Search for: voltage-profile
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
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...
A novel multi-area distribution state estimation approach for active networks, Article Energies ; Volume 14, Issue 6 , 2021 ; 19961073 (ISSN) ; Abbaspour Tehrani Fard, A ; Lehtonen, M ; Moeini-Aghtaie, M ; Fotuhi Firuzabad, M ; Sharif University of Technology
MDPI AG 2021
This paper presents a hierarchically distributed algorithm for the execution of distribution state estimation function in active networks equipped with some phasor measurement units. The proposed algorithm employs voltage-based state estimation in rectangular form and is well-designed for large-scale active distribution networks. For this purpose, as the first step, the distribution network is supposed to be divided into some overlapped zones and local state estimations are executed in parallel for extracting operating states of these zones. Then, using coordinators in the feeders and the substation, the estimated local voltage profiles of all zones are coordinated with the local state...
Benefits of demand response on operation of distribution networks: a case study, Article IEEE Systems Journal ; Volume 10, Issue 1 , 2016 , Pages 189-197 ; 19328184 (ISSN) ; Fotuhi Firuzabad, M ; Lehtonen, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc 2016
Despite of the great focus of attention dedicated to demand response (DR), the potential benefits of DR on distribution networks have not yet been quantitatively studied. This paper aims to assess DR potential impacts on major attributes of the operation of a residential distribution network. For doing so, grossly metered usage of more than 1600 residential consumers from Kainuu, Finland, is disaggregated to appliance-level load profiles. The flexibility of the load profiles is also estimated from the survey data and questionnaires. The individual profiles are then adjusted within their flexibility such that the most evenly distributed aggregated load profile is realized. Finally, the...
Optimal DG sizing in primary distribution feeders using dynamic programming approach, Article 2012 11th International Conference on Environment and Electrical Engineering, EEEIC 2012 - Conference Proceedings, 18 May 2012 through 25 May 2012, Venice ; 2012 , Pages 371-375 ; 9781457718281 (ISBN) ; Kenari, M. T ; Mehrasa, M ; Sharif University of Technology
Distributed generation (DG) corresponds to the application of small generating units which are the set up in distribution systems or near load centers. Utilization of DG influences various operational indices of the distribution feeders such as feeder loading, electrical losses and voltage profile. In addition, use of DG in its appropriate size is an essential tool to attain the DG maximum potential advantages. In this paper, an optimization method is proposed to determine the optimal size of DG in the distribution system. This method considers the system technical factors such as losses, voltage profile and loading of the primary distribution system feeders. The optimization process is...
Effects of wind turbines on voltage profile, Article International Aegean Conference on Electrical Machines and Power Electronics, ACEMP 2011 and Electromotion 2011 Joint Conference ; Sept , 2013 , Pages 64-68 ; 9781467350037 (ISBN) ; Ehsan, M ; Afsharirad, H ; Nazaraliloo, M ; Sharif University of Technology
For distribution grids connected wind power generation, voltage quality is an important issue for the system planning purpose. The operation of wind turbines in the distribution networks may affect the voltage quality offered to the consumers. One of the most important considerations is the effect on the voltage profile, i.e. the induced slow voltage variations, which are the subject of this paper. The wind turbines can be operated in two modes: constant-speed and variable-speed. Each one of these cases has different impact on steady state voltage of distribution grids. For evaluation of these impacts, we have simulated SCIG generator that works in constant-speed operation and DFIG generator...
A dynamic fuzzy interactive approach for DG expansion planning, Article International Journal of Electrical Power and Energy Systems ; Volume 43, Issue 1 , 2012 , Pages 1094-1105 ; 01420615 (ISSN) ; Ehsan, M ; Fattahi Meyabadi, A ; Sharif University of Technology
This paper presents a dynamic multi objective model for distribution network expansion, considering the distributed generators (DGs) and network reinforcements. The proposed model simultaneously optimizes three objective functions namely, total cost, emission cost and technical satisfaction (voltage profile) by finding the optimal schemes of timing, sizing, placement and DG technologies in a long term planning period (dynamic planning). The importance of each objective function can be changed in the interactive steps. The calculation algorithm is based on Chaotic Local Search with Modified Honey Bee Mating Optimization (CLSMHBMO). The effectiveness of the proposed model and the calculation...
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) ; Vakilian, M ; Sharif University of Technology
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...
Locating and parameters setting of unified power flow controller for congestion management and improving the voltage profile, Article Asia-Pacific Power and Energy Engineering Conference, APPEEC, 28 March 2010 through 31 March 2010 ; March , 2010 ; 21574839 (ISSN) ; 9781424448135 (ISBN) ; Ehsan, M ; Sharif University of Technology
This paper propose a particle swarm optimization based algorithm for locating Unified power flow controller (UPFC), as well as set its parameters, with static point of view in deregulated electricity markets in order to reduce generation cost, voltage violation and manage congestion. The modeling of UPFC has been adapted based on power injection method. In order to verify and validate the effectiveness of the proposed method, it was applied to 24-bus Reliability Test System (RTS) and the results have been discussed
Multi objective distributed generation planning using a binary particle swarm optimization method, Article 2008 International Conference on Genetic and Evolutionary Methods, GEM 2008, Las Vegas, NV, 14 July 2008 through 17 July 2008 ; 2008 , Pages 140-146 ; 1601320698 (ISBN); 9781601320698 (ISBN) ; Ehsan, M ; Sharif University of Technology
With the introduction of restructuring concepts to traditional power systems, a great deal of attention is given to utilization of distributed generation. Integration of DG units has been known as an alternative for distribution network reinforcement and purchasing energy from transmission network. Considering these facts, in the planning procedure of DG, determination of optimal sizing and sitting is a very important issue. This work presents a comprehensive framework for integration of distributed generations into a distribution network, regarding various technical and economical issues such as reduction of active power losses, environmental pollutions, investment and running costs while...
A heuristic trade off model for integration of distributed generations in deregulated power systems considering technical, economical and environmental issues, Article 2008 IEEE 2nd International Power and Energy Conference, PECon 2008, Johor Baharu, 1 December 2008 through 3 December 2008 ; 2008 , Pages 1275-1279 ; 9781424424054 (ISBN) ; Nasiri, R ; Bagheri, M ; Tehrani, A. A ; Sharif University of Technology
With the introduction of restructuring concepts to traditional power systems, a great deal of attention is given to the utilization of distributed generation. Since the integration of DG units has been known as an alternative for main grid as a resource for energy supply, the determination of optimal sizing and sitting is an important issue in the planning procedure of DG. This work presents a comprehensive multi-objective model for integration of distributed generations into a distribution network, regarding various technical, economical and environmental issues such as reduction of carbon dioxide emissions and investment & running costs while the bus voltages shall be kept within...
Distribution system reliability enhancement using optimal capacitor placement, Article IET Generation, Transmission and Distribution ; Volume 2, Issue 5 , 2008 , Pages 621-631 ; 17518687 (ISSN) ; Fotuhi Firuzabad, M ; Sharif University of Technology
Failure statistics of most utilities indicate that distribution systems make the greatest individual contribution to the unavailability of supply to customers. Optimal capacitor placement in distribution systems has a number of advantages such as reducing losses, improving voltage profile, improving power factor and so on. The conventional objective function of the optimal capacitor placement consists of the total cost of losses and investments. Since capacitors supply reactive loads locally, they improve the load-carrying capability of the lines and therefore play the same role as redundant lines. Thus, optimal capacitor placement can also improve the reliability indices of a distribution...
A combination of MADM and genetic algorithm for optimal DG allocation in power systems, Article 42nd International Universities Power Engineering Conference, UPEC 2007, Brighton, 4 September 2007 through 6 September 2007 ; 2007 , Pages 1031-1035 ; 1905593368 (ISBN); 9781905593361 (ISBN) ; Afsharnia, S ; Khodayar, M. E ; Rahimikian, A ; Sharbafi, M. A ; Sharif University of Technology
Distributed Generation (DG) can help in reducing the cost of electricity to the customer, relieve network congestion, provide environmentally friendly energy close to load centers as well as promote system technical characteristics such as loss reduction, voltage profile enhancement, reserve mitigation and many other factors. Furthermore, its capacity is also scalable and it can provide voltage support at distribution level. The planning studies include penetration level and placement evaluation which are influenced directly by DG type. Most of the previous publications in this field chose one or two preferred parameter as basic objective and implement the optimizations in systems. But due...
Using genetic alghoritm for distributed generation allocation to reduce losses and improve voltage profile, Article 42nd International Universities Power Engineering Conference, UPEC 2007, Brighton, 4 September 2007 through 6 September 2007 ; 2007 , Pages 954-959 ; 1905593368 (ISBN); 9781905593361 (ISBN) ; Sedighizadeh, M ; Bayat, M. R ; Khodayar, M. E ; Sharif University of Technology
This paper presents a method for the optimal allocation of Distributed generation in distribution systems. In this paper, our aim would be optimal distributed generation allocation for voltage profile improvement and loss reduction in distribution network. Genetic Algorithm (GA) was used as the solving tool, which referring two determined aim; the problem is defined and objective function is introduced. Considering to fitness values sensitivity in genetic algorithm process, there is needed to apply load flow for decision-making. Load flow algorithm is combined appropriately with GA, till access to acceptable results of this operation. We used MATPOWER package for load flow algorithm and...
Assessment study of shunt FACTS devices for improving dynamic behavior of induction motors, Article Sixth International Conference on Power Electronics and Drive Systems, PEDS 2005, Kualu Lumpur, 28 November 2005 through 1 December 2005 ; Volume 2 , 2005 , Pages 1352-1355 ; 0780392965 (ISBN); 9780780392960 (ISBN) ; Oraee, H ; Sharif University of Technology
An assessment study of two different shunt FACTS devices for compensating disturbances due to voltage variation in power systems is presented in this paper. Namely, Static Compensator (STATCOM) and Static Var Compensator (SVC) are Considered in this study. Eigen Value analysis and nonlinear time domain simulations for starting motor, motor in load varying state and short circuit on motor terminals show that STATCOM DC Voltage regulation has a better performance Compared to that of SVC. The result that will be presented in the paper will prove the superiorly of STATCOM over SVC in increasing motor speeding up and improving system voltage profile particularly at starting. © 2005 IEEE