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Showing 14 results for Distribution Network
Mr. M. Ostad, Dr. E. Mashhour, Mr. S. H. R. Ale Mohammad,
Volume 1, Issue 3 (3-2013)
Abstract
Reconfiguration of distribution networks means changing network configurations by changing the normally open and normally closed switches in the network with a variety of purposes including loss reduction, load balancing, improve voltage profile, or a combination of these occurs. Reconfiguration takes place on both daily and seasonal time horizon. Most of the studies in this field have been focusing on power loss. Given the importance of energy losses from an economic perspective, this paper presents a method for the reconfiguration season radial distribution networks, with the aim of reducing energy losses can be developed. Due to the current approach of the electricity industry and the expected increase in the presence of distributed generation (DG) in distribution network, distribution network reconfiguration in the presence of DG are study. The propose models solved by using genetic algorithm and its efficient implementation on a 32-bus test network is investigated. The results suggest the importance of choosing the objective function and show its effectiveness.
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Volume 3, Issue 1 (9-2014)
Abstract
Abstract: Evaluation of future distribution networks reliability is an important subject, because the demand for more reliable services which have less outages is increasing. Studies show that 90 percent of customers, outages is related to distribution system, so evaluation and improvement of distribution networks reliability is necessary. In this thesis reliability indices such as load points indices and system indices (consumer and load) are formulated. Then they are solved using self-healing smart grid concept and an algorithm called Encoded markov cut set (EMCS). This algorithm is based on circuit minimal tie set using Petri nets concepts. The most important feature of this algorithm is its comprehension. To achieve the above purposes and carry out the represented algorithm, a computer program is provided in Matlab software and is applied on Roy Billinton distribution Test System (RBTS). Then the reliability indices are calculated and the results of simulation are evaluated. The obtained results show considerable effects on improvement of distribution networks consumer and load indices.
Javad Mehrjooyan, Rahman Ansaripour,
Volume 6, Issue 2 (3-2018)
Abstract
The distribution system establishes the relationship between the transmission system and the consumer and it is the closest part of the power system to the consumer. Due to increasing demand for electricity, environmental constraints and competition in the energy supply market, transmission and distribution systems often operate under heavy load conditions. Severe voltage drops, multiple blackouts and high losses are major problems in distribution networks. Reconfiguration is the simplest and least costly way to meet the above goals relatively. In this study, the Reconfiguration of distribution networks is presented as an optimization problem. An objective function including active power loss indices and voltage profiles is introduced. Various scenarios have been introduced to examine this approach. To solve this problem, the Imperialist Competition Optimization (ICA) algorithm is used in Matlab software environment. Simulation results on IEEE standard radial distribution systems 33, 69 and 118 show that optimizing the opening and closing position of the switches will greatly improve the performance of the distribution system.
Mahdi Taleb, Dr. Bahador Fani, Dr. Ghazanfar Shahgholian,
Volume 9, Issue 2 (8-2020)
Abstract
Renewable sources are used to provide power in power systems on feeders or near consumers. The placement and installation of these resources should take into account their negative effects on the distribution network. In this paper based on flow control of dispersed production resources by using current-voltage-voltage diagrams during the error, a method of regulating the coordination of protective measures is presented. The flows during the error, with the presence and absence of dispersed production resources, have been designated at various locations and compared to each other. The simulation results in ETAP software shown that adjust the coordination of protective equipment in some cases by entering these resources into the network, they get into trouble and the protective coordination is restored using the proposed method.
Fatemeh Eftekhari, Dr. Afshin Lashkar Ara,
Volume 9, Issue 3 (11-2020)
Abstract
Distribution of distribution network and use of D-STATCOM are two conventional methods to reduce losses and improve voltage stability in the distribution network that must be done optimally to bring more benefits to the distribution network. The purpose of this paper is to determine the optimal distribution network arrangement in the presence of D-STATCOM. To solve the problem of rearrangement of the distribution network along with determining the capacity and installation location of D-STATCOM, the propeller algorithm (GOA) along with multi-objective weighted method with the objective of reducing losses and improving voltage stability has been used. The proposed method is simulated on two IEEE standard 33 and 69 bus tests. Three different scenarios were considered for the simulation, which are the presence of D-STATCOM only in the distribution network, rearrangement of the only distribution network and rearrangement of the distribution network with the presence of D-STATCOM and the results of the proposed method will be compared with PSO algorithm.
Mrs. Maryam Faghihi Rezaei, Dr. Majid Gandomkar, Dr. Javad Nikoukar,
Volume 10, Issue 3 (12-2021)
Abstract
In this paper, the protection coordination for Digital dual-setting directional overcurrent relays (DS-DOCR) in the presence of renewable energy sources and energy storage system in the conditions of maximum and minimum fault current in the distribution network is investigated. The proposed scheme minimizes the total operating time of the relays to achieve fast protection coordination in DS-DOCR relays. In addition, to increase the flexibility in the DS-DOCR settings, the permitted range for all relay parameters such as A, B, pickup current (IP), and time dial setting (TDS) is explained in both forward and backward directions. In the proposed scheme, the operating results of DS-DOCR relays on the IEEE 9-bus distribution network in the presence of maximum penetration of photovoltaic sources (PV), wind and energy storage systems (ESSs), in maximum and minimum fault current conditions are investigated. Simulation of the study method is done in DIgSILENT Power Factory software. The numerical results indicate that the proposed solution algorithm has ideally provided the optimal values of the DS-DOCR relays setting parameters, and is capable of achieving reliable and fast protection coordination.
Moaiad Mohseni, Mahmood Joorabian, Afshin Lashkarara,
Volume 10, Issue 4 (3-2022)
Abstract
Charging electric vehicles in the distribution network is one of the most basic solutions for technical and economic management of energy distribution. In many traditional charging methods, the condition of fully charging cars when leaving the parking lot has always been a problem. But in this article, each car is intelligently charged only based on the amount of energy required to travel its daily journeys. In order to implement this smart method, owners of electric vehicles provide information about the number of trips and the length of their route to the parking charge management, and based on the specifications of the vehicles and the initial energy level of their battery when entering the parking lot, the amount The charge required for them is determined. Then, the charging manager plans the charging based on the tariff of energy consumption time, limitation of distribution network transformers, type of charge level selected (normal or fast) so that charging costs are minimized by observing technical and economic constraints. . The result of intelligent car charging in normal and fast charging conditions and in different limitations of the distribution network and in the presence or absence of load response program is compared with each other. YALMIP and MOSEK software have been used to solve the mixed integer linear programming model.
Dr. Koorosh Esmaeili, Dr. Amir Baktash,
Volume 11, Issue 1 (5-2022)
Abstract
Active shunt filters compensate for current harmonics by injecting equal but opposite harmonic compensating current. The active shunt filter acts as a current source that injects the harmonic components produced by the load, but its phase is shifted 180 degrees. In this paper, the performance of a three-phase parallel active filter without the use of a capacitive bank is investigated and the results are evaluated technically and economically. Simulation results have been obtained using Simulink in MATLAB software. The simulation results show that the power factor correction is done without any harmonic resonance and the source is the only active power generator and the reactive power compensator is responsible.
Saeed Siahkolaei, Dr. Mohammad Tabrizian, Hamidreza Shahmirzad,
Volume 11, Issue 4 (3-2023)
Abstract
Today, electric vehicles have been significantly considered due to the lack of air pollution. However, due to the large volume of vehicles in the city, connecting them to the distribution network without a control program may cause congestion in the network lines and substations. Therefore, a bi-level hierarchical method for connecting electric vehicles to the distribution network to coordinate services and performance constraints of the three main elements, namely fleet operator, distribution system operator, and capacity market operator in the presence of vehicle owners and taking into account driving requirements, charging and compaction costs of power lines and transformers are recommended. In this method, first car owners and fleet operators present their charging program to the distribution system operator according to the predicted market prices. In the next step, if this charging program leads to congestion in the lines or substations and power transformers, it is returned to the fleet operators and the shadow price is determined by the capacity market operator based on the congestion status. Then the new charging program is dispatch according to the new market prices. The proposed method is implemented in a sample distribution network and the simulation results show the efficiency of the proposed method.
Dr. Hajar Bagheri Tolabi, Dr. Afshin Lashkar Ara,
Volume 11, Issue 4 (3-2023)
Abstract
The reconfiguration of electric distribution networks is one of the important periodical actions in the operation phase of power networks. By using proper reconfiguration, different aspects of power quality can be improved with the lowest cost. In this article, the reconfiguration is proposed using the combination of fuzzy logic, Symbiotic Organisms Search algorithm and using the multi-objective function to reduce losses, load imbalance and improve the voltage profile. In addition, Spanning Tree Theory has been used to check the radial condition of the distribution system and connecting all the loads after reconfiguration. Considering that the objective functions do not have the same measuring units, a fuzzy system has also been used for homogenizing the objectives. The designed program has been tested on a real test network with 11 feeders and 95 buses. The final result shows the successful performance of the proposed method in providing a new topology for the distribution network with lower losses, more balanced load and better voltage profile for the intended test system.
Vahab Darafshdar, Dr. Mohammad Tabrizian, Hamidreza Shahmirzad,
Volume 12, Issue 2 (9-2023)
Abstract
Existing power grids are inefficient, due to the lack of energy management and the lack of storage, so power plants have to produce more to maintain power quality. But by using network savers, the need to build more power plants is reduced and network stability is improved and many of these inefficiencies will be remedied. By launching this market, consumers are encouraged to optimally manage their consumption, sell power to the grid during peak hours, increase network stability, and compensate grid shortages through the nearest storage network operator due to proximity to the storage. Consumers cause the least transmission line losses. In this paper, using the proposed multi-objective fuzzy multi-objective optimization problem for modeling of energy storage systems (ESS) planning in active distribution networks (ADS) considers the impact of ESS optimization strategy. Finally, the modified IEEE standard 33-bus distribution system will be used to evaluate the feasibility and performance of the proposed model by examining the two hybrid algorithms.
Dr. Iman Chaharmahali, Dr. Mohammad Jafarifar,
Volume 12, Issue 3 (12-2023)
Abstract
To evaluate the reliability of active distribution networks, there is a need to model distributed generation sources, mainly renewable ones. The traditional (common) reliability models are not able to take into account the intermittent and random nature of these energy sources, so the need for a new reliability model is necessary to model the production sources of this type of distribution network. In analytical methods, an analytical model of the network is prepared and the problem is solved mathematically; but with the complexity of the network, solving problems becomes very difficult and practically impossible. Therefore, in terms of the complexity of the structure and the variety of operating modes of active distribution networks, a simulation [Monte Carlo] method has been proposed to evaluate their reliability. In this method, all failure modes of network components are randomly classified and specified. On the other hand, by using the proposed model of reliability of DGs, the nature of randomness of these sources has been accurately considered in the simulation process. The simulation results of a sample active distribution network indicate that, with the introduction of microgrids, the reliability indicators of the network and its loads have improved, but the microgrid has had the greatest impact on the load indicators within the microgrid itself.
Ehsan Akbari,
Volume 13, Issue 1 (5-2024)
Abstract
Harmonic voltage and current, power factor or reactive power, equilibrium state of three-phase system and voltage drop or voltage regulation are important factors of power quality issue in distribution network. Also, these factors cause serious damage to the indicators of the network and its equipment. To solve this issue, these cases should be corrected by different compensators at the level of the distribution network. Therefore, this paper presents the compensation of destructive indicators of linear and non-linear loads using D-STATCOM based on conventional power theory (CPT) in the distribution network. It is worth mentioning that in this paper, two methods of CPT and momentary active and reactive power theory (PQ) are used for D-STATCOM control strategy. Finally, the proposed design is applied on a three-phase system consisting of linear and non-linear loads using PSIM software, and then the capabilities of the proposed design are evaluated.
Seyed Hossein Hassanzadeh Fard, Dr Amin Samanfar, Dr Mehdi Nikzad, Dr Mohsen Rashidi,
Volume 13, Issue 3 (11-2024)
Abstract
Today's distribution networks have made significant progress in terms of dimensions and components and are one of the important pillars of the economy of each country. Governments often look for ways to minimize network damage in critical and fault situations, limiting the scope of faults to maintain maximum service continuity. After a failure occurs, during the restoration period, the operator or network administrator`s right decision, can reduce the dimensions of the failure and prevent further damage. As future networks move towards self-healing, decision-making functions must be empowered so that by maintaining the technical constraints of the network, they can create sustainable emergencies with timely interventions. To do this, the customer damage function factor can be used, which is presented as a number for each type of customer with the unit of $/kWh. So, the feeders can be valued, but due to the probable nature of the cost in outages, this factor is not complete alone. This article uses the customer damage probability function, which is calculated separately for each feeder and can be applied to the entire network. The cost prediction method for the sample feeder with different kinds of load has been simulated, using the Monte Carlo method as well as the UGF method in MATLAB software. The results show despite having the same input and achieving the same results for both methods, the response speed in the UGF method is much higher.
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