuring in the electric power industry, distributed generation has become one of the most important subjects and DGs and renewable energy sources have been increasingly expected as a supplement and an alternative to a conventional large scale central power system. their success depends not only on the distribution of the available renewable energy sources in a region but also on the power grids connectable capacity in the area. Photovoltaic system is one of the best RESs for residential electricity supply because it is noiseless and solar power is widely available and households can use it via photovoltaic cells in their homes. There are two major problems...
Financial Risk Management of an Electricity Retailer in the Presence of Intermittent Generation and Demand Response
, M.Sc. Thesis Sharif University of Technology ; Fotuhi Firuzabad, Mahmud (Supervisor)
Abstract
According to uncertainty of retailer's customers electricity load and energy price in day-ahead and real-time markets, different scenarios are faced to an electricity retailer. As a result, due to possibility of different scenarios accurance, profit and financial loss of retailer has uncertainty and significant financial risk is imposed to retailer. Electricity retailers for earning the expected profit, reduction ofpossibility of scenarios with little profit (or much loss) and reduction of their risks, use different sources. bilateral contracts, like forward and call option,local wind turbines, distributed generaion, demand response, like load shift and curtailment can be named. This...
Developing an Efficient Framework for Bidding Strategy of a Technical Virtual Power Plant Considering Network Reliability
, M.Sc. Thesis Sharif University of Technology ; Fotuhi Firuzabad, Mahmud (Supervisor)
Abstract
Virtual power plant (VPP) aggregates the capacity of many diverse distributed energy resources (DERs); it creates a single operating profile from a composite of the parameters characterizing each DER and can incorporate the impact of the network on aggregated DER output. In modern power systems, technical virtual power plants (TVPPs) play an important role enabling presence of DERs in electricity markets. This thesis addresses the optimal bidding strategy problem of a TVPP that participates in the day-ahead (DA) electricity market. TVPP schedules its energy resources in a manner that maximize its profit in DA market. Hence, the optimal schedule of its resources is achieved. In a proposed...
Scheduling of Retailers Performance in Electrical Energy Markets with Energy Production;Sell in Pool Market; and Demand Response Policies
, M.Sc. Thesis Sharif University of Technology ; Ehsan, Mehdy (Supervisor)
Abstract
Recent years of capitalism bold role and the competitive environment of variant fields of our life, sparking the idea which considers the electricity (one of the most crucial human requirement) as a commodity of a competitive market to be traded between confident subscribers by easy access. Therefore, by converting the exclusive structure of electricity supply system to a competitive one, some new roles are created to fulfill the electricity generation, transmission and distribution processes. Retail is one of the new roles, defined as a power system restructuring development helper by support of electricity trading, which can be involved in different transactions according to the market...
Designing a Reward-Penalty Scheme to Improve Technical Performance of Distribution System Employing Distributed Generation (DG) Resources
, M.Sc. Thesis Sharif University of Technology ; Abbaspour Tehranifard, Ali (Supervisor) ; Fotuhi Firuzabad, Mahmud (Supervisor)
Abstract
Reward-penalty schemes are known as the most effective tools to regulate the service quality. This thesis tries to design a comprehensive reward-penalty scheme to properly motivate electricity distribution companies (DisCos) to improve the reliability and reduce the energy losses in their networks using Distributed Generation (DG) Resources. So, as the first step, the designing methods of reward-penalty scheme (RPS) and their advantage and disadvantages are introduced, and also a method based on concept of the Yaredestic theory is proposed. The proposed method uses the Fuzzy clustering and is able to set the parameters of RPS in a fair and efficient way. The proposed RPS is implemented on...
Distribution Expansion Planning Considering Energy Storage and Demand Response
, M.Sc. Thesis Sharif University of Technology ; Ehsan, Mahdi (Supervisor)
Abstract
Electricity is one of the most important kinds of energy and also one of essential needs of humans for maintaining their life. Due to growth of costumer’s load and In order for delivering high reliable power to the consumers, the structure of the power grid must be expanded and/or demand side management policies like demand response programs must be taken into consideration. One of the most important and less-focused aspects of power grid expansion planning is, distribution system expansion planning. Distribution system expansion planning (DSEP) is an important task of electric distribution companies and operators in order to appropriately supply their customers load with the minimum cost...
Analysis and Improvement of Grid Voltage Quality Issues in Presence of High PV Penetration
, M.Sc. Thesis Sharif University of Technology ; Parniani, Mostafa (Supervisor)
Abstract
Nowadays, concerns about the reduction of fossil fuels and environmental issues, have made renewable resources more important. Among these resources, photovoltaic (PV) systems are more popular than others, due to their environmental compatibility and unlimited availability of sunlight. Increasing the penetration level of PV systems in electricity networks presents various technical and control challenges such as voltage and frequency variations; and protection and harmonics issues. In this thesis, voltage rise problem due to reverse power flow in distribution feeders is discussed. This is one of the main obstacles to the expansion of these resources in distribution networks.Various solutions...
Expansion Planning of Active Distribution Networks in the Gradual PV
Increase
,
M.Sc. Thesis
Sharif University of Technology
;
Ehsan, Mehdi
(Supervisor)
Abstract
Due to the increasing influence of distribution generation , their effect in planning can't be ignord , especially solar panels ,which are incresing rapidly. The main purpose of this thesis is to an active distribution network that annually load bus and the amount of photovoltaic production in it increases and plan dynamically. In the planning that is done , uncertanty in the amount comsumption load and uncertanty in the pattern of sunlight and also annual innterest rates in the classical system we have planned by optimizing the network expansion costs , in addition to supplying the load bus, we can keep the voltage drop bus and line filling within the allowable . To do this , we considered...
Geometric-Based Fault Diagnosis in a Grid-Connected Inverter
, Ph.D. Dissertation Sharif University of Technology ; Namvar, Mehrzad (Supervisor)
Abstract
Inverters are the main utility in transmitting power from distributed generation (DG) systems toward grid and their safe and immune performance has become a major concern among the system designers. In addition to poor power transmittance, faults in inverter can harm other equipment such as DG and local load. Consequently different protections has been considered to increase the reliability of these systems. Some of these protections like fuses and varistors are implemented in the hardware while others are considered in the processor. In the later class of protections, fault detection and isolation (FDI) system has been the subject of intense investigation in inverters over the past two...