Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Article Citation - WoS: 100Citation - Scopus: 138Transformation of Microgrid to Virtual Power Plant – A Comprehensive Review(Inst Engineering Technology-IET, 2019-02-28) Yavuz, Levent; Onen, Ahmet; Muyeen, S. M.; Kamwa, InnocentTo provide continuity of balancing demand and generation, renewable sources will be more active than today in near future due to the tendency of massive investment on renewable energy sources (RESs) by countries. However, due to the uncertain and intermittent nature of RESs, RESs would create problems on power system operations such as power quality, efficiency, stability and reliability. Owing to having problems with RESs integration, virtual power plant (VPP) has introduced to make this integration smooth without compromising the grid stability and reliability along with offering many other techno-economic benefits. This study reviews structures, types, architecture and operations of VPP along with the status of present implementations worldwide. The types of VPP are introduced in details with the optimisation algorithm used with each type. In addition, VPP is linked with the most of the components in power systems such as distributed generation, active prosumers, transmission system operator and distribution system operator, grid services such as fault ride through, reactive power control as well as with the help of technology such as communications, control and optimisations. This study gives a comprehensive outline of transforming microgrid to VPP that is useful for researchers, consumers, prosumers and utility operators.Conference Object Citation - WoS: 16Citation - Scopus: 23Provision of Ancillary Services by a Smart Microgrid: An OPF Approach(Institute of Electrical and Electronics Engineers Inc., 2018-09) Martinez-Ramos, J. L.; Marcolini, Alejandro Marano; García-López, Francisco De Paula; Almagro-Yravedra, Fernando; Onen, Ahmet; Yoldaş, Yeliz; Fragale, Nunziatina; Marano-Marcolini, AlejandroAncillary services are all services required by the transmission (TSO) or distribution system operator (DSO) to maintain the integrity and stability of the transmission or distribution system as well as the power quality. Ancillary services that can be provided by a microgrid in grid-connected operation are frequency control support, voltage control support, congestion management, reduction of grid losses, and improvement of power quality. This paper presents the optimization problems used in the 3DMicroGrid project to determine the set-points of the different resources present in the microgrid to provide ancillary services to the power system in grid-connected operation: Frequency control, voltage control and load curtailment. Results of the optimization of the pilot microgrid used in 3DMicroGrid are presented. © 2018 Elsevier B.V., All rights reserved.Conference Object Citation - Scopus: 2Machine Learning Algorithms Against Hacking Attack and Detection Success Comparison(Institute of Electrical and Electronics Engineers Inc., 2020-09-15) Yavuz, Levent; Soran, Ahmet; Onen, Ahmet; Muyeen, S. M.Power system protection units has got enormous importance with the growing risk of cyber-attacks. To create sustainable and well protected system, power system data must be healthy. For that purpose, many machine learning applications have been developed and used for bad data detection. However, each method has got different detection and application process. Methods has superiority over other methods. Although, an algorithm can detect some injections easily, same algorithm can be fail when injection type changed. So methods have got different success results when the injection types changed. For that reason, different injection types are applied on power system IEEE 14 bus system via created special hacking algorithm. PSCAD and python linkage has been used for simulation and detection parts. 3 different injection types created and applied on the system and five different most popular algorithms (SVM, k- NN, LDA, NB, LR) tested. Each algorithm's performances are compared and evaluated. © 2020 Elsevier B.V., All rights reserved.Article Citation - WoS: 15Citation - Scopus: 18Local Steady-State and Quasi Steady-State Impact Studies of High Photovoltaic Generation Penetration in Power Distribution Circuits(Pergamon-Elsevier Science Ltd, 2015-03) Jung, Jaesung; Onen, Ahmet; Russell, Kevin; Broadwater, Robert P.Both steady-state and quasi steady-state impact studies in high Photovoltaic (PV) penetration distribution circuits are presented. The steady-state analysis evaluates impacts on the distribution circuit by comparing conditions before and after extreme changes in PV generation at three extreme circuit conditions, maximum load, maximum PV generation, and when the difference between the PV generation and the circuit load is a maximum. The quasi steady-state study consists of a series of steady-state impact studies performed at evenly spaced time Points for evaluating the spectrum of impacts between the extreme impacts. Results addressing the impacts of cloud cover and various power factor control strategies are presented. PV penetration levels are limited and depend upon PV generation control strategies. The steady state and quasi steady-state impact studies provide information that is helpful in evaluating the effect of PV generation on distribution circuits, including circuit problems that result from the PV generation. Published by Elsevier Ltd.Conference Object Citation - Scopus: 1Is the Smart Grid a Good Investment(Institute of Electrical and Electronics Engineers Inc., 2015-04) Onen, Ahmet; Broadwater, Robert P.Electric distribution design and operational goals include meeting customer reliability requirements at the lowest cost. Smart Grid investments have the potential for helping meet these goals, and this paper presents a series of analyses that evaluate the incremental economic benefits of smart grid automation investments. Smart Grid investments provide a number of benefits to customers. Here only benefits that can be objectively quantified in terms of economic savings are considered. Smart Grid automation investments in this work include investments in feeder efficiency, automated switches, and coordinated control of capacitor banks, voltage regulators and load tab changers. Benefits that come from these investments are improved efficiency, reduced demand, shortened storm restoration time, and improved performance during reconfiguration events. The analyses used in the evaluation are very detailed, involving hourly, quasi-steady state power flow analysis over a ten year period for calculating energy consumption and costs, and Monte Carlo simulations for six different storm types. The evaluation shows that similar to other industries, an investment in automation can be justified in terms of hard dollars. © 2017 Elsevier B.V., All rights reserved.Article Citation - WoS: 3Citation - Scopus: 3Investigation of Distributed Series Reactors in Power System Applications and Its Economic Implementation(Wiley, 2016-08-18) Onen, AhmetThe transmission system expansion planning process requires lots of calculations looking many years into the future, and the results are based on assumed load growth. If the load growth assumed in the planning process is not correct and unexpected load growth occurs for some load points, the transmission system could face serious congestion and even overloading problems. In this paper, transmission line impedance adjustment techniques using distributed series reactance (DSR) is considered. The DSRs can be used to control power flow and alleviate overloading problems. A new term, DSR congestion relief factor, is introduced. The DSR congestion relief factor measures the increase of transmission line capacity with the application of DSRs. Parametric studies run on the IEEE 39-bus system are presented. These studies investigate the economic benefits of DSRs and the use of DSRs for single contingencies and compare DSRs with existing technologies for expanding the transmission system.Article Citation - WoS: 12Citation - Scopus: 13Implementation of Cost Benefit Analysis of Vehicle to Grid Coupled Real Micro-Grid by Considering Battery Energy Wear: Practical Study Case(Sage Publications Ltd, 2020-10-07) Koubaa, Rayhane; Yoldas, Yeliz; Goren, Selcuk; Krichen, Lotfi; Onen, AhmetThe proposed research represents a spin-off of the Malta College of Arts, Science and Technology (MCAST) Micro-Grid (MG) project. Particularly, economic impact of Electric Vehicles (EV) integration into the MG is investigated in this paper. The MCAST MG consists of photovoltaic generation unit, a diesel generator and a battery storage system. In this paper, a Vehicle-to grid (V2G) concept is considered where utilities can profit from controlled energy trading operations according to EVs availability. EVs are categorized under different profiles considering energy and time availability of owners typical work hours. V2G energy cost is estimated based on battery energy wear due V2G extra cycling and refunded to EVs owners. As most of developed V2G studies don't consider real world input data or/and EV battery aging cost in system modeling and evaluation, the present paper presents a reliable study as it considers a real life MG with in field measurement input data and appropriate battery degradation model. The adopted model represents a linear approximation with a minimum error value to make a suitable tradeoff of computational complexity and accuracy of obtained results. Economic assessment of the system according to the proposed energy management is performed, where results indicate that the V2G system assisted the MG operation during high electricity price period and achieved economic profit to EVs owners. According to numerical results, V2G energy trading achieved 29.90 EUR of gross selling revenues with only 4.46 EUR as battery degradation cost which makes a 16.41% average cost reduction of daily MG operation cost.Article Implementation of Capital Deferral Algorithm in Real Distribution Systems Considering Reliability by Managing Major Faults(Springer, 2019-10-15) Yoldas, Yeliz; Onen, Ahmet; Broadwater, Robert; Alan, IrfanDistribution automation technology plays a key role on power system reliability by providing faster detection, isolating the faulted area and restoring the fault. In this paper, the impacts of distribution automation are considered on radial distribution system in the event of substation transformer bank malfunction at maximum load level with the aim of deferring the big capital investments. The aim of the proposed method is not only to increase physical impact such as the reliability but also to monetize physical measures into significant economic benefits by deferring the overall investment costs. The proposed algorithm is tested with the real distribution system data, and it is shown that it can obtain remarkable economic benefits by deferring the larger capital equipment investments by making smaller investments in distribution automation.Article Citation - WoS: 376Citation - Scopus: 481Enhancing Smart Grid With Microgrids: Challenges and Opportunities(Pergamon-Elsevier Science Ltd, 2017-05) Yoldas, Yeliz; Onen, Ahmet; Muyeen, S. M.; Vasilakos, Athanasios V.; Alan, IrfanThe modern electric power systems are going through a revolutionary change because of increasing demand of electric power worldwide, developing political pressure and public awareness of reducing carbon emission, incorporating large scale renewable power penetration, and blending information and communication technologies with power system operation. These issues initiated in establishing microgrid concept which has gone through major development and changes in last decade, and recently got a boost in its growth after being blessed by smart grid technologies. The objective of this paper is to presents a detailed technical overview of microgrid and smart grid in light of present development and future trend. First, it discusses microgrid architecture and functions. Then, smart features are added to the microgrid to demonstrate the recent architecture of smart grid. Finally, existing technical challenges, communication features, policies and regulation, etc. are discussed from where the future smart grid architecture can be visualized.Conference Object Efficiency and Cost Evaluation of Distribution Systems Based on Multiple Time Points(Institute of Electrical and Electronics Engineers Inc., 2015-07) Onen, AhmetPhase balancing can offer planning engineers a lowcost means of reducing operating costs, improving efficiency in electric power systems. In general, utilities make phase balancing based on peak load by thinking that is the worst case scenario, but every time is not the case. In this paper, time varying phase balancing algorithm is proposed to investigate the effect of hourly phase balancing for all year (8760 hour for a year) and also evaluate system efficiency and cost saving for all hours. Additionally, it is important for the planning engineers to estimate losses accurately to make phase moves, and the peak load does not always provide the most efficient phase moves among the hours in year. In this paper, there different scenarios will be compared; base case, phase balancing based on peak load, and hourly time varying phase balancing. These scenarios will be compared based on loss reduction, and cost saving with Locational Marginal Price (LMP) to provide the planning engineers ideas about effective power system planning. © 2017 Elsevier B.V., All rights reserved.