Multiobjective Optimization Technique for Mitigating Unbalance and Improving Voltage Considering Higher Penetration of Electric Vehicles and Distributed Generation (original) (raw)
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Leonardo ENERGY is an initiative managed by the European Copper Institute and its European network of eleven offices, dedicated to building information centres to serve designers, engineers, contractors, architects, general managers, teachers and students, who are professionally or otherwise involved with electrical energy. Through various projects, including the award-winning Leonard Power Quality Initiative, over 130 partners from leading academia and industry are involved with Leonardo ENERGY. The website www.leonardoenergy.org delivers a range of virtual libraries on a broad range of electrical energy related topics providing users with regularly updated articles, application notes, briefing papers, reports and interactive training.
2013
Author(s): Miller, Larry; Cibulka, Lloyd; Brown, Merwin; von Meier, Alexandra; Arghandeh, Reza | Abstract: California is striving to achieve 33% renewable penetration by 2020 in accordance with the state’s Renewable Portfolio Standard (RPS). The behavior of renewable resources and electric vehicles in distribution systems is creating constraints on the penetration of these resources into the distribution system. One such constraint is the ability of present-‐‑day voltage management methodologies to maintain proper distribution system voltage profiles in the face of higher penetrations of PV and electric vehicle technologies. This white paper describes the research gaps that have been identified in current Volt/VAR Optimization and Control (VVOC) technologies, the emerging technologies which are becoming available for use in VVOC, and the research gaps which exist and must be overcome in order to realize the full promise of these emerging technologies.
In this study, different effects of EVs (electric vehicles)/PHEVs (plug-in hybrid electric vehicles) with V2G (vehicle-to-grid) connection capability and renewable energy sources used as DGs (distributed generators) on a power distribution network are analyzed. A power distribution network including CPGs (conventional power generators) located in powerhouses, different types of renewable energy sources consisting of PV (photovoltaic), WT (wind turbine) and FC (fuel cell) systems used as DGs, and EVs with V2G connection capability is considered. Limitations of the power distribution network and an objective function including the power production cost, power loss, and voltage profile that are the most significant parameters of a power grid are defined. The objective function is minimized in the four cases that are the grid with CPGs, the grid with CPGs and DGs, the grid with CPGs and EVs, and the grid with CPGs, DGs and EVs. For the first time, theoretical results together with simulation verifications performed in ETAP/MATLAB environments explicitly verify that the lowest electric power production cost and the best voltage profile are obtained by simultaneously utilizing CPGs, renewable energy sources used as DGs and charging/discharging EVs, while the lowest power loss is obtained by utilizing CPGs and DGs in a grid.
arXiv (Cornell University), 2021
With the considerable increase of Distributed Energy Resources (DER), the reliable and cost-effective operation of distribution grids becomes challenging. The efficient operation relies on computationally dependable and tractable optimisation solvers, which may handle: 1) non-linear AC power flow constraints, and 2) timelinking variables and constraints and objectives of DER, over the operational horizon. In this paper, we introduce an application of a high-performance MultiPeriod AC Optimal Power Flow (MPOPF) solver, called "BATTPOWER", to simulate active distribution grids for a near-future scenario. A large-scale Norwegian distribution grid along with a large population of Electric Vehicles (EV) are here taken as the case-study. We suggest and analyse three operational strategies (in terms of control of charge scheduling fleet of EV) for the Distribution System Operator (DSO): (a) uncoordinated/dumb charge scheduling, (b) coordinated charge scheduling with the objective of energy cost-minimisation without operational constraints of the grid, and (c) coordinated charge scheduling with the objective of energy cost-minimisation along with the operational constraints of the grid. The results demonstrate that the uncoordinated charging would lead to: 1) overloading of lines and transformers when the share of EVs is above 20%, and 2) higher operational costs than the proposed control strategies of (b) and (c). In strategy (b) operational line/transformer limits are violated when the populations of EVs are growing above 36%. This implies that current market design must be altered to allow active control of a large proportion of DERs within grid operational limits to achieve cost minimization at system level. To our knowledge, the work presented in this paper is the first ever attempt to do a comprehensive analysis of the impact of EV charging demand on a real Norwegian distribution grid. Moreover, the inference of the analysis says that the Norwegian distribution networks are more prone to congestion problems than the voltage problems for the EV demand which includes a smart charging scheme accounting for grid conditions.
Impacts of green technologies in distribution power network
The International Journal of Advanced Culture Technology, 2015
Green technologies such as renewable energy resources, Electric Vehicles and Plug-in Hybrid Electric Vehicles (EVs/PHEVs), electric locomotives, etc. are continually increasing at the existing power network especially distribution levels, which are Medium Voltage (MV) and Low Voltage (LV). It can be noted that the increasing level of green technologies is driven by the reduction emission policies of carbon dioxide (CO 2). The green technologies can affect the quality of power, and hence its impacts of are analysed. In practical, the environment such as wind, solar irradiation, temperature etc. are uncontrollable, and therefore the output power of renewable energy in that area can be varied. Moreover, the technology of the EVs/PHEVs is still developed in order to improve the performance of supply and driving systems. This means that these developed can cause harmonic distortion as the control system is mostly used power electronics. Therefore, this paper aims to analyse the voltage variation and harmonic distortion in distribution power network in urban area in Europe due to the combination between wind turbine, hydro turbine, photovoltaic (PV) system and EVs/PHEVs. More realistic penetration levels of SSDGs and EVs/PHEVs as forecasted for 2020 is used to analyse. The dynamic load demands are also taken into account. In order to ensure the accurate of simulation results, the practical parameters of distribution system are used and the international standards such as Institute of Electrical and Electronics Engineers (IEEE) standards are also complied. The suggestion solutions are also presented. The MATLAB/Simulink software is chosen as it can support complicate modelling and analysis.
Traditional power systems have a hierarchical vertical structure. This scheme is changing towards a horizontal structure because a large number of Distributed Generation (DG) units are being integrated into power systems at distribution level. Most of DG units are based on renewable energy sources (RES), which have a stochastic behaviour. Thus, it is better to investigate the impacts of DG integration in a probabilistic approach than a deterministic one, in order to help Distribution Network Operators (DNO) to develop strategies for both grid operation and control to keep high system availability and power quality. As wind power technology has reached a great development and it is expected it will be widely introduced in power systems all around the world in a short term , wind generators will be studied with a special focus. Real data from one Danish DNO will help to derive and verify the models.
The Role of Renewable Energy System in Reshaping the Electrical Grid Scenario
IEEE open journal of the Industrial Electronics Society, 2021
Renewable Energy Systems have been in the spotlight of the academic and industrial research for more than two decades, thanks to the development of several fields related to the Electrical Engineering. More recently, with the increasing complexity of the individual renewable energy systems and the interconnection to the grid, the scientific panorama has been witnessing to a convergence of different topics, which span across several IEEE-IES thematic areas: power electronics, electrical machines, smart grids, energy storage, transportation electrification and aerospace. After a brief overview of the renewable energy technologies, this work deals with how the convergence of multiple technologies developed to provide marginal support to the grid has evolved into the foundation of the future utility grid and expanded to transportation sector. It will be shown how the design of a renewable energy system cannot prescind anymore from the electrical grid and from the ancillary services that are requested. Example of convergence are given for a smart transformer application and for a transportation application.
Electric Power Distribution Engineering
Electric Power Distribution Engineering, 2015
CIRED-International Conference on Electricity Distribution-is the leading Forum where the international electricity distribution community meets. CIRED offers a biennial conference & exhibition where developments and best practices in technology and management of the technical side of electricity distribution are presented and reported. CIRED brings together every two years hundreds engineers from all over the world and is a unique meeting point between electric utility managers, users, manufacturers, consultants and research facilities to exchange ideas and share experiences on technological changes.It is the place to become fully aware of new business developments and opportunities in Electricity Distribution. CIRED is also a major exhibition reflecting the advances in the power distribution engineering, the place where decision makers meet and commercial contacts needed for the decade to come are made. CIRED'99 TECHNICAL PROGRAM The CIRED'99 Conference preferred subjects are listed below paying particular attention to dispersed generation and costs reduction. The changing tasks of management in Electricity Distribution where focus is moving from technology to business development are particularly highlighted in session 6.