Download or read book Reactive power grid adequacy studies for distribution grids with high distributed generation written by Markus Kraiczy and published by BoD – Books on Demand. This book was released on 2020-01-01 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nowadays distributed energy resources (DER) can provide certain reactive power flexibility for voltage support in alternating current power systems. Besides local voltage support at the distribution level, the DER can also provide reactive power flexibility at the transmission-distribution (T-D) interface, which can improve the reactive power grid adequacy of the distribution level. The term reactive power grid adequacy describes the compliance level of a distribution grid with a predefined reactive power range at the T-D interface. However, a challenge in grid planning procedures is the consideration of the usually intermittent reactive power flexibility potential by the DER. This study aims to develop practicable grid planning procedures for advanced reactive power management at the T-D interface by making use of controllable reactive power sources at the distribution level, like DER and distributed reactive power compensators. The study is performed for a real German distribution grid section with very high-distributed generation.

Download or read book Voltage Stability Analysis with High Distributed Generation DG Penetration written by Rashid Al-Abri and published by . This book was released on 2012 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interest in Distributed Generation (DG) in power system networks has been growing rapidly. This increase can be explained by factors such as environmental concerns, the restructuring of electricity businesses, and the development of technologies for small-scale power generation. DG units are typically connected so as to work in parallel with the utility grid; however, with the increased penetration level of these units and the advancements in unit's control techniques, there is a great possibility for these units to be operated in an autonomous mode known as a microgrid. Integrating DG units into distribution systems can have an impact on different practices such as voltage profile, power flow, power quality, stability, reliability, and protection. The impact of the DG units on stability problem can be further classified into three issues: voltage stability, angle stability, and frequency stability. As both angle and frequency stability are not often seen in distribution systems, voltage stability is considered to be the most significant in such systems. In fact, the distribution system in its typical design doesn't suffer from any stability problems, given that all its active and reactive supplies are guaranteed through the substation. However, the following facts alter this situation: - With the development of economy, load demands in distribution networks are sharply increasing. Hence, the distribution networks are operating more close to the voltage instability boundaries. - The integration of distributed generation in distribution system introduces possibility of encountering some active/reactive power mismatches resulting in some stability concerns at the distribution level. Motivated by these facts, the target of this thesis is to investigate, analyze and enhance the voltage stability of distribution systems with high penetration of distributed generation. This study is important for the utilities because it can be applied with Connection Impact Assessment (CIA). The study can be added as a complement assessment to study the impacts of the installation of DG units on voltage stability.

Download or read book Conference Proceedings of 2021 International Joint Conference on Energy Electrical and Power Engineering written by Cungang Hu and published by Springer Nature. This book was released on 2022-09-02 with total page 733 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will be a collection of the papers presented in the 2021 International Joint Conference on Energy, Electrical and Power Engineering (CoEEPE’21), covering new and renewable energy, electrical and power engineering. It is expected to report the latest technological developments in the fields developed by academic researchers and industrial practitioners, with a focus on power electronics, energy storage and system control in energy and electrical power systems. The applications and dissemination of these technologies will benefit research society as new research directions are getting more and more inter-disciplinary which require researchers from different research areas to come together and form ideas jointly. It will also benefit the electrical engineering and power industry as we are now experiencing a new wave of industrial revelation, that is, electrification, intelligentization and digitalization of our transport, manufacturing process and way of thinking.

Download or read book Distributed Generation Systems written by Gevork B. Gharehpetian and published by Butterworth-Heinemann. This book was released on 2017-05-19 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt: Distributed Generation Systems: Design, Operation and Grid Integration closes the information gap between recent research on distributed generation and industrial plants, and provides solutions to their practical problems and limitations. It provides a clear picture of operation principles of distributed generation units, not only focusing on the power system perspective but targeting a specific need of the research community. This book is a useful reference for practitioners, featuring worked examples and figures on principal types of distributed generation with an emphasis on real-world examples, simulations, and illustrations. The book uses practical exercises relating to the concepts of operating and integrating DG units to distribution networks, and helps engineers accurately design systems and reduce maintenance costs. Provides examples and datasheets of principal systems and commercial data in MATLAB Presents guidance for accurate system designs and maintenance costs Identifies trouble shooting references for engineers Closes the information gap between recent research on distributed generation and industrial plants

Download or read book Advances in Energy System Optimization written by Valentin Bertsch and published by Springer. This book was released on 2017-03-16 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: The papers presented in this volume address diverse challenges in energy systems, ranging from operational to investment planning problems, from market economics to technical and environmental considerations, from distribution grids to transmission grids and from theoretical considerations to data provision concerns and applied case studies. The International Symposium on Energy System Optimization (ISESO) was held on November 9th and 10th 2015 at the Heidelberg Institute for Theoretical Studies (HITS) and was organized by HITS, Heidelberg University and Karlsruhe Institute of Technology.

Download or read book Optimization of Unbalanced Distribution Grid Operations Using Distributed Energy Resources written by Kshitij I. Girigoudar and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Among the various major components of the electric power system, distribution grids have not received a lot of attention from the research community. Today's distribution grids are experiencing a significant transformation due to an increasing amount of smart electric loads and distributed energy resources (DERs), such as electric vehicles, rooftop solar photovoltaic (PV) systems and energy storage. Growing penetration of DERs increase the power injection variability in distribution grids, leading to power quality issues such as voltage unbalance and voltage variations. The intermittent nature of these DERs and load forecasting errors can also increase uncertainty in distribution grids. Furthermore, DERs are managed by different entities such as distribution utility or third-party aggregators whose objectives are conflicting with each other. This makes it challenging to precisely control DER behavior to optimize grid operations. This work introduces an optimization-based approach to improve power quality in unbalanced distribution grids and effectively exploit the flexibility offered by DERs. DERs such as solar PV systems with power electronic inverters can be employed as a cost-effective solution to provide reactive power support and minimize voltage violations and unbalance. We first develop a three-phase optimal power flow (OPF) formulation to identify DER control actions that improve power quality. A major challenge to efficiently solving the three-phase OPF is computation time. To reduce computational complexity, three linear power flow models which are well suited to analyze voltage unbalance are utilized as part of a successive approximation approach to provide good quality solutions that are AC feasible. The OPF formulation is then extended to examine the impact of uncertainty on distribution grid operations by leveraging a chance-constrained optimization approach. By using this method, we identify a set of DER control actions that can be utilized across a range of highly uncertain scenarios. Finally, the challenges of harnessing the flexibility offered by DERs, which are controlled by different entities in the grid, is addressed. A bilevel optimization approach is proposed to determine the collective DER and load flexibility in the network. Our case studies demonstrate that the resulting aggregate power flexibility range can help reduce burdens on transmission system resources while maintaining acceptable power quality in distribution grids.

Download or read book From Smart Grids to Smart Cities written by Massimo La Scala and published by John Wiley & Sons. This book was released on 2021-04-27 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses different algorithms and applications based on the theory of multiobjective goal attainment optimization. In detail the authors show as the optimal asset of the energy hubs network which (i) meets the loads, (ii) minimizes the energy costs and (iii) assures a robust and reliable operation of the multicarrier energy network can be formalized by a nonlinear constrained multiobjective optimization problem. Since these design objectives conflict with each other, the solution of such the optimal energy flow problem hasn’t got a unique solution and a suitable trade off between the objectives should be identified. A further contribution of the book consists in presenting real-world applications and results of the proposed methodologies developed by the authors in three research projects recently completed and characterized by actual implementation under an overall budget of about 23 million €.

Download or read book Enhancement of Distribution System Resilience Through the Application of Volt Var Regulation Devices written by Magdely Noguera and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Power distribution systems could potentially see high penetration of mixed distributed energy resources. This creates a need for new ways to analyze the electrical systems to assure a more resilient, reliable and strong power system. Nowadays, the typical power grid is designed to generate electricity in a dispatchable, centralized mode. The grid typically does not contain much, if any, energy storage capability. In addition to this, the distribution systems have been characterized as having predictable passive loads, without any generation, and largely fed by radial feeders, which means that the power flow is unidirectional from the distribution substations to the customers. The last decade has seen a significant increase in application of renewable generation resources interconnected to both transmission and distribution systems, and this trend is accelerating. The mixed DERs are stochastics sources and are largely not-dispatchable, resulting in potential for power flow from the distribution levels to transmission grid. The incorporation of microgrids has been proposed, with some initial applications. In addition, loads have evolved into more active forms. All these changes make the control of the power grid more complex and add more functions and requirements to reach an optimal operation between all of the entities that make up the power grid of the future. Maintaining or improving the resilience of a power grid will depend on the control of the assets connected into the grid. These assets can be classified as controllable and noncontrollable. This thesis will focus on adding dynamic reactive power sources at pinch points in the distribution system to improve resilience. The scheme will be tested in a distribution model that is presented as an approximation of a possible electrical grid of the future. A method for sizing the reactive compensators will be presented and tested through simulation looking at different levels of solar penetration. The optimal location and sizing of the DSTATCOMs aligned to the reactive power requirements will be analyzed for different scenarios. At the end, these results will provide data for the evaluation of resilient metrics of these systems. On a different note, the application of PV systems has grown in the last years because of the carbon dioxide reduction needs and the growth of the electrical energy demand. Locations where the power grid is not accessible are the ideal to use this new source of energy, such cases are known as stand-alone system installations since they are not connected to the power grid. However, since the dependency on the daylight solar energy resource; many applications include batteries to provide electricity when the sunlight is not available. Therefore, an assessment of two types of solar cells will be included in this thesis to decide which of them will be more efficient to use for small stand-alone applications.

Download or read book Estimation of Flexibility Potentials in Active Distribution Networks written by Daniel Alfonso Contreras Schneider and published by BoD – Books on Demand. This book was released on 2021-10-15 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: The feasible operation region (FOR) allows capturing the aggregated flexibility potential of DER within radial distribution networks, while respecting the technical restrictions of both plants and grid. This thesis proposes a novel approach to compute the FOR, the Linear Flexibility Aggregation (LFA) method, based on the solution of a sequence of linear OPF. With the objective of reducing the computation time, without compromising the accuracy of the assessed FOR. It is shown that the proposed method provides a considerable reduction in processing time compared to similar methods, e.g. Monte-Carlo simulations or non-linear OPF-based methods.

Download or read book Integration of AC DC Microgrids into Power Grids written by Fazel Mohammadi and published by MDPI. This book was released on 2020-12-02 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: AC/DC Microgrids are a small part of low voltage distribution networks that are located far from power substations, and are interconnected through the point of common coupling to power grids. These systems are important keys for the flexible, techno-economic, and environmental-friendly generation of units for the reliable operation and cost-effective planning of smart electricity grids. Although AC/DC microgrids, with the integration of renewable energy resources and other energy systems, such as power-to-gas, combined heat and power, combined cooling heat and power, power-to-heat, power-to-vehicle, pump and compressed air storage, have several advantages, there are some technical aspects that must be addressed. This Special Issue aims to study the configuration, impacts, and prospects of AC/DC microgrids that enable enhanced solutions for intelligent and optimized electricity systems, energy storage systems, and demand-side management in power grids with an increasing share of distributed energy resources. It includes AC/DC microgrid modeling, simulation, control, operation, protection, dynamics, planning, reliability and security, as well as considering power quality improvement, load forecasting, market operations, energy conversion, cyber/physical security, supervisory and monitoring, diagnostics and prognostics systems.

Download or read book Wind Energy The Facts written by European Wind Energy Association and published by Routledge. This book was released on 2012-05-04 with total page 593 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wind power is often held up as the most accessible and cost-effective route to reducing our reliance on fossil fuels and improving our energy independence, yet knowledge of what it offers is often clouded by myths and misunderstandings, which can hamper its adoption. This new book, the result of an ambitious project coordinated by the European Wind Energy Association, aims to present the facts about wind energy. It includes six sections discussing: technology grid integration economics of wind its industry and markets its environmental impacts the scenarios and targets for wind energy. Contributions are drawn from nine leading research bodies across Europe, and the material is global in its scope. It is therefore an essential resource and reference for those whose work or study demands an in-depth examination of the subject, and for anyone who wants detailed, accurate and up-to-date information on this key energy source.

Download or read book Enhancing the Resilience of the Nation s Electricity System written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2017-10-25 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: Americans' safety, productivity, comfort, and convenience depend on the reliable supply of electric power. The electric power system is a complex "cyber-physical" system composed of a network of millions of components spread out across the continent. These components are owned, operated, and regulated by thousands of different entities. Power system operators work hard to assure safe and reliable service, but large outages occasionally happen. Given the nature of the system, there is simply no way that outages can be completely avoided, no matter how much time and money is devoted to such an effort. The system's reliability and resilience can be improved but never made perfect. Thus, system owners, operators, and regulators must prioritize their investments based on potential benefits. Enhancing the Resilience of the Nation's Electricity System focuses on identifying, developing, and implementing strategies to increase the power system's resilience in the face of events that can cause large-area, long-duration outages: blackouts that extend over multiple service areas and last several days or longer. Resilience is not just about lessening the likelihood that these outages will occur. It is also about limiting the scope and impact of outages when they do occur, restoring power rapidly afterwards, and learning from these experiences to better deal with events in the future.

Download or read book Distributed Energy Resources in Microgrids written by Rajeev Kumar Chauhan and published by Academic Press. This book was released on 2019-08-17 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt: Distributed Energy Resources in Microgrids: Integration, Challenges and Optimization unifies classically unconnected aspects of microgrids by considering them alongside economic analysis and stability testing. In addition, the book presents well-founded mathematical analyses on how to technically and economically optimize microgrids via distributed energy resource integration. Researchers and engineers in the power and energy sector will find this information useful for combined scientific and economical approaches to microgrid integration. Specific sections cover microgrid performance, including key technical elements, such as control design, stability analysis, power quality, reliability and resiliency in microgrid operation. Addresses the challenges related to the integration of renewable energy resources Includes examples of control algorithms adopted during integration Presents detailed methods of optimization to enhance successful integration

Download or read book Island Power Systems written by Lukas Sigrist and published by CRC Press. This book was released on 2016-12-01 with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt: A major concern of island power systems is frequency stability. A power system is said to be frequency stable if its generators are able to supply their loads at a frequency within acceptable limits after a disturbance. Frequency instability occurs if load-generation imbalances are not corrected in appropriate manner and time. Since island power systems are more sensitive to frequency instability than large ones due to the smaller number of generators online and the lower inertia, they require a larger amount of primary reserve per generator. This book provides a worldwide overview of island power systems, describing their main features and issues. Split into two parts, the first part examines the technical operation, and in particular, frequency stability of island power systems and its technical solutions, including more efficient underfrequency load-shedding schemes. The chapters explore both conventional and advanced load-shedding schemes and consider the improvement of these schemes by making them more robust and efficient. Advanced devices are modelled and analyzed to enhance frequency stability and reduce the need for load shedding. In the second part, the economic operation of island power systems is explored in detail. For that purpose, regulations and economic operations (centralized vs. market scheme) are reviewed by the authors. The authors discuss models for renewable energy sources and for advanced devices and systems such as demand-side management, energy storage systems, and electric vehicles. This book will be critical reading to all researchers and professionals in power system planning and engineering, electrical/power delivery, RES and control engineering. It will also be of interest to researchers in signal processing and telecommunications and renewable energy, as well as power system utility providers.

Download or read book Planning Optimal Load Distribution and Maximum Renewable Energy from Wind Power on a Radial Distribution System written by Handuwala Dewage Dulan Jayanatha Weerasinghe and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimizing renewable distributed generation in distribution systems has gained popularity with changes in federal energy policies. Various studies have been reported in this regard and most of the studies are based on optimum wind and/or solar generation planning in distribution system using various optimization techniques such as analytical, numerical, and heuristic. However, characteristics such as high energy density, relatively lower footprint of land, availability, and local reactive power compensation ability, have gained increased popularity for optimizing distributed wind generation (DWG) in distribution systems. This research investigated optimum distributed generation planning (ODGP) using two primary optimization techniques: analytical and heuristic. In first part of the research, an analytical optimization method called "Combined Electrical Topology (CET)" was proposed in order to minimize the impact of intentional structural changes in distribution system topology, in distributed generation/ DWG placement. Even though it is still rare, DWG could be maximized to supply base power demand of three-phase unbalanced radial distribution system, combined with distributed battery energy storage systems (BESS). In second part of this research the usage of DWG/BESS as base power generation, and to extend the ability to sustain the system in a power grid failure for a maximum of 1.5 hours was studied. IEEE 37-node, three-phase unbalanced radial distribution system was used as the test system to optimize wind turbines and sodium sulfide (NaS) battery units with respect to network real power losses, system voltage profile, DWG/BESS availability and present value of cost savings. In addition, DWG ability to supply local reactive power in distribution system was also investigated. Model results suggested that DWG/NaS could supply base power demand of a threephase unbalanced radial distribution system. In addition, DWG/NaS were able to sustain power demand of a three-phase unbalanced distribution system for 1.5 hours in the event of a power grid failure.

Download or read book Smart Grid Operational Strategies for Power Distribution Systems with Large Penetration of Distributed Energy Resources written by Ahmadreza Malekpour and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Power distribution systems are transitioning from traditional centralized-control distribution grids to the modern distribution grids that are more customer-interactive and include microgrids (MGs) as well as various unpredictable and multi-scale distributed energy resources (DERs). However, power fueled by renewable DERs such as wind and solar is highly variable and high penetration of renewable DERs in distribution system may potentially degrade the grid reliability and power quality. Moreover, the growth of such generation sources will increase the number of variables and cause scalability concerns for distribution system operators (DSOs) in handling system optimization problems. Further, with development of MGs, DSO and MG may have different owners and schedule renewable and non-renewable DERs based on their own economic rules and policies while secure and economic operation of the entire system is necessary. The widespread integration of wind and solar and deployment of MGs in distribution system make the task of distribution system operation management quite challenging especially from the viewpoint of variability, scalability, and multi-authority operation management. This research develops unique models and methodologies to overcome such issues and make distribution grid operation, optimization and control more robust against renewable intermittency, intractability, and operation complexity. The objectives of this research are as follows: 1) to develop a three-phase unbalanced large-scale distribution system to serve as a benchmark for studying challenges related to integration of DERs, such as scalability concerns in optimization problems, incremental power losses, voltage rise, voltage fluctuations, volt/var control, and operation management; 2) to develop a novel hierarchical and multilevel distributed optimization for power loss minimization via optimal reactive power provisioning from rooftop PVs which addresses the scalability issues with widespread DER integration in large-scale networks; 3) to develop a dynamic operational scheme for residential PV smart inverters to mitigate the fluctuations from rooftop PV integration under all-weather-condition (fully sunny, overcast and transient cloudy days) while increasing network efficiency in terms of power losses, and number of transformer load tap changer (LTC) operation; 4) to develop a stochastic energy management model for multi-authority distribution system operating under uncertainty from load and wind generation, which is able to precisely account interactions between DSO and MGs.

Download or read book Integration of Renewable Energy Sources Into the Power Grid Through PowerFactory written by Morteza Zare Oskouei and published by Springer Nature. This book was released on 2020-05-19 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book evaluates a number of serious technical challenges related to the integration of renewable energy sources into the power grid using the DIgSILENT PowerFactory power system simulation software package. It provides a fresh perspective on analyzing power systems according to renewable energy sources and how they affect power system performance in various situations. The book examines load flow, short-circuit, RMS simulation, power quality, and system reliability in the presence of renewable energy sources, and presents readers with the tools needed for modeling, simulation, and analysis for network planning. The book is a valuable resource for researchers, engineers, and students working to solve power system problems in the presence of renewable energy sources in power system operations and utilities.